655  
ACUS01 KWNS 030522  
SWODY1  
SPC AC 030521  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1121 PM CST SAT DEC 02 2017  
 
VALID 031200Z - 041200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF SOUTHEAST TX  
DURING THE DAY AND OVER PARTS OF THE UPPER MIDWEST DURING THE LATTER  
HALF OF THE PERIOD.  
   
..TX
 
 
LATE-EVENING WATER VAPOR IMAGERY CLEARLY DEPICTS A SHORT-WAVE TROUGH  
OVER NORTHERN MEXICO, EJECTING EAST TOWARD TX. THIS FEATURE IS  
FORECAST TO INDUCE A ZONE OF WEAK LARGE-SCALE FORCING FOR ASCENT AS  
HEIGHT FALLS SPREAD TOWARD THE LOWER SABINE RIVER VALLEY. LATEST  
GUIDANCE SUGGESTS A CORRIDOR OF 1-1.5" PW WILL ADVANCE INLAND AHEAD  
OF THE SHORT WAVE WITH MOISTENING ATOP THE BOUNDARY LAYER EXPECTED  
TO ENHANCE BUOYANCY FOR POTENTIAL DEEP CONVECTION. FORECAST  
SOUNDINGS SUGGEST PARCELS LIFTED NEAR 900MB WILL YIELD SEVERAL  
HUNDRED J/KG MUCAPE, LIKELY ADEQUATE FOR UPDRAFTS DEEP ENOUGH TO  
GENERATE LIGHTNING. FOR THESE REASONS A 10% THUNDER LINE HAS BEEN  
INTRODUCED TO SOUTHEAST TX. THUNDERSTORM THREAT WILL WANE BY EARLY  
EVENING WITH PASSAGE OF SHORT WAVE.  
   
..UPPER MIDWEST
 
 
STRONG SHORT-WAVE TROUGH WILL MOVE ACROSS THE INTERIOR NW AS 80KT  
500MB JET TRANSLATES ACROSS NV/UT INTO CO DURING THE OVERNIGHT  
HOURS. AS THIS TROUGH APPROACHES THE HIGH PLAINS IT WILL AID A  
STRENGTHENING LLJ THAT WILL FOCUS FROM EASTERN KS INTO SOUTHWEST WI  
BY THE END OF THE PERIOD. WHILE MOISTURE WILL BE SLOW TO RETURN TO  
THIS REGION, PROFILES WILL MOISTEN AND AMIDST RELATIVELY STEEP  
MID-LEVEL LAPSE RATES. FORECAST SOUNDINGS SUGGEST ISOLATED ELEVATED  
THUNDERSTORMS ARE POSSIBLE, PRIMARILY AFTER 06Z ALONG THE NOSE OF  
LLJ WHERE WARM ADVECTION WILL BE MAXIMIZED.  
 
..DARROW/GLEASON.. 12/03/2017  
 

 
 
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