4/17/08 FCST: OK/TX

[Ilya Neyman]

I agree with the impressive features (namely winds) for the Wednesday afternoon-evening timeframe, however, with the Gulf scoured down to the Yucatan the moisture is going to be the limiting factor this time around. Granted mid-upper 50 dewpoints may pool in the vicinity of the dryline/cold front in SW KS, and models show storms shooting up during the evening-overnight, however, the lack of deeper moisture should preclude what would have actually looked like a solid severe wx event. Still, I would not rule out the possibility of a good storm going up in the current (fcstd) environment, however, it would have to go through a pretty stout cap and make due with pretty marginal instability. Most likely scenario is for storms on and behind the cold front, becoming a cluster overnight across KS.

Okay, enough said about Wed...Thursday keeps looking more and more possible. I first noticed it Sunday, I believe, and the trend, at least per the gfs, has the system slowing. With the cold front/dryline now forecast to be around the I-35 corridor at 7pm, upper 50s to 60 dewpoints that the gfs projects look more reasonable given Gulf modification/recovery time on the heels of very strong low-level southerly flow. By 00z, 850s are due south 45-50 kt across ECNTRL OK, with convective signals abounding. Temp. forecasts have the moist sector in the 60s for most of the afternoon, so there will probably be a fair amount of stratus and/or light shower activity, but with a dryline bulge and heating punching in from the SW, as well as strong convergence and cooling aloft associated with a vigorous shortwave coupled with favorable left exit region jet dynamics central to eastern Oklahoma may have an active afternoon-evening.

I expect a slight risk now.

 

[Donald Giuliano]

I'm getting increasingly interested in Thursday, which looks pretty decent at this point other than for the surging cold front (what else is new this year ). The NAM is hinting at the possibility of some storms ahead of the front in the warm sector or south of the triple point, which I'm really hoping will verify. It certainly appears the shear will be in place, so with CAPE values likely to be in the 1000-2000 region and little capping as the strong 700mb CAA kicks in by 00Z, things could get interesting.

 

[Chris Lott]

This day has started to look better every run. Though nothing major, some descent storms may come out of this. Fair CAPE, LI's in the -4 range in some areas coupled with descent shear, not to mention the cap looks to be gone by 00z could make for some good storms tomorrow evening. I think things will start to pop along the I-35 corridor, or just to the west of I-35 by tomorrow evening. Looks like a squall line into the evening hours that will pass through with the passage of the front.

 

[Jonathan Whitehead]

PLEASE AMEND THREAD TO INCLUDE TX

Ok tomorrows setup is normally one i wouldnt even give the benefit of a 2nd glance at but recent history being what it is and having certain area/region being in the threat area that is personal to me, I cant help but look at this a little more closely then I normally would otherwise.

SPC seems to have a general handle of whats going to happen but we all remember that day a couple weeks back on Mar 27 (see text day) with surging cold front that resulted in rotating supercells in eastern OK and SW MO. That day kinda caught everyone off gaurd a bit. Not saying that will be repeated tomorrow but just something to keep in back of head when dealing with something that has linear written all over it.

Heres what I see that sorda gets my attention. First is the decent dews in N TX. 2nd is the southerly flow at 850 then SW flow jet max arriving at 500mb. Im seeing something that might warrant a 10% tornado in TX. Sure storms will tend to be linear but that short time early on that they arent, LOOK OUT. My target is somewhere just west of DFW metroplex. Will take good hard look at this in the morning to see if its worth the 3hr drive and skipping out on hydro.

 

[Ilya Neyman]

Just taking a quick glance in between classes here but seems that cold front is aligning more N-S, just like model forecasts, and is making some eastward progress right now. The last period may have the front slowing or semi-stalling across W-CNTRL OK per latest mesonet winds/dews trends, however, I don't know how long this "slowing" will last before it picks up its speed again to the east. Latest visible does show consolidating cu along a bowing dryline segment in far SW OK, and right up on the cold front through central OK. Clouds are thinning and a lot of shear rolls in place.

Safe bet would be east of I-35, but that's all subject to speed of cold front right now.

 

[Chris Lott]

Currently into the 70's in parts of Central Tx. along and SE of I-35, with strong SE winds 20-30 mph, starting to bring some td's into the 60's. Front already through the panhandle, with temps in the 40's and N winds behind it. My only concern right now is the cloud cover over the area, holding down some of the instability. Latest vis. sat. shows clearing to the west, which will hopefully push our way, leading to better surface heating and more destabiliztion. I still believe by 00z storms fire to the NW of me, isolated at first, then quickly becoming linear, mainly a high wind and hail event.