3/20/2007 FCST: KS/OK/TX

[Verne Carlson]

Time to start a forecast thread for this first day of possibly three days in a row for chasing in the TX/OK panhandles and east into central OK.

GFS continues to want to bring a neutral axis trough into the TX/OK panhandle at 0Z with 45Kt winds nosing into mid 50s Tds in sw KS/OK panhandles. Precip breaks out by 0Z in this area of the triple point with a distinct dryline down along the TX/OK border. Surface winds back along the KS/OK border near Liberal, KS. This could be the 'day before' event if the 500mb winds continue to progress on each GFS run.

 

[BrandonWhittington]

Ok, no one is really talking about Prospects on Tues. TDs should make it into the upper 50s and lower 60s on Tuesday. With the stalled front being somewhere in this neck of the woods, Storms should fire at peak heating. I really feel that the cap will hold off storm ignition until peak heating, but at that time, storms will break through the cap. One thing I like about Tuesday is the fact that we will not have to worry about mornign convection. Heating will be great all day. Also, it does appear that the dryline will start to develop during the day on Tuesday. TDs here in the panhandles range from the mid 50s east, to the 20s west. CAPE values appear to be around 1500/. Depending on how strong the cap is, the storms that do manage to break it, should be explosive.... Happy Chasing.

 

[Amos Magliocco]

Agree with Brandon that Tuesday is a potential sleeper. Midlevel winds are anemic but models have advertised a shortwave crossing the moisture axis for days now, giving a little boost to the shear and tightening the dryline. SR anvil level flow is well below what I'd normally monitor but with the warm front in the neighborhood any rotating storm traversing the boundary could take advantage of the low level shear and modest instabilities. Though its greatly flawed I feel like Tuesday is disproportionately less complicated than Wednesday and especially Thursday through Saturday, with the model divergence after 3/21 and potential for heavy rainfall in the warm sector.

 

[Ilya Neyman]

I agree, I've been keeping a close eye on the prospects for Tuesday for several days now and depending on how things unfold it may be the popularly used "day before the day" event. There are several things that point toward the potential for an interesting scenario, and others that are rather up in the air.

Progs have been consistent in forecasting a stationary front draped across the vicinity of northern OK during the morning, lifting northward as a warm front during the afternoon. In addition, storms are a pretty good bet around this feature per model agreement, but these may be elevated, at least initially. There is rather good low-level shear forecasted, however, the upper-level winds are quite weak, only on the order of 30 knots or so at 300mb.

Farther south jet-stream energy is much better with the nose of a 60-70 knot southern stream jet punching into west TX by 00z Wed. That coupled with ample dewpoints approaching or even exceeding 60, as well as strengthening 850 flow and temperatures in the 70s and 80s, especially in the vicinity of the caprock may be enough to fire some activity by late afternoon. Something that would definitely further the chances of this happening is some upper energy ejecting out of the mean trough in the form of a lead shortwave that the models had been indicating rather nicely the last several days, but the most recent runs are a bit more uncertain with regards to the details now. I'm watching the southern 2/3rds of the TX panhadle, especially from an Amarillo to Childress to Lubbock area for this possibility. This area would, in my opinion, favor isolated discrete supercell development. Of course, the big question is the cap strength, and I have not looked at the forecast soundings for this area yet, but I can picture a scenario where good warm/moist upslope flow combined with a subtle shortwave during peak heating may be enough to fire a storm or two off the caprock.

Definitely something to watch and nice to see it addressed!

~Ilya Neyman

 

[Ray Walker]

I think dewpoints will be well into the 60's by tuesday, I live in Ada Oklahoma and dewpoints are already in the low 60s here. Since Tuesday is still two days away with southerly flow continuing, well it should be interesting to say the least.