U.S. Severe Weather Forecast (Convective Outlook)

Day Three

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Storm Prediction Center ac 241245 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
0745 am CDT sun may 24 2015 

Valid 241300z - 251200z 

..there is a slight risk of severe thunderstorms from East Texas across parts of 
southeast OK...la...AR...and into southern MO... 

..there is a slight risk of severe thunderstorms over parts of southeast 
Colorado...the Texas Panhandle and far western OK... 

..there is a marginal risk of severe thunderstorms over parts of the 
central/Southern Plains and into the MS valley... 

Severe thunderstorms are possible today across the southeastern 
plains and Ozark Plateau into portions of the middle and lower 
Mississippi Valley. Other strong to severe storms are possible from 
southeast Colorado into western Oklahoma. 

..East Texas into AR/MO... 
Widespread thunderstorms are affecting parts of East Texas this 
morning. This activity is expected to slowly weaken later this 
morning...but remnant mcvs and outflow boundaries will likely 
rejuvenate by middle afternoon as they track northeastward into parts 
of northern la and Arkansas. Ample low level moisture is present over 
this region...along with favorable low level and deep layer shear 
profiles for organized/rotating storms. Virtually all model 
guidance agrees on a mixture of discrete and linear Mode storms 
later today...eventually moving into southeast MO and far western 
Tennessee. Damaging winds will be the main threat with the strongest 
storms. However...forecast soundings suggest that shear profiles 
will also be conducive for isolated tornadoes in storms that can 
maintain discrete Mode. 

..southeast Colorado into western OK... 
Early visible satellite imagery shows only high clouds over parts of 
eastern Colorado and the Texas Panhandle. This area will likely see 
considerable daytime heating...along with a gradual return of low 
level moisture from the southeast. By late afternoon...forecast 
soundings suggest moderate cape values /over 1500 j/kg/...and 
sufficient deep layer shear for supercell storm structures. 
Isolated thunderstorms are expected to develop along a corridor from 
southeast Colorado into the northern/eastern Texas Panhandle...spreading into 
western OK this evening. Large hail should be the main threat in 
these storms...although an isolated tornado cannot be ruled out. 

.Hart/Gleason.. 05/24/2015 

Mesoscale Discussion

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sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 240816 

Mesoscale discussion 0738 
National Weather Service Storm Prediction Center Norman OK 
0316 am CDT sun may 24 2015 

Areas affected...N-cntrl Texas...southeastern OK 

Concerning...Tornado Watch 199...200... 

Valid 240816z - 240915z 

The severe weather threat for Tornado Watch 199...200...continues. 

Summary...ww/S 199/200 are scheduled to expire at 09z. Replacement 
ww issuance is unlikely...but local temporal extension is possible 
with a risk for strong wind gusts and perhaps a brief/weak tornado 
in association with an mesoscale convective vortex evolving north-northeast from the metroplex. 

Discussion...mesoscale convective vortex over the northern portion of the metroplex currently is 
moving north around 40 knots along the I-35 corridor. Larger-scale 
convective outflow boundary is evident in 08z surface analysis from 
Marshall to Adair County OK. It appears plausible that this mesoscale convective vortex 
should continue its northward track towards the Red River before shifting 
more northeasterly over southeastern OK. Given recent measured wind gusts to near 40 
knots in the past hour /kdal and krbd/...these may be capable of 
isolated damage. With warm sector air over northestern Texas/southeastern OK 
characterized by lower 70s surface temperatures and near 70 dew 
points...transient/weak mesovortices will remain 
possible...especially as the mesoscale convective vortex interacts with the larger-scale 
outflow boundary. 

.Grams.. 05/24/2015 

..please see www.Spc.NOAA.Gov for graphic product... 


Latitude...Lon 33219692 33799673 34339591 35019505 35549468 35649452 
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33029686 33219692