765  
ACUS48 KWNS 100942  
SWOD48  
SPC AC 100941  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0341 AM CST FRI NOV 10 2017  
 
VALID 131200Z - 181200Z  
   
..DISCUSSION
 
 
MEDIUM-RANGE MODELS APPEAR TO BE IN FAIRLY GOOD AGREEMENT THROUGH  
DAY 5, IN DEPICTING TRANSITION TO A QUASI-ZONAL FLOW PATTERN ALOFT  
AS AN EASTERN U.S. TROUGH MOVES OFFSHORE DURING DAY 4 (MONDAY 11-13)  
AND A SECOND TROUGH WEAKENS AS IT MOVES INLAND ACROSS THE NORTHWEST.  
ON DAY 5 (TUESDAY 11-12), WITH THE EASTERN TROUGH OFFSHORE AND THE  
WESTERN TROUGH WEAKENING AS IT CROSSES THE ROCKIES, FLOW WILL REMAIN  
PREDOMINANTLY WESTERLY ALOFT.  
 
MODELS BEGIN TO DIVERGE IN AN INCREASINGLY SUBSTANTIAL WAY STARTING  
DAY 6 (WEDNESDAY 11-13), AS THE NEXT NORTHEASTERN PACIFIC UPPER  
TROUGH BEGINS MOVING INLAND. TIMING/AMPLITUDE/SPEED OF THE INLAND  
ADVANCE OF THIS TROUGH IS MARKEDLY DIFFERENT WITHIN THE GFS AS  
COMPARED TO THE ECMWF, AND BOTH DIFFER FAIRLY SUBSTANTIALLY FROM THE  
RUNS FROM 24 HOURS PRIOR. WITH SEVERE RISK UNLIKELY THROUGH DAY 6,  
AND THEN BECOMING HIGHLY UNCERTAIN BEYOND, GIVEN THE DIFFERENCES IN  
EVOLUTION OF THE PATTERN -- BOTH SURFACE AND ALOFT -- AS THE STORM  
SHIFTS EAST OF THE ROCKIES, NO OUTLOOK AREAS WILL BE INCLUDED THIS  
FORECAST.  
 
..GOSS.. 11/10/2017  
 
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