248  
FXUS01 KWBC 300804  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
404 AM EDT THU AUG 30 2018  
 
VALID 12Z THU AUG 30 2018 - 12Z SAT SEP 01 2018  
 
...HEAVY RAIN AND SEVERE WEATHER POSSIBLE FOR THE MISSISSIPPI  
VALLEY...  
   
..HEAT WAVE TO CONTINUE ACROSS THE MID-ATLANTIC AND NORTHEAST
 
 
...FIRE WEATHER CONCERNS BEGIN TO RESURFACE ACROSS THE WESTERN  
U.S....  
 
A STRONG COLD FRONT IS SLOWLY MOVING SOUTH AND EAST, STRETCHING  
FROM NEW ENGLAND TO THE CENTRAL AND SOUTHERN PLAINS. AS THIS  
BOUNDARY SLOWS AND STALLS ACROSS THE MID-ATLANTIC AND INTO THE  
MIDDLE MISSISSIPPI VALLEY TODAY, MORE ROUNDS OF SHOWERS AND  
THUNDERSTORMS ARE EXPECTED ALONG THE BOUNDARY. SOME OF THESE  
THUNDERSTORMS COULD PRODUCE LOCALLY HEAVY RAINFALL--THUS A  
MARGINAL RISK OF FLASH FLOODING IS POSSIBLE FROM THE MID ATLANTIC  
INLAND THROUGH THE TENNESSEE VALLEY TODAY.  
MEANWHILE, A PORTION OF THE FRONT ACROSS THE SOUTHERN AND CENTRAL  
PLAINS WILL SHIFT NORTHWARD AND TRANSITION INTO A WARM FRONT  
TODAY, GUIDED BY A DEVELOPING AREA OF LOW PRESSURE. AS THIS  
FRONTAL BOUNDARY CONTINUES TO TRAVERSE EASTWARD ACROSS THE PLAINS  
AND TOWARDS THE MISSISSIPPI RIVER VALLEY, THUNDERSTORMS CAPABLE OF  
PRODUCING HEAVY RAINFALL ARE FORECAST FOR TONIGHT NIGHT AND FRIDAY  
MORNING. THE COMBINATION OF HEAVY RAIN POTENTIAL AND ALREADY  
SATURATED SOILS HAVE LED TO A SLIGHT RISK OF FLASH FLOODING FOR  
THE MIDDLE MISSOURI VALLEY THIS EVENING AND OVERNIGHT. THE STORM  
PREDICTION CENTER HAS ALSO ISSUED A MARGINAL RISK OF SEVERE  
THUNDERSTORMS STRETCHING FROM SOUTHERN MINNESOTA SOUTHWARD INTO  
EASTERN KANSAS AND WESTERN MISSOURI DURING THIS TIME FRAME AS  
WELL.  
 
BY FRIDAY, THE CLUSTER OF STORMS WILL CONTINUE IMPACTING THE  
MIDDLE MISSISSIPPI VALLEY, ESPECIALLY AS THE CENTER OF LOW  
PRESSURE CONTINUES TO STRENGTHEN, AND A DEEP LAYER OF WARM MOIST  
AIR IS LIFTED NORTHWARD FROM THE GULF OF MEXICO AIDING IN STORM  
DEVELOPMENT. THIS WILL BE FURTHER EXASPERATED BY ANOTHER COLD  
FRONT DROPPING SOUTHEAST FROM CANADA INTO THE NORTHERN PLAINS,  
BRINGING WITH IT A SURGE OF COLDER AIR. THE CLASH OF THE TWO AIR  
MASSES COULD LEAD TO STRONG STORMS ACROSS THE MID AND UPPER  
MISSISSIPPI VALLEYS AS WELL AS INTO THE FAR WESTERN PLAINS. THIS  
AREA HAS BEEN OUTLINED AS BEING IN A SLIGHT RISK FOR SEVERE  
THUNDERSTORMS BY THE STORM PREDICTION CENTER FOR FRIDAY. THE  
WEATHER PREDICTION CENTER HAS ALSO OUTLINED MUCH OF THE UPPER AND  
MID MISSISSIPPI VALLEYS AS BEING IN A SLIGHT RISK FOR FLASH  
FLOODING AS WELL.  
 
WITH THE UPPER RIDGE BEING THE DOMINANT FEATURE ACROSS THE  
SOUTHEAST, TEMPERATURES ACROSS THE NORTHEAST AND MID-ATLANTIC WILL  
STILL BE WELL ABOVE NORMAL THROUGH THURSDAY. HEAT ADVISORIES AND  
EXCESSIVE HEAT WARNINGS ARE IN PLACE THROUGH THIS EVENING. BY  
FRIDAY, ONCE THE COLD FRONT PUSHES ACROSS THESE REGIONS AND STALLS  
TO THE SOUTH, TEMPERATURES WILL DROP SIGNIFICANTLY. MEANWHILE,  
PRECIPITATION WILL LINGER ACROSS THE AREA INTO THE WEEKEND. THIS  
WILL BRING HIGH TEMPERATURES DOWN--AND END THE HEAT ADVISORIES.  
 
ELSEWHERE ACROSS THE U.S., FIRE WEATHER CONCERNS WILL BE POSSIBLE  
ACROSS THE PACIFIC NORTHWEST, INTERMOUNTAIN WEST AND GREAT BASIN  
THROUGH FRIDAY. RED FLAG WARNINGS AND FIRE WEATHER WATCHES ARE IN  
PLACE ACROSS MUCH OF WYOMING, NORTHWEST COLORADO AND A SMALL  
PORTION OF UTAH THROUGH THURSDAY DUE TO LOW RELATIVE HUMIDITIES  
AND GUSTY WINDS. SOUTHWEST OREGON IS ALSO STILL UNDER AN AIR  
QUALITY ALERT DUE TO SMOKE FROM A NEARBY WILDFIRE.  
 
WIX  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab HPC Page Main Text Page