Space Weather Message Code: WARK05 Serial Number: 2225 Issue Time: 2026 Apr 18 2350 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2026 Apr 18 2348 UTC Valid To: 2026 Apr 19 0900 UTC Warning Condition: Onset NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale G2). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 3.33 5.00 (G1) 3.67 03-06UT 5.00 (G1) 4.67 (G1) 3.67 06-09UT 5.67 (G2) 4.00 3.33 09-12UT 5.00 (G1) 3.33 3.33 12-15UT 5.00 (G1) 3.67 3.33 15-18UT 4.33 3.00 2.00 18-21UT 4.00 3.00 3.33 21-00UT 6.00 (G2) 3.33 3.33 Rationale: G1-G2 (Minor-Moderate) geomagnetic storming levels are expected on 18 Apr as negative polarity CH HSS geomagnetic conditions persist. Active to G1 (Minor) levels are expected to continue through 19 Apr, followed by unsettled to active conditions on 20 Apr, as HSS effects linger. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: There is a chance for R1-R2 (Minor-Moderate) flares on 18-20 Apr, primarily due to the flare potential of Region 4419.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-19T00:00:03Z

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Apr 18 2348 UTC
Valid To: 2026 Apr 19 0900 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5319 Issue Time: 2026 Apr 18 2246 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5318 Valid From: 2026 Apr 18 0157 UTC Now Valid Until: 2026 Apr 19 1200 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 6 (NOAA Scale G2). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 3.33 5.00 (G1) 3.67 03-06UT 5.00 (G1) 4.67 (G1) 3.67 06-09UT 5.67 (G2) 4.00 3.33 09-12UT 5.00 (G1) 3.33 3.33 12-15UT 5.00 (G1) 3.67 3.33 15-18UT 4.33 3.00 2.00 18-21UT 4.00 3.00 3.33 21-00UT 6.00 (G2) 3.33 3.33 Rationale: G1-G2 (Minor-Moderate) geomagnetic storming levels are expected on 18 Apr as negative polarity CH HSS geomagnetic conditions persist. Active to G1 (Minor) levels are expected to continue through 19 Apr, followed by unsettled to active conditions on 20 Apr, as HSS effects linger. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: There is a chance for R1-R2 (Minor-Moderate) flares on 18-20 Apr, primarily due to the flare potential of Region 4419.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T22:50:03Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5318
Valid From: 2026 Apr 18 0157 UTC
Now Valid Until: 2026 Apr 19 1200 UTC
Warning Condition: Persistence
Additional Details Here.

Space Weather Message Code: ALTK05 Serial Number: 2009 Issue Time: 2026 Apr 18 1124 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Apr 18 1124 UTC Synoptic Period: 0900-1200 UTC Active Warning: Yes NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T11:30:03Z

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 18 1124 UTC
Synoptic Period: 0900-1200 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: ALTK06 Serial Number: 713 Issue Time: 2026 Apr 18 0825 UTC ALERT: Geomagnetic K-index of 6 Threshold Reached: 2026 Apr 18 0825 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes NOAA Scale: G2 - Moderate NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 55 degrees Geomagnetic Latitude. Induced Currents - Power grid fluctuations can occur. High-latitude power systems may experience voltage alarms. Spacecraft - Satellite orientation irregularities may occur; increased drag on low Earth-orbit satellites is possible. Radio - HF (high frequency) radio propagation can fade at higher latitudes. Aurora - Aurora may be seen as low as New York to Wisconsin to Washington state.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T08:30:03Z

ALERT: Geomagnetic K-index of 6
Threshold Reached: 2026 Apr 18 0825 UTC
Synoptic Period: 0600-0900 UTC

Active Warning: Yes
NOAA Scale: G2 - Moderate
Additional Details Here.

Space Weather Message Code: ALTK05 Serial Number: 2008 Issue Time: 2026 Apr 18 0741 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Apr 18 0740 UTC Synoptic Period: 0600-0900 UTC Active Warning: Yes NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T07:50:03Z

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 18 0740 UTC
Synoptic Period: 0600-0900 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: ALTK05 Serial Number: 2007 Issue Time: 2026 Apr 18 0528 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Apr 18 0525 UTC Synoptic Period: 0300-0600 UTC Active Warning: Yes NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T05:30:03Z

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 18 0525 UTC
Synoptic Period: 0300-0600 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: ALTK04 Serial Number: 2650 Issue Time: 2026 Apr 18 0414 UTC ALERT: Geomagnetic K-index of 4 Threshold Reached: 2026 Apr 18 0414 UTC Synoptic Period: 0300-0600 UTC Active Warning: Yes NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T04:20:03Z

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Apr 18 0414 UTC
Synoptic Period: 0300-0600 UTC

Active Warning: Yes
Additional Details Here.

Space Weather Message Code: WARK05 Serial Number: 2224 Issue Time: 2026 Apr 18 0317 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2026 Apr 18 0317 UTC Valid To: 2026 Apr 18 1800 UTC Warning Condition: Onset NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T03:20:03Z

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Apr 18 0317 UTC
Valid To: 2026 Apr 18 1800 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5318 Issue Time: 2026 Apr 18 0158 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2026 Apr 18 0157 UTC Valid To: 2026 Apr 18 2359 UTC Warning Condition: Onset NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 18 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 18-Apr 20 2026 is 6.00 (NOAA Scale G2). NOAA Kp index breakdown Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 00-03UT 6.00 (G2) 5.00 (G1) 3.67 03-06UT 6.00 (G2) 4.67 (G1) 3.67 06-09UT 5.00 (G1) 4.00 3.33 09-12UT 4.00 3.33 3.33 12-15UT 3.67 3.67 3.33 15-18UT 3.33 3.00 2.00 18-21UT 3.00 3.00 3.33 21-00UT 4.33 3.33 3.33 Rationale: G1 (Minor) to G2 (Moderate) geomagnetic storming is likely on 18 Apr, with G1 (Minor) storming likely continuing on into the early portions of 19 Apr, due to negative polarity coronal hole high speed stream influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 18-Apr 20 2026 Apr 18 Apr 19 Apr 20 R1-R2 25% 25% 25% R3 or greater 5% 5% 5% Rationale: R1-2 (Minor-Moderate) radio blackouts due to isolated M-class flare activity are likely through 28 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-18T02:00:03Z

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 18 0157 UTC
Valid To: 2026 Apr 18 2359 UTC
Warning Condition: Onset
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5317 Issue Time: 2026 Apr 12 0945 UTC CANCEL WARNING: Geomagnetic K-index of 4 expected Cancel Serial Number: 5316 Original Issue Time: 2026 Apr 10 0143 UTC Comment: Active conditions (Kp=4) are no longer expected to occur. NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 12 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 12-Apr 14 2026 is 4.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 12-Apr 14 2026 Apr 12 Apr 13 Apr 14 00-03UT 2.67 2.67 2.00 03-06UT 3.67 3.00 2.00 06-09UT 3.67 2.67 1.00 09-12UT 2.67 1.67 2.00 12-15UT 2.00 1.67 1.67 15-18UT 1.67 1.00 3.00 18-21UT 1.67 1.00 3.67 21-00UT 2.67 2.00 4.00 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 12-Apr 14 2026 Apr 12 Apr 13 Apr 14 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 12-Apr 14 2026 Apr 12 Apr 13 Apr 14 R1-R2 10% 10% 10% R3 or greater 1% 1% 1% Rationale: A slight chance for R1 (Minor) or greater radio blackouts are expected on 12-14 Apr,

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-12T09:50:03Z

CANCEL WARNING: Geomagnetic K-index of 4 expected
Cancel Serial Number: 5316
Original Issue Time: 2026 Apr 10 0143 UTC
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5316 Issue Time: 2026 Apr 11 1756 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5315 Valid From: 2026 Apr 10 0145 UTC Now Valid Until: 2026 Apr 12 1500 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 11 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 11-Apr 13 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Apr 11-Apr 13 2026 Apr 11 Apr 12 Apr 13 00-03UT 2.00 2.67 2.67 03-06UT 4.00 3.67 3.00 06-09UT 3.33 3.67 2.67 09-12UT 3.33 2.67 1.67 12-15UT 3.00 2.00 1.67 15-18UT 2.67 1.67 1.67 18-21UT 3.67 1.67 2.00 21-00UT 4.67 (G1) 2.67 2.67 Rationale: G1 (Minor) geomagnetic storming is likely on 11 Apr due to +CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 11-Apr 13 2026 Apr 11 Apr 12 Apr 13 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 11-Apr 13 2026 Apr 11 Apr 12 Apr 13 R1-R2 5% 5% 5% R3 or greater 1% 1% 1% Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-11T18:00:03Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5315
Valid From: 2026 Apr 10 0145 UTC
Now Valid Until: 2026 Apr 12 1500 UTC
Warning Condition: Persistence
Additional Details Here.

Space Weather Message Code: WARK05 Serial Number: 2223 Issue Time: 2026 Apr 10 1426 UTC WARNING: Geomagnetic K-index of 5 expected Valid From: 2026 Apr 10 1425 UTC Valid To: 2026 Apr 11 0900 UTC Warning Condition: Onset NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 10 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 10-Apr 12 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 00-03UT 4.00 3.67 3.67 03-06UT 2.67 4.67 (G1) 3.67 06-09UT 2.67 4.00 3.67 09-12UT 2.00 3.67 2.67 12-15UT 3.67 2.67 2.67 15-18UT 2.67 2.67 1.67 18-21UT 4.00 4.00 2.67 21-00UT 4.67 (G1) 4.67 (G1) 3.00 Rationale: Periods of G1 (Minor) geomagnetic storming are likely on 10-11 Apr due to +CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 R1-R2 5% 5% 5% R3 or greater 1% 1% 1% Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-10T14:30:03Z

WARNING: Geomagnetic K-index of 5 expected
Valid From: 2026 Apr 10 1425 UTC
Valid To: 2026 Apr 11 0900 UTC
Warning Condition: Onset
NOAA Scale: G1 - Minor
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5315 Issue Time: 2026 Apr 10 1350 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5314 Valid From: 2026 Apr 10 0145 UTC Now Valid Until: 2026 Apr 11 1800 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 10 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 10-Apr 12 2026 is 4.67 (NOAA Scale G1). NOAA Kp index breakdown Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 00-03UT 4.00 3.67 3.67 03-06UT 2.67 4.67 (G1) 3.67 06-09UT 2.67 4.00 3.67 09-12UT 2.00 3.67 2.67 12-15UT 3.67 2.67 2.67 15-18UT 2.67 2.67 1.67 18-21UT 4.00 4.00 2.67 21-00UT 4.67 (G1) 4.67 (G1) 3.00 Rationale: Periods of G1 (Minor) geomagnetic storming are likely on 10-11 Apr due to +CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 S1 or greater 1% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 R1-R2 5% 5% 5% R3 or greater 1% 1% 1% Rationale: No R1 (Minor) or greater radio blackouts are expected. No significant active region flare activity is forecast.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-10T14:00:03Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5314
Valid From: 2026 Apr 10 0145 UTC
Now Valid Until: 2026 Apr 11 1800 UTC
Warning Condition: Persistence
Additional Details Here.

Space Weather Message Code: ALTK04 Serial Number: 2649 Issue Time: 2026 Apr 10 0208 UTC ALERT: Geomagnetic K-index of 4 Threshold Reached: 2026 Apr 10 0205 UTC Synoptic Period: 0000-0300 UTC Active Warning: Yes NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 10 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 10-Apr 12 2026 is 5.33 (NOAA Scale G1). NOAA Kp index breakdown Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 00-03UT 3.33 5.33 (G1) 4.33 03-06UT 5.00 (G1) 4.00 3.67 06-09UT 4.33 4.00 2.67 09-12UT 3.67 3.33 2.33 12-15UT 2.67 3.67 3.00 15-18UT 2.67 4.00 2.33 18-21UT 2.67 4.67 (G1) 3.00 21-00UT 4.33 4.67 (G1) 3.33 Rationale: G1 (Minor) storm levels are likely over 10-11 Apr due to the influence of a +CH HSS. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 S1 or greater 5% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 09 2026 0845 UTC. Radio Blackout Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 R1-R2 25% 5% 5% R3 or greater 1% 1% 1% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts on 10 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-10T02:10:03Z

ALERT: Geomagnetic K-index of 4
Threshold Reached: 2026 Apr 10 0205 UTC
Synoptic Period: 0000-0300 UTC

Active Warning: Yes
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5314 Issue Time: 2026 Apr 10 0143 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2026 Apr 10 0145 UTC Valid To: 2026 Apr 10 1500 UTC Warning Condition: Onset NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 10 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 10-Apr 12 2026 is 5.33 (NOAA Scale G1). NOAA Kp index breakdown Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 00-03UT 3.33 5.33 (G1) 4.33 03-06UT 5.00 (G1) 4.00 3.67 06-09UT 4.33 4.00 2.67 09-12UT 3.67 3.33 2.33 12-15UT 2.67 3.67 3.00 15-18UT 2.67 4.00 2.33 18-21UT 2.67 4.67 (G1) 3.00 21-00UT 4.33 4.67 (G1) 3.33 Rationale: G1 (Minor) storm levels are likely over 10-11 Apr due to the influence of a +CH HSS. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 S1 or greater 5% 1% 1% Rationale: No S1 (Minor) or greater solar radiation storms are expected. No significant active region activity favorable for radiation storm production is forecast. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 09 2026 0845 UTC. Radio Blackout Forecast for Apr 10-Apr 12 2026 Apr 10 Apr 11 Apr 12 R1-R2 25% 5% 5% R3 or greater 1% 1% 1% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts on 10 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-10T01:50:03Z

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 10 0145 UTC
Valid To: 2026 Apr 10 1500 UTC
Warning Condition: Onset
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5313 Issue Time: 2026 Apr 07 0124 UTC WARNING: Geomagnetic K-index of 4 expected Valid From: 2026 Apr 07 0124 UTC Valid To: 2026 Apr 07 1200 UTC Warning Condition: Onset NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 07 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 3 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 07-Apr 09 2026 is 2.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 07-Apr 09 2026 Apr 07 Apr 08 Apr 09 00-03UT 2.67 1.67 1.67 03-06UT 2.67 1.67 1.67 06-09UT 2.67 1.67 1.67 09-12UT 2.67 1.33 1.00 12-15UT 2.33 0.67 0.67 15-18UT 2.33 0.67 1.33 18-21UT 1.67 1.67 1.33 21-00UT 1.33 2.00 1.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 07-Apr 09 2026 Apr 07 Apr 08 Apr 09 S1 or greater 10% 10% 10% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 07-09 Apr. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 07-Apr 09 2026 Apr 07 Apr 08 Apr 09 R1-R2 40% 40% 40% R3 or greater 10% 10% 10% Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts, with a slight chance for R3 (Strong) or greater events, on 07-09 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-07T01:30:02Z

WARNING: Geomagnetic K-index of 4 expected
Valid From: 2026 Apr 07 0124 UTC
Valid To: 2026 Apr 07 1200 UTC
Warning Condition: Onset
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5312 Issue Time: 2026 Apr 05 0248 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5311 Valid From: 2026 Apr 02 0047 UTC Now Valid Until: 2026 Apr 05 0900 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 06 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 06-Apr 08 2026 is 3.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 00-03UT 2.67 2.67 1.67 03-06UT 3.00 2.67 1.67 06-09UT 2.67 2.67 1.67 09-12UT 2.67 2.00 1.33 12-15UT 2.00 0.67 0.67 15-18UT 1.67 0.67 0.67 18-21UT 1.67 1.67 1.67 21-00UT 2.67 2.67 2.00 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 S1 or greater 15% 15% 15% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 06-08 Apr. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 R1-R2 55% 55% 55% R3 or greater 15% 15% 15% Rationale: R1 (Minor) radio blackout levels are likely, with a slight chance for an isolated R3 (Strong) event over 06-08 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-06T11:09:56Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5311
Valid From: 2026 Apr 02 0047 UTC
Now Valid Until: 2026 Apr 05 0900 UTC
Warning Condition: Persistence
Additional Details Here.

I am aware of the issues with the "missing data" images in posts recently. NOAA's site where those come from has not been populating the forecast images. I'm working on alternate feeds.

Sorry for the troubles.

:Product: 3-Day Forecast :Issued: 2026 Apr 06 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 06-Apr 08 2026 is 3.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 00-03UT 2.67 2.67 1.67 03-06UT 3.00 2.67 1.67 06-09UT 2.67 2.67 1.67 09-12UT 2.67 2.00 1.33 12-15UT 2.00 0.67 0.67 15-18UT 1.67 0.67 0.67 18-21UT 1.67 1.67 1.67 21-00UT 2.67 2.67 2.00 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 S1 or greater 15% 15% 15% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 06-08 Apr. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 R1-R2 55% 55% 55% R3 or greater 15% 15% 15% Rationale: R1 (Minor) radio blackout levels are likely, with a slight chance for an isolated R3 (Strong) event over 06-08 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-06T07:04:01Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 06 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 06-Apr 08 2026 is 3.00 (below NOAA Scale levels). NOAA Kp index breakdown Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 00-03UT 2.67 2.67 1.67 03-06UT 3.00 2.67 1.67 06-09UT 2.67 2.67 1.67 09-12UT 2.67 2.00 1.33 12-15UT 2.00 0.67 0.67 15-18UT 1.67 0.67 0.67 18-21UT 1.67 1.67 1.67 21-00UT 2.67 2.67 2.00 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 S1 or greater 15% 15% 15% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 06-08 Apr. C. NOAA Radio Blackout Activity and Forecast No radio blackouts were observed over the past 24 hours. Radio Blackout Forecast for Apr 06-Apr 08 2026 Apr 06 Apr 07 Apr 08 R1-R2 55% 55% 55% R3 or greater 15% 15% 15% Rationale: R1 (Minor) radio blackout levels are likely, with a slight chance for an isolated R3 (Strong) event over 06-08 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-06T01:04:02Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 05 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 05-Apr 07 2026 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 00-03UT 3.67 2.67 2.67 03-06UT 3.00 3.00 2.67 06-09UT 3.00 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 2.00 2.00 0.67 15-18UT 1.67 1.67 0.67 18-21UT 1.67 1.67 1.67 21-00UT 2.00 2.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 05-07 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 04 2026 2304 UTC. Radio Blackout Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for X-class R3 (Strong) events, over 05-07 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T19:04:01Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 05 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA Scale levels). The greatest expected 3 hr Kp for Apr 05-Apr 07 2026 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 00-03UT 3.67 2.67 2.67 03-06UT 3.00 3.00 2.67 06-09UT 3.00 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 2.00 2.00 0.67 15-18UT 1.67 1.67 0.67 18-21UT 1.67 1.67 1.67 21-00UT 2.00 2.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 05-07 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 04 2026 2304 UTC. Radio Blackout Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for X-class R3 (Strong) events, over 05-07 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T13:04:01Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 05 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 5 (NOAA Scale G1). The greatest expected 3 hr Kp for Apr 05-Apr 07 2026 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 00-03UT 3.67 2.67 2.67 03-06UT 3.33 3.00 2.67 06-09UT 3.00 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 2.67 2.00 0.67 15-18UT 2.00 1.67 0.67 18-21UT 2.00 1.67 1.67 21-00UT 2.67 2.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 05-07 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an isolated R3 (Strong) event, over 05-07 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T07:04:01Z
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5312 Issue Time: 2026 Apr 05 0248 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5311 Valid From: 2026 Apr 02 0047 UTC Now Valid Until: 2026 Apr 05 0900 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 05 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 5 (NOAA Scale G1). The greatest expected 3 hr Kp for Apr 05-Apr 07 2026 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 00-03UT 3.67 2.67 2.67 03-06UT 3.33 3.00 2.67 06-09UT 3.00 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 2.67 2.00 0.67 15-18UT 2.00 1.67 0.67 18-21UT 2.00 1.67 1.67 21-00UT 2.67 2.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 05-07 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an isolated R3 (Strong) event, over 05-07 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T02:50:03Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5311
Valid From: 2026 Apr 02 0047 UTC
Now Valid Until: 2026 Apr 05 0900 UTC
Warning Condition: Persistence
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 05 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 5 (NOAA Scale G1). The greatest expected 3 hr Kp for Apr 05-Apr 07 2026 is 3.67 (below NOAA Scale levels). NOAA Kp index breakdown Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 00-03UT 3.67 2.67 2.67 03-06UT 3.33 3.00 2.67 06-09UT 3.00 2.67 2.67 09-12UT 3.00 2.67 2.00 12-15UT 2.67 2.00 0.67 15-18UT 2.00 1.67 0.67 18-21UT 2.00 1.67 1.67 21-00UT 2.67 2.67 2.67 Rationale: No G1 (Minor) or greater geomagnetic storms are expected. No significant transient or recurrent solar wind features are forecast. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 05-07 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 05-Apr 07 2026 Apr 05 Apr 06 Apr 07 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an isolated R3 (Strong) event, over 05-07 Apr, driven primarily by the flare potential of Region 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T01:04:01Z
Additional Details Here.

Space Weather Message Code: WARK04 Serial Number: 5311 Issue Time: 2026 Apr 04 2356 UTC EXTENDED WARNING: Geomagnetic K-index of 4 expected Extension to Serial Number: 5310 Valid From: 2026 Apr 02 0047 UTC Now Valid Until: 2026 Apr 05 0300 UTC Warning Condition: Persistence NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 65 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Aurora - Aurora may be visible at high latitudes such as Canada and Alaska.

:Product: 3-Day Forecast :Issued: 2026 Apr 04 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale G3). The greatest expected 3 hr Kp for Apr 04-Apr 06 2026 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 00-03UT 4.67 (G1) 3.67 2.67 03-06UT 3.67 3.67 3.00 06-09UT 2.67 3.67 2.67 09-12UT 2.67 2.67 2.67 12-15UT 4.67 (G1) 2.67 2.00 15-18UT 4.00 2.00 1.67 18-21UT 3.00 2.67 1.67 21-00UT 5.67 (G2) 2.67 2.67 Rationale: The geomagnetic field is expected to reach G1 (Minor) storm levels on 04 Apr, with periods of G2 (Moderate) storming likely, due to waning CME effects and negative polarity CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 04-06 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an R3 (Strong) or greater event, on 04-06 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-05T00:00:04Z

EXTENDED WARNING: Geomagnetic K-index of 4 expected
Extension to Serial Number: 5310
Valid From: 2026 Apr 02 0047 UTC
Now Valid Until: 2026 Apr 05 0300 UTC
Warning Condition: Persistence
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 04 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale G3). The greatest expected 3 hr Kp for Apr 04-Apr 06 2026 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 00-03UT 4.67 (G1) 3.67 2.67 03-06UT 3.67 3.67 3.00 06-09UT 2.67 3.67 2.67 09-12UT 2.67 2.67 2.67 12-15UT 4.67 (G1) 2.67 2.00 15-18UT 4.00 2.00 1.67 18-21UT 3.00 2.67 1.67 21-00UT 5.67 (G2) 2.67 2.67 Rationale: The geomagnetic field is expected to reach G1 (Minor) storm levels on 04 Apr, with periods of G2 (Moderate) storming likely, due to waning CME effects and negative polarity CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 04-06 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an R3 (Strong) or greater event, on 04-06 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-04T19:04:02Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 04 1230 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale G3). The greatest expected 3 hr Kp for Apr 04-Apr 06 2026 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 00-03UT 4.67 (G1) 3.67 2.67 03-06UT 3.67 3.67 3.00 06-09UT 2.67 3.67 2.67 09-12UT 2.67 2.67 2.67 12-15UT 4.67 (G1) 2.67 2.00 15-18UT 4.00 2.00 1.67 18-21UT 3.00 2.67 1.67 21-00UT 5.67 (G2) 2.67 2.67 Rationale: The geomagnetic field is expected to reach G1 (Minor) storm levels on 04 Apr, with periods of G2 (Moderate) storming likely, due to waning CME effects and negative polarity CH HSS influences. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 S1 or greater 20% 20% 20% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 04-06 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R2 levels were observed over the past 24 hours. The largest was at Apr 04 2026 0117 UTC. Radio Blackout Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 R1-R2 55% 55% 55% R3 or greater 20% 20% 20% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for an R3 (Strong) or greater event, on 04-06 Apr.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-04T13:04:01Z
Additional Details Here.

:Product: 3-Day Forecast :Issued: 2026 Apr 04 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale G3). The greatest expected 3 hr Kp for Apr 04-Apr 06 2026 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 00-03UT 5.00 (G1) 4.67 (G1) 2.67 03-06UT 5.67 (G2) 4.00 3.00 06-09UT 5.00 (G1) 3.67 3.67 09-12UT 4.00 3.00 2.67 12-15UT 4.67 (G1) 2.67 2.67 15-18UT 4.00 2.67 1.67 18-21UT 3.00 1.67 1.67 21-00UT 4.00 2.67 2.67 Rationale: G1-G2 (Minor-Moderate) storm levels are likely over 04 Apr due to combined effects of a CME that left the Sun on 01 Apr and influence from a negative polarity CH HSS. G1 (Minor) conditions are likely on 05 Apr as negative polarity CH HSS influences wane and any remnant CME enhancements subside. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 S1 or greater 15% 15% 15% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 04-06 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 03 2026 0756 UTC. Radio Blackout Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 R1-R2 55% 55% 55% R3 or greater 15% 15% 15% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for isolated R3 (Strong) events, over 04-06 Apr driven primarily by the flare potential of Regions 4404, 4405, and 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-04T07:04:01Z
Additional Details Here.

Space Weather Message Code: ALTK05 Serial Number: 2006 Issue Time: 2026 Apr 04 0254 UTC ALERT: Geomagnetic K-index of 5 Threshold Reached: 2026 Apr 04 0248 UTC Synoptic Period: 0000-0300 UTC Active Warning: Yes NOAA Scale: G1 - Minor NOAA Space Weather Scale descriptions can be found at www.swpc.noaa.gov/noaa-scales-explanation Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude. Induced Currents - Weak power grid fluctuations can occur. Spacecraft - Minor impact on satellite operations possible. Aurora - Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.

:Product: 3-Day Forecast :Issued: 2026 Apr 04 0030 UTC # Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center # A. NOAA Geomagnetic Activity Observation and Forecast The greatest observed 3 hr Kp over the past 24 hours was 7 (NOAA Scale G3). The greatest expected 3 hr Kp for Apr 04-Apr 06 2026 is 5.67 (NOAA Scale G2). NOAA Kp index breakdown Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 00-03UT 5.00 (G1) 4.67 (G1) 2.67 03-06UT 5.67 (G2) 4.00 3.00 06-09UT 5.00 (G1) 3.67 3.67 09-12UT 4.00 3.00 2.67 12-15UT 4.67 (G1) 2.67 2.67 15-18UT 4.00 2.67 1.67 18-21UT 3.00 1.67 1.67 21-00UT 4.00 2.67 2.67 Rationale: G1-G2 (Minor-Moderate) storm levels are likely over 04 Apr due to combined effects of a CME that left the Sun on 01 Apr and influence from a negative polarity CH HSS. G1 (Minor) conditions are likely on 05 Apr as negative polarity CH HSS influences wane and any remnant CME enhancements subside. B. NOAA Solar Radiation Activity Observation and Forecast Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was below S-scale storm level thresholds. Solar Radiation Storm Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 S1 or greater 15% 15% 15% Rationale: There is a slight chance for the greater than 10 MeV proton flux to exceed S1 (Minor) solar radiation storm levels over 04-06 Apr. C. NOAA Radio Blackout Activity and Forecast Radio blackouts reaching the R1 levels were observed over the past 24 hours. The largest was at Apr 03 2026 0756 UTC. Radio Blackout Forecast for Apr 04-Apr 06 2026 Apr 04 Apr 05 Apr 06 R1-R2 55% 55% 55% R3 or greater 15% 15% 15% Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a slight chance for isolated R3 (Strong) events, over 04-06 Apr driven primarily by the flare potential of Regions 4404, 4405, and 4409.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Map from NOAA titled showing North America and the North Pole with a color gradient overlay of aurora likelihood.

Aurora Forecast Update for 2026-04-04T03:00:03Z

ALERT: Geomagnetic K-index of 5
Threshold Reached: 2026 Apr 04 0248 UTC
Synoptic Period: 0000-0300 UTC

Active Warning: Yes
NOAA Scale: G1 - Minor
Additional Details Here.