491  
ACUS03 KWNS 020716  
SWODY3  
SPC AC 020715  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0115 AM CST SAT DEC 02 2017  
 
VALID 041200Z - 051200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
THUNDERSTORMS WILL BE POSSIBLE FROM THE WESTERN GULF COAST TO THE  
UPPER MIDWEST MONDAY.  
   
..DISCUSSION
 
 
A DEEP, BROAD AREA OF CYCLONIC MID/UPPER FLOW WILL DEVELOP ACROSS  
MUCH OF THE WESTERN HALF/TWO-THIRDS OF THE COUNTRY MONDAY, AS  
MULTIPLE IMPULSES ROTATE AROUND THE PERIPHERY OF THIS FLOW REGIME.  
ONE OF THESE IMPULSES WILL BE IN THE FORM OF A RATHER STOUT  
SHORTWAVE TROUGH LIFTING NORTHEAST FROM THE CENTRAL PLAINS TOWARDS  
THE UPPER GREAT LAKES. ALONG ITS SOUTHERN/EASTERN PERIPHERY, A  
CORRIDOR OF STRONG WEST/SOUTHWESTERLY 500MB WINDS WILL ORGANIZE FROM  
THE SOUTHERN PLAINS TO THE GREAT LAKES. MEANWHILE, A SURFACE CYCLONE  
WILL LIFT NORTHEAST TOWARDS LAKE SUPERIOR, AND AN ATTENDANT SURFACE  
FRONT WILL ACCELERATE EAST/SOUTHEAST TOWARDS THE MISSISSIPPI VALLEY.  
 
AHEAD OF THIS FRONT, LOW-LEVEL MOISTURE WILL RETURN NORTHWARD, WITH  
SURFACE DEW POINTS IN THE UPPER 50S/LOWER 60S LIKELY REACHING PARTS  
OF THE OZARKS DURING THE DAY. MOST GUIDANCE SUGGESTS HEATING AHEAD  
OF THE FRONT WILL NOT BE PARTICULARLY STRONG, LIMITING SURFACE-BASED  
BUOYANCY GENERALLY AT OR BELOW 500 J/KG. HOWEVER, WHILE A SMALL  
RANGE OF UNCERTAINTY, CAPE ON THE UPPER END OF THIS POTENTIAL COULD  
YIELD AT LEAST A MARGINAL STRONG-WIND THREAT WITH A BROKEN/SHALLOW  
CONVECTIVE LINE AHEAD OF THE FRONT, CONSIDERING THE STRENGTH OF THE  
AMBIENT WIND FIELD. THERE REMAINS CONSIDERABLE UNCERTAINTY WITH THE  
AMOUNT OF LOW-LEVEL DESTABILIZATION EXPECTED, THOUGH, SUCH THAT NO  
SEVERE PROBABILITIES ARE INTRODUCED AT THIS TIME. REGARDLESS, SOME  
LOW-TOPPED THUNDERSTORMS FROM TEXAS NORTHWARD TO THE MID MISSISSIPPI  
VALLEY COULD PRODUCE GUSTY WINDS LATE MONDAY INTO THE OVERNIGHT  
HOURS.  
 
..PICCA.. 12/02/2017  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page