879  
FXUS01 KWBC 181944  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
343 PM EDT MON JUN 18 2018  
 
VALID 00Z TUE JUN 19 2018 - 00Z THU JUN 21 2018  
 
...HEAVY RAIN AND STRONG THUNDERSTORMS EXTENDING FROM THE CENTRAL  
PLAINS TO THE NORTHEAST AND MID ATLANTIC...  
 
...HEAVY RAINS AND FLASH FLOODING POSSIBLE FOR THE TEXAS COAST  
INTO SOUTHERN AND SOUTHEASTERN TEXAS...  
 
...DANGEROUS HEAT CONTINUES FOR THE MIDWEST AND OHIO VALLEY  
EXTENDING EASTWARD INTO THE NORTHEAST AND MID ATLANTIC TODAY...  
 
A SLOW-MOVING FRONTAL BOUNDARY THAT HELPED BRING HISTORIC RAINS TO  
PORTIONS OF THE UPPER MIDWEST AND UPPER GREAT LAKES REGION WILL  
CONTINUE TO DROP SOUTH, SETTLING INTO THE MID MISSISSIPPI AND OHIO  
VALLEYS OVERNIGHT. THERE THE FRONT IS EXPECTED TO REMAIN INTO  
THURSDAY, PROVIDING THE FOCUS FOR MULTIPLE ROUNDS OF SHOWERS AND  
THUNDERSTORMS THAT WILL BE ENCOURAGED BY A SERIES OF WEAK LOW  
PRESSURE SYSTEMS MOVING ALONG THE FRONT. SOME OF THESE STORMS MAY  
BE STRONG TO SEVERE AND PRODUCE HEAVY TO EXCESSIVE RAINFALL  
AMOUNTS. HEAT ADVISORIES ARE IN PLACE FROM EASTERN KANSAS INTO  
PORTIONS OF THE SOUTHERN GREAT LAKES REGION AND OHIO VALLEY, AS  
THE COMBINATION OF DAYTIME TEMPERATURES CLIMBING INTO THE 90S  
ALONG WITH HIGH HUMIDITY WILL PRODUCE HEAT INDICES OF 100 DEGREES  
OR MORE IN SOME LOCATIONS THIS AFTERNOON. EXCESSIVE HEAT WARNINGS  
REMAIN IN PLACE ACROSS SOME OF THE METROPOLITAN REGIONS, INCLUDING  
THE CHICAGO AND ST LOUIS METROS. TEMPERATURES ARE EXPECTED TO  
COME DOWN SOME ON TUESDAY, ESPECIALLY ACROSS THE SOUTHERN GREAT  
LAKES REGION. HOT AND HUMID CONDITIONS ARE FORECAST TO REMAIN IN  
PLACE FURTHER TO THE SOUTH. BY WEDNESDAY HOWEVER, INCREASING  
CLOUDS ASSOCIATED WITH DEVELOPING STORMS ALONG THE FRONT, ARE  
EXPECTED TO HELP LIMIT DAYTIME HIGHS ACROSS MUCH OF THE REGION.  
 
FURTHER TO THE EAST, HEAT ADVISORIES ARE IN EFFECT TODAY FOR  
PORTIONS OF THE NORTHEAST AND NORTHERN MID-ATLANTIC TODAY, WHERE  
HEAT INDICES ARE EXPECTED TO CLIMB INTO THE UPPER 90S TO OVER 100  
IN SOME LOCATIONS. HOWEVER, THE HEAT WILL BE SHORT-LIVED ACROSS  
MUCH OF UPSTATE NEW YORK AND NORTHERN NEW ENGLAND AS THE LEADING  
EDGE OF THE AFOREMENTIONED FRONT PUSHES SOUTHEAST FROM  
SOUTHEASTERN CANADA THIS EVENING. THIS WILL BRING COOLER  
TEMPERATURES BACK INTO THE REGION, BUT NOT BEFORE SHOWERS AND  
THUNDERSTORMS MOVE ACROSS THE REGION THIS AFTERNOON AND EVENING.  
SOME OF THESE STORMS MAY BE STRONG TO SEVERE AND PRODUCE HEAVY TO  
EXCESSIVE RAINFALL AMOUNTS.  
 
THE FRONT WILL CONTINUE TO DROP FURTHER TO THE SOUTH INTO THE MID  
ATLANTIC REGION ON TUESDAY, WHERE IT WILL CONTINUE TO PROVIDE THE  
FOCUS FOR SHOWERS AND THUNDERSTORMS AND POTENTIALLY SEVERE  
WEATHER. COOLER TEMPERATURES WILL GRADUALLY FILTER SOUTH THROUGH  
THE NORTHEAST INTO THE NORTHERN MID ATLANTIC REGION TUESDAY INTO  
WEDNESDAY.  
 
FURTHER TO THE SOUTH, SUMMERTIME CONDITIONS ARE EXPECTED TO  
PERSIST ACROSS THE SOUTHEAST AND SOUTHERN MID-ATLANTIC. DAYTIME  
HIGHS ARE EXPECTED TO CLIMB WELL INTO THE 90S TO NEAR 100 ACROSS  
THE CENTRAL INTO THE EASTERN CAROLINAS MONDAY THROUGH WEDNESDAY.  
 
A DEEP TROPICAL MOISTURE PLUME ACCOMPANYING AN UPPER LEVEL LOW AND  
WEAK SURFACE TROUGH MOVING OUT OF THE WESTERN GULF OF MEXICO IS  
EXPECTED TO PRODUCE SHOWERS AND THUNDERSTORMS, WITH HEAVY RAINFALL  
AND FLASH FLOODING POSSIBLE OVER THE NEXT FEW DAYS FROM THE TEXAS  
COAST INLAND INTO SOUTHEAST AND SOUTHERN TEXAS. THIS SYSTEM HAS  
THE POTENTIAL TO PRODUCE SEVERAL INCHES OF RAIN ACROSS PORTIONS OF  
THE REGION.  
 
OUT WEST, AN UPPER LEVEL LOW WILL CONTINUE PRODUCE UNSETTLED  
CONDITIONS AND COOLER TEMPERATURES AS IT MOVES FROM THE NORTHERN  
ROCKIES AND INTERMOUNTAIN WEST LATE MONDAY INTO TUESDAY. THIS  
SYSTEM IS EXPECTED TO MOVE OUT INTO THE NORTHERN AND CENTRAL HIGH  
PLAINS ON TUESDAY, RAISING THE THREAT FOR ORGANIZED STORMS OVER  
THE CENTRAL PLAINS TUESDAY AFTERNOON AND EVENING. THESE STORMS  
MAY BE STRONG TO SEVERE AND PRODUCE HEAVY TO EXCESSIVE RAINFALL  
AMOUNTS.  
 
PEREIRA  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
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