445  
ACUS01 KWNS 101938  
SWODY1  
SPC AC 101936  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0136 PM CST FRI NOV 10 2017  
 
VALID 102000Z - 111200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
THE RISK FOR SEVERE STORMS APPEARS NEGLIGIBLE THROUGH TONIGHT.  
   
..20Z OUTLOOK UPDATE
 
 
   
..FLORIDA
 
 
ON THE SOUTHERN PERIPHERY OF EXPANSIVE COLD SURFACE RIDGING NOW  
CENTERED OVER THE UPPER GREAT LAKES REGION, AN INFLUX OF COOLER AND  
DRIER SURFACE-BASED AIR IS ONGOING ACROSS THE PENINSULA. MODELS  
SUGGEST THAT THIS MAY BEGIN TO WEAKEN BY LATE TONIGHT, AS MID-LEVEL  
HEIGHTS SLOWLY RISE ACROSS MUCH OF THE SOUTHEAST, TO THE SOUTH OF  
THE RETREATING MID-LATITUDE WESTERLIES. ON THE STALLING LEADING  
EDGE OF THE ASSOCIATED BROAD NEAR SURFACE BAROCLINIC ZONE, AN AREA  
OF SUSTAINED LOW-LEVEL CONVERGENCE HAS MAINTAINED CONVECTIVE  
DEVELOPMENT NEAR COASTAL AREAS TO THE NORTH OF PALM BEACH.  
RECENTLY, AT LEAST ONE SHORT-LIVED INTENSIFICATION OF ACTIVITY HAS  
BEEN STRONG ENOUGH TO RESULT IN LIGHTNING PRODUCTION, BUT RELATIVELY  
WARM AND DRY AIR THROUGH A DEEP MID/UPPER TROPOSPHERIC LAYER  
(EVIDENT IN MORNING SOUNDINGS) IS TENDING TO SUPPRESS CONVECTION,  
AND MAY CONTINUE TO DO SO, GIVEN THE LACK OF MID/UPPER FORCING FOR  
ASCENT, PARTICULARLY INLAND OF THE IMMEDIATE COAST.  
   
..PACIFIC NORTHWEST
 
 
AS A DEAMPLIFYING UPPER TROUGH PROGRESSES INLAND OF THE OREGON COAST  
THIS AFTERNOON, ANY APPRECIABLE POTENTIAL FOR THUNDERSTORM ACTIVITY  
SEEMS LIKELY TO DIMINISH TO THE WEST OF THE CASCADES. WHILE AN  
ISOLATED/BRIEF THUNDERSTORM MAY NOT BE COMPLETELY OUT OF THE  
QUESTION THIS AFTERNOON AND EVENING, BOTH WEST OF THE CASCADES AND  
AREAS EASTWARD INTO THE INTERMOUNTAIN REGION, GIVEN THE LACK OF  
ACTIVITY TO THIS POINT, LINGERING UNCERTAINTIES CONCERNING BOTH  
DEVELOPMENT AND COVERAGE SEEM TOO LARGE TO MAINTAIN 10 PERCENT  
THUNDERSTORM PROBABILITIES.  
 
..KERR.. 11/10/2017  
   
PREV DISCUSSION
 
/ISSUED 0953 AM CST FRI NOV 10 2017/  
   
..SOUTHEAST FL
 
 
OFFSHORE CONVERGENCE APPEARS MAXIMIZED EAST OF MARTIN COUNTY PER  
VISIBLE SATELLITE IMAGERY. 12Z CAMS ARE HIGHLY CONSISTENT IN  
SIMULATING ISOLATED CONVECTION DEVELOPING TO THE SOUTHWEST WITHIN  
THIS CONFLUENCE BAND. ALTHOUGH MID-LEVEL LAPSE RATES WILL BE WEAK  
(AROUND 6 C/KM), A BRIEF THUNDERSTORM IS POSSIBLE IN THE EARLY  
EVENING CENTERED ON PALM BEACH COUNTY.  
   
..PACIFIC NORTHWEST
 
 
SHORTWAVE TROUGH OFF THE OR COAST WILL PROGRESS EAST OVER THE  
NORTHWEST TODAY. ASSOCIATED FORCING FOR ASCENT, STEEP LAPSE RATES,  
AND SCANT BUOYANCY SHOULD YIELD A RISK OF VERY ISOLATED LIGHTNING  
STRIKES MAINLY ACROSS SOUTHERN OR.  
 

 
 
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