U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus01 kwns 260543 
Storm Prediction Center ac 260542 

Day 1 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1242 am CDT Tue Sep 26 2017 

Valid 261200z - 271200z 

..there is a marginal risk of severe thunderstorms over a portion 
of southeast New Mexico and far southwest Texas... 

A few strong to severe storms with hail and gusty winds are possible 
this afternoon and evening from southwest Texas through southeast 
New Mexico. 

..southwest Texas through southeast New Mexico... 

Cold front will settle south through the southern High Plains 
reaching far West Texas by early evening. East-southeasterly 
near-surface winds in the pre-frontal warm sector will advect Richer 
low-level moisture westward within the upslope flow regime, with 
MLCAPE from 500-1000 j/kg likely as the boundary layer warms. 
Potential exists for deeper forcing accompanying vorticity maxima 
rotating through base of a synoptic upper trough to affect this 
region today. Storms should redevelop over the higher terrain of 
southeast nm and far southwest Texas as the atmosphere destabilizes 
this afternoon. Easterly low-level winds veering to southwesterly 
and increasing to 35 kt at 500 mb should result in sufficient 
effective bulk shear for a few supercells capable of hail and 
locally strong wind gusts through early evening. 

.Dial/karstens.. 09/26/2017 


Mesoscale Discussion

acus11 kwns 252053 
sels mesoscale discussion 
Storm Prediction Center mesoscale discussion 252053 

Mesoscale discussion 1672 
National Weather Service Storm Prediction Center Norman OK 
0353 PM CDT Mon Sep 25 2017 

Areas affected...southern High Plains 

Concerning...severe potential...watch unlikely 

Valid 252053z - 252300z 

Probability of watch issuance...20 percent 

Summary...a few storms capable of isolated large hail and/or 
damaging wind gusts are possible this afternoon across the southern 
High Plains. 

Discussion...temperatures across the region have warmed into the 
upper 70s to low 80s under mostly clear skies, eroding any previous 
convective inhibition. Modest large-scale forcing for ascent 
combined with favorable orographic circulations has resulted in the 
development of widely scattered thunderstorms within this moderately 
unstable and uncapped environment. Sheared kinematic environment, 
characterized by southeasterly surface winds and southwesterly wind 
aloft, is favorable for a few more organized/rotating storms. 
Primary severe threat with these more organized storms is isolated 
large hail although a few strong wind gusts are also possible. 
However, current expectation is for thunderstorm coverage to remain 
widely scattered and for instances of severe weather to remain 
isolated, largely as a result of only modest instability and weak 
large-scale forcing for ascent. As such, a severe thunderstorms 
watch is not currently anticipated. 

.Mosier/Hart.. 09/25/2017 

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


Latitude...Lon 31000481 32620509 34640457 34460296 32110245 30350237 
29060294 29370418 31000481