747  
ACUS03 KWNS 070755  
SWODY3  
SPC AC 070754  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0154 AM CST SAT DEC 07 2019  
 
VALID 091200Z - 101200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS ARE NOT EXPECTED ON MONDAY.  
   
..SYNOPSIS
 
 
A DEEP UPPER TROUGH WILL LIKELY EXTEND FROM THE HUDSON BAY THROUGH  
SOUTHERN CA EARLY MONDAY MORNING. THIS UPPER TROUGH IS THEN EXPECTED  
TO GRADUALLY PIVOT EASTWARD THROUGHOUT THE DAY. AS IT DOES, STRONG  
WESTERLY/SOUTHWESTERLY WIND ALOFT WILL SPREAD EASTWARD OVER THE  
EASTERN CONUS WHILE INTENSIFYING. BY EARLY TUESDAY MORNING, THE  
UPPER TROUGH WILL LIKELY EXTEND FROM THE HUDSON BAY INTO NORTHERN  
MEXICO WITH STRONG MID-LEVEL FLOW (I.E. 90-100 KT AT 500 MB) IN  
PLACE FROM THE MID MS VALLEY INTO THE UPPER OH VALLEY.  
 
AT THE SURFACE, A LOW WILL LIKELY BE NEAR THE IL/IA BORDER AT THE  
BEGINNING OF THE PERIOD WITH A COLD FRONT STRETCHING SOUTHWESTWARD  
FROM THIS LOW INTO NORTHEAST OK. THIS COLD FRONT IS EXPECTED TO PUSH  
EASTWARD/SOUTHEASTWARD THROUGHOUT THE PERIOD, LIKELY EXTENDING FROM  
THE LOWER GREAT LAKES SOUTHWESTWARD TO THE TX COAST EARLY TUESDAY  
MORNING.  
 
SHOWERS ARE FORECAST ALONG AND IN THE WAKE OF THIS FRONT, BEGINNING  
LATE MONDAY AFTERNOON AND CONTINUING THROUGH TUESDAY MORNING. MUCH  
OF THESE SHOWERS ARE EXPECTED TO BE TOO WEAK AND/OR SHALLOW TO  
PRODUCE LIGHTNING. THE ONLY EXCEPTION IS FROM SOUTHEAST TX THROUGH  
THE MID-SOUTH, WHERE OCCASIONAL UPDRAFTS MAY BE DEEP ENOUGH TO  
SUPPORT LIGHTNING PRODUCTION. ROBUST VERTICAL SHEAR IS ANTICIPATED  
BUT WEAK INSTABILITY IS CURRENTLY EXPECTED, WHICH SHOULD PREVENT ANY  
STORMS FROM REACHING SEVERE THRESHOLDS.  
 
..MOSIER.. 12/07/2019  
 

 
 
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