065  
FXUS01 KWBC 111843  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
243 PM EDT SAT AUG 11 2018  
 
VALID 00Z SUN AUG 12 2018 - 00Z TUE AUG 14 2018  
   
..HEAVY RAIN AND FLASH FLOODING A CONCERN FOR WEST TEXAS
 
 
...SHOWERS AND THUNDERSTORMS COULD BRING FLASH FLOODING TO NEW  
ENGLAND SOUTHWARD INTO THE MID-ATLANTIC...  
 
...HEAT WAVE CONTINUES ACROSS PARTS OF THE INTERMOUNTAIN WEST  
ALONG WITH CRITICAL FIRE WEATHER CONDITIONS...  
 
A MID-LEVEL CLOSED LOW CENTERED OVER TEXAS WILL AID IN BRINGING A  
PLUME OF ENHANCED MOISTURE ACROSS THE STATE. MEANWHILE, AT THE  
SURFACE, TWO QUASI-STATIONARY FRONTS WILL PROVIDE FOCUS FOR  
FUELING SHOWERS AND THUNDERSTORMS. MOST OF THE HEAVY RAINFALL CAN  
BE EXPECTED FROM THE BIG BEND OF TEXAS TO THE DALLAS-FORT WORTH  
REGION. FOR THE REST OF TODAY, EXPECT A SLIGHT RISK OF FLASH  
FLOODING ACROSS THE BIG BEND REGION. A MARGINAL RISK WILL ALSO BE  
IN PLACE FROM MOST OF WEST TEXAS AND INTO THE RED RIVER VALLEY. BY  
SUNDAY, A MODERATE RISK OF FLASH FLOODING IS POSSIBLE FOR PORTIONS  
OF WEST TEXAS. AS THE SURFACE FRONT LIFTS NORTH AS A WARM FRONT BY  
MONDAY, THE AXIS OF HEAVY RAINFALL WILL CONCENTRATE IN THE  
SOUTHERN PORTIONS OF THE CENTRAL PLAINS AND INTO THE LOWER  
MISSISSIPPI VALLEY. PARTS OF OKLAHOMA AND KANSAS COULD SEE FLASH  
FLOODING WITH THIS CONVECTION; THUS, A SLIGHT RISK HAS BEEN  
ISSUED.  
 
A MID-LEVEL TROUGH IS SLOWLY MOVING EASTWARD AND BY TOMORROW  
MORNING, THE MID-LEVEL LOW WILL PINCH OFF AND REMAIN OVER THE OHIO  
VALLEY. ONCE AGAIN, TWO BOUNDARIES AT THE SURFACE WILL FOCUS  
SHOWERS AND THUNDERSTORMS THROUGH THE REST OF THE WEEKEND. FOR  
TODAY, PORTIONS OF THE TENNESSEE VALLEY INTO THE MID-ATLANTIC CAN  
EXPECT SCATTERED SHOWERS AND THUNDERSTORMS WITH HEAVIER RAINFALL  
ACROSS NEW ENGLAND. BY SUNDAY, THE AXIS OF HEAVY RAINFALL SHIFTS  
TO THE MID-ATLANTIC SOUTHWARD INTO NORTH CAROLINA. THE CLOSED  
MID-LEVEL LOW WILL DRIFT OVER THE CENTRAL  
APPALACHIANS/MID-ATLANTIC ON MONDAY--WHICH WILL PERSEVERE THIS WET  
PATTERN FOR MUCH OF THE EAST COAST.  
 
PLENTY OF INSTABILITY AND MOISTURE ON TAP IS EXPECTED FOR THE  
SOUTHWEST. SINCE MOST OF THESE THUNDERSTORMS WILL BE DIURNALLY  
DRIVEN, SHOWERS AND THUNDERSTORMS WILL INCREASE IN COVERAGE DURING  
THE LATE AFTERNOON/EVENING. FLASH FLOODING IS A CONCERN ESPECIALLY  
FOR REGIONS PRONE TO FLOODING DUE TO TERRAIN AND URBAN AREAS.  
 
FARTHER NORTH, A HEAT WAVE CONTINUES ACROSS PARTS OF THE PACIFIC  
NORTHWEST EASTWARD INTO THE NORTHERN PLAINS. EXCESSIVE HEAT  
WARNINGS AND HEAT ADVISORIES ARE IN PLACE AS HIGH TEMPERATURES  
SOAR TO ABOVE 100 DEGREES FOR THESE AREAS. ADDITIONALLY, BECAUSE  
OF THE OPPRESSIVE HEAT AND DRY CONDITIONS, FIRE WEATHER IS A  
CONCERN FOR MANY OF THESE REGIONS. AS SUCH, RED FLAG WARNINGS ARE  
IN PLACE FROM WESTERN WASHINGTON TO NORTHWEST SOUTH DAKOTA ALONG  
WITH SOME PARTS OF NORTHERN CALIFORNIA, SOUTHERN OREGON, AND  
NORTHWEST NEVADA. A STRONG COLD FRONT WILL MOVE ACROSS THESE  
REGIONS OVER THE NEXT FEW DAYS AND WILL RELIEF TO THE OPRESSIVE  
HEAT. THE PACIFIC NORTHWEST AND NORTHERN ROCKIES CAN EXPECT HIGH  
TEMPERATURES TO BE IN THE 80S BY TOMORROW. ON MONDAY, TEMPERATURES  
ACROSS MOST OF THE MONTANA AND NORTH DAKOTA WILL DROP TO NEAR  
NORMAL OR BELOW NORMAL.  
 
REINHART  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
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