40% of the continental US is now in severe, extreme, or exceptional drought... not good.

Verizon reminded me that today is my 23rd anniversary with them. I've had the same mobile number the entire time.

I've seen this come up a handful of times lately, so thought I'd nudge this back up. The "Main Development Region" (MDR) in the tropical Atlantic includes the Caribbean Sea. The MDR is comprised of the Caribbean Sea *and* the tropical east Atlantic.

By the way, the two related radar loops you'll find in the archive:
#Sinlaku 2008 (same name) and #Yutu 2018 (same landfall in Northern Marianas)
bmcnoldy.earth.miami.edu/tropics/radar/

Super Typhoon #Sinlaku has just crossed over the Northern Mariana Islands at Category 4 intensity, captured by the radar in Guam.

(This is the 619th radar loop in the archive... and the last time a Typhoon Sinlaku made an appearance was in 2008, from Taiwan)

bmcnoldy.earth.miami.edu/tropics/radar/

Sundogs at sunrise

From 2015:
www.facebook.com/share/1BkV6J...

Here are some stats on the extremes...
Earliest - July 2 (Beryl 2024)
Latest - November 8 (Unnamed 1932)
Southernmost - 13.4°N (Matthew 2016)
Northernmost - 30.3°N (Camille 1969)
Westernmost - 97.1°W (Anita 1977)
Easternmost - 45.0°W (Lorenzo 2019)
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This updated map shows just the portions of Atlantic hurricane tracks when they were at Category 5 intensity, including the incredible 2025 season which produced *3* Category 5 hurricanes. That brings the total number of Cat 5s in the database to 45.
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Donald Trump has done more damage to the United States of America than any foreign enemy accomplished in our nation’s 250-year history.

Yes... weekly values respond much quicker than a 3-month average, which is traditionally what is used for RONI (and ONI). So, with March being the latest complete month of data, the most recent RONI value is calculated from the Jan-Feb-Mar average.

And last year in the Atlantic, Imelda and Humberto were close enough to interact (but not merge): bsky.app/profile/bmcn...

Not a dumb question at all... tropical cyclone mergers can and do happen. And even if they don't completely merge, they can get close enough to interact and rotate around each other. Here's a paper I co-authored on the topic in 2003: doi.org/10.1175/1520...

Links:
bmcnoldy.earth.miami.edu/tropics/radar/
bmcnoldy.earth.miami.edu/tropics/atcf/

There are two nearly-identical storms centered just 1300 miles apart in the South Pacific. #Maila is near the Solomon Islands and #Vaianu is near Fiji.
I just started a radar loop for Vaianu from Nadi, Fiji. You can find that in the usual spot... this is the 618th radar loop in that archive.

The difference in the RONI values between using ERSST version 5 and 6 are minimal lately. The last couple of times the difference (barely) exceeded 0.1°C were Oct 2025 and Sep 2024. My plot shows the values calculated using version 6.

The difference in the RONI values between using ERSST version 5 and 6 are minimal lately. The last couple of times the difference (barely) exceeded 0.1°C were Oct 2025 and Sep 2024. My plot shows the values calculated using version 6.

The Relative Oceanic Niño Index (RONI) is up to -0.77°C... still a weak #LaNiña, but warming.
Forecasts over the coming months point to a very strong #ElNiño taking hold by summer and persisting into winter.
bmcnoldy.earth.miami.edu/tropics/roni/

(plus 25 donuts courtesy of very thoughtful friends)

Happy 25th anniversary, Tropical Cyclone Radar Loops archive! 🎉

Poster: bmcnoldy.earth.miami.edu/papers/McNol...

Nah, I don't do forecasting!

The mean temperature during March will be 61.2°F in #Albuquerque. How wild is that?
Well, the average for March is 49.5°, and for *April* it's 56.8°.
The previous all-time record-warmest March was 54.8°. We shot past that by an unimaginable 6.4°!!

Some of the early bloomers around the house...

One more new feature: The global archive page of TC-ATLAS now has a "models" toggle so you can review the evolution of past forecasts going back to 1991. Some notable examples of challenging forecasts below. michaelfischerwx.github.io/TC-ATLAS/ind...

Interested in hurricanes? I want to introduce TC-ATLAS: the Tropical Cyclone Analysis Tool for Live and Archived Structure. Explore live or past storms without writing a line of code or downloading a data file, building on the capabilities of TC-RADAR: michaelfischerwx.github.io/TC-ATLAS/ind...

My usual Friday dirty martini (gin-based).

Happy #MartiniFriday!

35th (New Orleans LA, 2022): "Non-expert comprehension of hurricane forecast graphs"
36th (Long Beach CA, 2024): "Dynamic communication of weather risk: A user-centered design approach"
37th (San Diego CA, 2026): "CYGNSS coverage statistics of tropical cyclones"
#AMS37Hurr
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33rd (Ponte Vedra Beach FL, 2018): "An evaluation of satellite-derived atmospheric motion vectors (AMV) characteristics in tropical cyclones using TCI HDSS dropsondes"
34th (Virtual, 2021): "The perceived value of improving hurricane forecast accuracy"
#AMS37Hurr
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31st (San Diego CA, 2014): "Further development and applications of an efficient and configurable vortex initialization technique"
32nd (San Juan PR, 2016): "Evaluation of the impact of CYGNSS wind speed data on tropical cyclone structure analyses and forecasts in a regional OSSE"
#AMS37Hurr
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