047  
WWUS20 KWNS 122008  
SEL8  
SPC WW 122008  
DCZ000-MDZ000-VAZ000-WVZ000-CWZ000-130300-  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
SEVERE THUNDERSTORM WATCH NUMBER 448  
NWS STORM PREDICTION CENTER NORMAN OK  
410 PM EDT SAT AUG 12 2017  
 
THE NWS STORM PREDICTION CENTER HAS ISSUED A  
 
* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF  
DISTRICT OF COLUMBIA  
MARYLAND  
NORTHERN AND EASTERN VIRGINIA  
FAR EASTERN WEST VIRGINIA  
COASTAL WATERS  
 
* EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 410 PM UNTIL  
1100 PM EDT.  
 
* PRIMARY THREATS INCLUDE...  
ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE  
ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE  
 
SUMMARY...STORMS MAY CONTINUE TO INCREASE AND INTENSIFY FROM  
NEAR-MOUNTAIN AREAS OF MARYLAND AND WEST VIRGINIA INTO ADDITIONAL  
PARTS OF MARYLAND, NORTHERN/EASTERN VIRGINIA AND THE DC METRO  
VICINITY. BOUTS OF SEVERE HAIL AND WIND WILL BE POSSIBLE AS STORMS  
SPREAD EAST/SOUTHEASTWARD.  
 
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 45  
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 15 MILES SOUTH OF  
MARTINSBURG WV TO 40 MILES EAST SOUTHEAST OF BALTIMORE MD. FOR A  
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE  
UPDATE (WOUS64 KWNS WOU8).  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE  
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.  
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING  
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE  
WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE  
TORNADOES.  
 

 
 
OTHER WATCH INFORMATION...CONTINUE...WW 447...  
 
AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO  
1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A  
FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM MOTION VECTOR  
28025.  
 
...GUYER  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page