742  
FXUS01 KWBC 172000  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
359 PM EDT TUE JUL 17 2018  
 
VALID 00Z WED JUL 18 2018 - 00Z FRI JUL 20 2018  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF  
THE CENTRAL PLAINS AND THE NORTHEAST STATES...  
 
...HEAVY RAIN POSSIBLE OVER PORTIONS OF ARIZONA, NORTHERN NEW  
MEXICO AND SOUTHERN COLORADO, AS WELL AS PARTS OF THE NORTHERN  
HIGH PLAINS AND THE NORTHEASTERN STATES...  
 
...HOT TEMPERATURES EXPECTED ACROSS THE SOUTHERN PLAINS AND  
SOUTHERN MISSISSIPPI VALLEY, AS WELL AS FOR THE PORTIONS OF THE  
WESTERN STATES...  
 
A LARGE FRONTAL SYSTEM CURRENTLY EXTENDS FROM NEW ENGLAND  
SOUTHWARD ACROSS THE CENTRAL APPALACHIANS AND WESTWARD THROUGH THE  
TENNESSEE VALLEY INTO THE SOUTHERN PLAINS. THE EASTERN PORTION OF  
THIS FRONT WILL CONTINUE TO SHIFT EASTWARD OFF SHORE INTO THE  
ATLANTIC THROUGH WEDNESDAY. MEANWHILE, THE SOUTHERN EXTENT OF THE  
FRONT WILL CONTINUE TO PUSH SOUTHWARD INTO THE SOUTHEAST THROUGH  
THE REMAINDER OF THE WEEK, WHILE A LOW PRESSURE SYSTEM DEEPENS  
ACROSS THE SOUTHERN PLAINS AND BEGINS TO TRANSITION NORTHEAST AS A  
WARM FRONT FOR THE REMAINDER OF THE WEEK AS WELL. DURING THIS  
TIME, SHOWER AND THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG THE  
FRONTAL BOUNDARY. A SLIGHT CHANCE OF SEVERE THUNDERSTORM POTENTIAL  
IS IN PLACE ALONG NEW ENGLAND AHEAD OF THE FRONT FOR THIS  
AFTERNOON AND TONIGHT. EXCESSIVE RAIN AND FLASH FLOODING IS ALSO  
POSSIBLE IN THIS AREA TODAY AND TONIGHT BEFORE THE FRONT SHIFTS  
OUT OVER THE ATLANTIC OCEAN.  
 
MEANWHILE, UPPER LEVEL ENERGY AND A LOW PRESSURE SYSTEM OVER THE  
NORTHERN PLAINS IS ALSO RESULTING IN THE DEVELPMENT OF STRONG  
SHOWERS AND THUNDERSTORMS. A SLIGHT CHANCE FOR BOTH EXCESSIVE RAIN  
AND SEVERE THUNDERSTORM ACTIVITY WILL REMAIN IN PLACE ACROSS  
PORTIONS OF THE CENTRAL AND NORTHERN PLAINS THROUGH TOMORROW,  
TRANSITIONING EASTWARD INTO THE MID AND UPPER MISSISSIPPI VALLEY  
BY THURSDAY. THE BEST THREAT FOR SEVERE WEATHER AND EXCESSIVE  
RAINFALL WILL BE DURING THE AFTERNOON AND EVENING HOURS DURING  
PEAK DAYTIME HEATING.  
 
A STRONG PULL OF WARM AIR FROM THE GULF OF MEXICO IS MAKING ITS  
WAY INTO THE SOUTHERN PLAINS AND LOWER MISSISIPPI VALLEY AHEAD OF  
THE ABOVE MENTIONED FRONTAL BOUNDARY. THIS IS LEADING TO EXCESSIVE  
HEAT, WITH HEAT ADVISORIES IN PLACE IN PORTIONS OF THIS AREA  
THROUGH MID WEEK. OUT WEST, MUCH OF THE PACIFIC NORTHWEST,  
CALIFORNIA, AND THE WESTERN PORTION OF THE INTERMOUNTAIN WEST ARE  
EXPERIENCING VERY DRY CONDITIONS, WHICH IS AIDING IN BOOSTING  
TEMPERATURES ACROSS THIS REGION. WIND IS ALSO ADDING CONCERNS AS  
WELL. HEAT ADVISORIES, WARNINGS, AND RED FLAG WARNINGS ARE ALL IN  
EFFECT ACROSS PORTIONS OF THESE AREAS THROUGH AT LEAST MIDWEEK.  
 
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