258  
FXUS01 KWBC 051850  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
149 PM EST MON NOV 05 2018  
 
VALID 00Z TUE NOV 06 2018 - 00Z THU NOV 08 2018  
 
...SEVERE THUNDERSTORMS ARE EXPECTED THIS EVENING AND OVERNIGHT  
FROM THE LOWER MISSISSIPPI VALLEY TO THE TENNESSEE VALLEY...  
 
...HEAVY RAIN AND SOME FLASH FLOODING IS EXPECTED FOR PORTIONS OF  
THE OHIO AND TENNESSEE VALLEYS THROUGH TONIGHT...  
 
...MUCH COLDER TEMPERATURES WILL BE DROPPING SOUTH ACROSS THE  
PLAINS AND MIDWEST THROUGH THE MIDDLE OF THE WEEK...  
 
A FRONTAL SYSTEM EJECTING OUT ACROSS THE CENTRAL PLAINS WILL  
ADVANCE THROUGH THE LOWER MISSISSIPPI AND TENNESSEE VALLEYS THIS  
EVENING AND THE OVERNIGHT PERIOD. INCREASING SOUTHERLY FLOW AHEAD  
OF THE FRONT WILL DRAW VERY MOIST AND INCREASINGLY UNSTABLE AIR  
NORTH UP FROM THE GULF COAST REGION, WHICH WILL SET THE STAGE FOR  
WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY. IN FACT, SEVERE  
THUNDERSTORMS CAPABLE OF PRODUCING DAMAGING WINDS AND TORNADOES  
ARE EXPECTED ACROSS MUCH OF THE LOWER MISSISSIPPI AND TENNESSEE  
VALLEY REGION THROUGH TONIGHT, AND AS A RESULT THE STORM  
PREDICTION CENTER CONTINUES TO HIGHLIGHT AN ENHANCED RISK AREA OF  
SEVERE WEATHER WHICH INCLUDES AREAS OF SOUTHEAST ARKANSAS,  
NORTHERN MISSISSIPPI, NORTHWEST ALABAMA AND MUCH OF WESTERN AND  
CENTRAL TENNESSEE. A SLIGHT RISK AREA OF SEVERE WEATHER THEN  
EXPANDS OUTWARD TO INCLUDE THE REMAINDER OF THE LOWER MISSISSIPPI  
AND TENNESSEE VALLEY REGION THROUGH TONIGHT.  
 
IN ADDITION TO SEVERE THUNDERSTORMS, THERE IS THE THREAT FOR HEAVY  
RAINS AND FLASH FLOODING, WITH THE WEATHER PREDICTION CENTER  
HIGHLIGHTING A SLIGHT RISK FOR EXCESSIVE RAINFALL ACROSS PORTIONS  
OF THE TENNESSEE AND OHIO VALLEYS THROUGH TONIGHT. THE FRONT THAT  
WILL BE DRIVING THE THREAT OF HEAVY RAINFALL AND SEVERE WEATHER  
WILL CONTINUE TO MOVE EAST, WITH SHOWERS AND STORMS MOVING FROM  
THE MIDWEST INTO THE EASTERN U.S. ON TUESDAY. AGAIN, THERE IS THE  
POTENTIAL FOR SOME STORMS TO BECOME STRONG TO SEVERE, WITH THE  
STORM PREDICTION CENTER INDICATING A SLIGHT RISK FOR SEVERE  
WEATHER FOR A PORTION OF THE SOUTHEAST NORTHWARD INTO THE  
MID-ATLANTIC REGION GOING THROUGH TUESDAY EVENING. THE COLD FRONT  
WILL MOVE OFFSHORE MOST OF THE EAST COAST TUESDAY NIGHT, HOWEVER  
THE SAME BOUNDARY WILL BE SLOWING DOWN AND AT LEAST TEMPORARILY  
STALLING OUT ACROSS PORTIONS OF THE GULF COAST STATES GOING INTO  
WEDNESDAY WHICH WILL MAINTAIN THE THREAT FOR SHOWERS AND  
THUNDERSTORMS HERE.  
 
BACK TO THE WEST, SOME RAIN AND SNOW WILL ACCOMPANY A FRONTAL  
SYSTEM ADVANCING EAST ACROSS THE UPPER MIDWEST THROUGH TONIGHT AND  
EARLY TUESDAY. BEHIND THE SYSTEM, MUCH COLDER AIR WILL SPILL  
SOUTHEAST FROM SOUTHERN CANADA AND DOWN ACROSS THE NORTHERN AND  
CENTRAL PLAINS THROUGH THE MIDDLE OF THE WEEK, RESULTING IN SOME  
WELL-BELOW NORMAL DAYTIME HIGHS EAST OF THE NORTHERN ROCKIES AND  
ACROSS ESPECIALLY THE DAKOTAS FOR TUESDAY AND WEDNESDAY. AS THE  
FRONT BANKS UP ALONG THE EASTERN SLOPES OF THE NORTHERN ROCKIES,  
THIS WILL ENCOURAGE PERIODS OF SOME ACCUMULATING SNOW, WITH SOME  
LOCALLY HEAVY ACCUMULATIONS POSSIBLE FROM THE RANGES OF NORTHERN  
IDAHO AND WESTERN MONTANA TO WESTERN WYOMING.  
 
DRY CONDITIONS WILL CONTINUE ACROSS MUCH CALIFORNIA, THE SOUTHWEST  
AND THE GREAT BASIN. LOW DAYTIME RELATIVE HUMIDITIES, ALONG WITH  
WINDY CONDITIONS ARE EXPECTED TO ELEVATE FIRE WEATHER CONDITIONS  
FOR PORTIONS OF THE NORTHERN SACRAMENTO VALLEY IN CALIFORNIA  
THROUGH TUESDAY.  
 
ORRISON  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
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