There were several hours of CI attempts in NW TX/SW OK, yet only two of these managed to become just short-lived SVR-warned storms. Meanwhile, in KS, the few CI attempts developed into several long-lived supercells which went on to produce several tornadoes. Forecasting CI is difficult

Surface confluence is maybe only marginally stronger today, but already starting to see cumulus start to develop along the dryline in C OK and behind it in TX. I would not be surprised to see dryline CI by early evening, and for these storms to be stronger (and more severe) than yesterday (2/2)

Today's dryline (mesonet) is sharper than yesterday's (4/12; HRRRR 00z analysis). While yesterday's dryline did initiate storms in TX panhandle, they were mostly sub-severe in <60F dewpoints. Dryline CI today will more quickly be able to traverse from the dryline into rich >60F dewpoints (1/2)

With limited synoptic support, it's hard to see this dryline alone being able to initiate a sustained storm that can take advantage of the richer moisture in C KS/W OK. However, all it will take is a subtle mesoscale wave not captured in the CAMs or a synergistic terrain effect to change that (2/2)

Currently, there's far more cumulus development occurring behind the dryline than ahead of it. Still plenty of time for heating and mixing to sharpen the boundary, but SW winds on both sides of the dryline will limit the degree of along-dryline convergence (1/2)

Does the atmosphere care? No. There will be far more impressive drylines this spring that fail to initiate a single storm. All of the other atmospheric factors aligned yesterday so that this marginal feature was able to give just enough kick to be a focus point for initiation. (3/3)

It's reasonable to debate whether this should qualify as a dryline (WPC does not label it as such).
Is there a dewpoint gradient with some mixing processes we typically associate with drylines present? Yes.
Does the boundary meet our subjective criteria to define it as a dryline? Debatable. (2/3)

Yesterday's (4/9) "dryline" was one of the weakest I've seen: a diffuse dewpoint gradient of ~5-10F with surface dewpoint on the "moist" side in the mid-40s F and a minimal wind shift across the boundary. And yet, we saw widespread convection initiation along it from W TX through KS. (1/3)

While the increase in synoptic influences (not to mention cloud cover differences) make it unwise to simply apply today's biases to Tues/Wed, today's evolution may at least tell us something about how well CAMs depict the diurnal mixing element of dryline evolution in the current environment. (5/5)

...due to diurnal mixing. With dry soil moisture anomalies across the southern Great Plains, we can expect these processes might occur "faster" due to weaker surface moisture and increased ground sensible heating/mixing. How well will CAMs model the diurnal evolution? (4/5)

Dryline evolution across each day will be distinct as synoptic-scale forcing becomes a larger and larger influence. But something I'll have my eye on today will be how far east the dryline progresses compared to currently modeled. With (mostly) clear skies, progression should be primarily... (3/5)

Mon: weakly-forced dryline with a weak low (1002mb) in central KS.
Tues: still weakly-forced, but more compact 1002mb low in TX panhandle with a cold front pushing down from the north.
Wed: substantial synoptic forcing from a 994mb lee cyclone in southeast CO associated with upper-level trough (2/5)

3 days, 3 (currently) marginal severe storm outlooks from the SPC in the southern great plains all related to the dryline, each with its own unique flavor. (1/5)

...the confluence band moving north from the sharper dryline gradient in N TX. As this band nears I-35 at/north of OKC, we could see more robust CI. This is a fascinating example of the dryline as less of a "line" and more as a broad zone. (2/2)

2200z: The many CI attempts along I-44 have struggled, while those closer to I-35 are far more numerous and organized. While the dryline is technically in W OK, there's a broad zone of decreasing Td as far east of I-35, likely contributing to the struggles of sustaining CI along... (1/2)

...on CI in C OK/N TX and the early evolution of convection and its hazards. (5/5)

Notably, this distinct secondary Td gradient in OK is not developed yet in the current obs (although the current Td gradient from C to W OK is consistent with latest modeled evolution). When and where these localized enhanced confluence zones set up will likely have a significant influence... (4/5)

...with the lee cyclone? Either way, as modeled, this zone in C OK and the tightest Td gradient in N TX appear to have the strongest surface confluence. I would expect these zones to be the most likely areas for successful CI, with other dryline-CI attempts struggling with weaker forcing. (3/n)

Latest HRRR depicts 00z dryline across W OK. But, somewhat similar to yesterday, there is a notable secondary ~10F Td gradient in C OK ahead of the dryline. Maybe this is due to differential heating related to current cloud cover lingering in C OK? Or confluence band associated... (2/n)

More #okwx #txwx dryline yapping from me: Latest HRRR runs have reduced the CIN in central OK, possibly in response to assimilating 18z Norman sounding showcasing just a smidge of a warm nose remaining. As such, latest runs have also begun depicting dryline-vicinity CI ~22z in N TX. (1/n)

...of synoptic-scale and dryline lifting.

3) The other wild card here is the evolution of the lee cyclone. Any change in propagation speed or intensity relative to modeled will have a ripple effect on these smaller-scale factors directly influencing CI.

Another difficult CI forecasting day. (9/9)

...may not have as substantial as a role as it did yesterday.

2) How does the leading upper-level vorticity maxima evolve? Faster eastward propagation can make dryline CI more likely as upper-level descent more quickly moves east of C OK. Slower propagation may allow for a positive phasing... (8/9)

In "synoptically-active" dryline cases such as this, there are far more knobs to turn to make dryline CI less/more likely. A few things to watch for:
1: How does current cloud cover evolve and influence dryline propagation relative to modeled? Given the other synoptic forces at play, this... (7/9)

This is starting to get out of my depth, but a weak vorticity maxima appears to cross C/E OK ~18z. This may serve as the forcing for E OK convection seen in the HRRR, but in the wake of that, descent would be expected across C OK, which may be somewhat suppressing dryline lifting processes. (6/9)

(it's not just the HRRR either. Other CAMs also only depict convection well east of the dryline) (5/9)

Forecast sounding from Norman at this time shows a decently stout capping inversion still present as the likely culprit, with notable CIN present across much of central OK and N TX. (4/9)

The HRRR depicts a sharp dryline extending south from a lee cyclone in NW OK. Yet, aside from a couple of storms in N TX, the HRRR isn't depicting much CI along this dryline, which seems odd at first glance. (3/9)

Currently, the dryline is in the central TX panhandle, with a cold front trailing behind it and intersecting it in the north. While central OK is currently under heavy cloud cover and some precip, this is quickly moving east, setting up the potential for a lot of sun ahead of the dryline. (2/9)

3/6/26: Another potentially big severe day with a lot of moving pieces. Similar to yesterday, I'm going to take a dive into just the dryline forecast and see what it might mean for dryline CI in C OK and N TX (1/9) #okwx #txwx

The dryline is well west of the action, so how CI evolves over the next few hours is outside my knowledge realm. On a side note, it's pretty cool to see the difference in color between the west and east side of the dryline, with the east (less well-mixed) side appearing murkier! (3/3)