U.S. Severe Weather Forecast (Convective Outlook)

Day Three

acus02 kwns 171722 
Storm Prediction Center ac 171721 

Day 2 convective outlook 
National Weather Service Storm Prediction Center Norman OK 
1121 am CST Wednesday Dec 17 2014 

Valid 181200z - 191200z 

..there is a marginal risk of severe thunderstorms over parts of the Edwards 
Plateau and brush country of Texas... 

A few marginally severe storms may develop over parts of the Edwards 
Plateau and brush country of Texas on Thursday night. 

A series of progressive shortwave troughs will persist over the 
Continental U.S. On Thursday. A lead impulse will race eastward from the Ozark Plateau to 
the mid-Atlantic...while an upstream trough shifts from southern/Baja California California 
towards the Rio Grande Valley in Texas. In the wake of the lead 
shortwave impulse moving east from the Ozark Plateau...surface dew 
points at or above 60 degree f will be confined to the Gulf coastal plain S of 
a quasi-stationary front. This front should oscillate nwwd into 
parts of the brush country early Friday in advance of the latter 

Although low-level mass response should be moderate at most with the 
Thursday night shortwave trough...isentropic lift north of the front in 
conjunction with middle-level DCVA will Foster an expanding convective 
plume across parts of central/srn/ern Texas. The greatest potential 
buoyancy should lie on the western periphery of this broad area of 
showers and embedded thunderstorms near the Rio Grande Valley adjacent to 
the Edwards Plateau and brush country. Here...mid-level lapse rates 
will initially be rather steep with an eml emanating from the 
Mexican plateau. Although convection should largely be rooted from 
elevated parcels...robust cloud-bearing shear may support a few 
rotating updrafts capable of severe hail. Predominant cluster Mode 
and weak buoyancy should limit the overall risk. 

.Grams.. 12/17/2014