URGENT - IMMEDIATE BROADCAST REQUESTED 
SEVERE THUNDERSTORM WATCH NUMBER 538 
STORM PREDICTION CENTER NORMAN OK 
131 PM EDT TUE JUL 10 2001 

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
PORTIONS OF 

   DISTRICT OF COLUMBIA 
   DELAWARE                           
   MARYLAND                           
   NEW JERSEY                         
   SOUTHERN PENNSYLVANIA                       
   NORTHERN VIRGINIA                           
   EASTERN WEST VIRGINIA                      

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 145 PM UNTIL 900 PM
EDT. 

HAIL TO 1 INCH IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND
DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. 

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 75 STATUTE MILES NORTH
AND SOUTH OF A LINE FROM 65 MILES WEST OF MARTINSBURG WEST VIRGINIA TO
20 MILES SOUTH OF LAKEHURST NEW JERSEY. 

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 537... 

DISCUSSION...BAND OF THUNDERSTORMS DEVELOPING OVER CENTRAL PA AND OTHER
CELLS DEVELOPING OVER HIGHER TERRAIN OF WV EXPECTED TO INTENSIFY AND
MOVE RAPIDLY ESEWD INTO MODERATELY UNSTABLE AIR MASS. RISK OF BOW ECHO
DEVELOPMENT AND DAMAGING WINDS.  MARGINALLY SEVERE HAIL ALSO POSSIBLE. 

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 1
INCH EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS. A FEW
CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM MOTION VECTOR 28035. 

...JOHNS



URGENT - IMMEDIATE BROADCAST REQUESTED 
SEVERE THUNDERSTORM WATCH NUMBER 539 
STORM PREDICTION CENTER NORMAN OK 
249 PM EDT TUE JUL 10 2001 

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
PORTIONS OF 
  
   CONNECTICUT                        
   MASSACHUSETTS                      
   SOUTHERN NEW HAMPSHIRE
   NORTHERN NEW JERSE
   SOUTHEASTERN NEW YORK
   NORTHEASTERN PENNSYLVANIA
   RHODE ISLAND
   SOUTHERN VERMONT                            

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 300 PM UNTIL 800 PM
EDT. 

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND
DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. 

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 95 STATUTE MILES EAST
AND WEST OF A LINE FROM 60 MILES SOUTH SOUTHWEST OF POUGHKEEPSIE NEW
YORK TO 20 MILES NORTHWEST OF CONCORD NEW HAMPSHIRE. 

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 537...WW 538... 

DISCUSSION...PRESSURE FALL AXIS HAS EXTENDED SOUTHWARD INTO SERN NY AND
SRN NEW ENGLAND AND SURFACE TEMPERATURES HAVE REACHED UPPER 80S
ENHANCING INSTABILITY.  ACTIVITY DEVELOPING SWD INTO SERN NY IS LIKELY
TO CONTINUE INCREASING AND INTENSIFYING WITH A RISK OF DAMAGING WINDS
AND LARGE HAIL. 

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2
INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS.  A FEW
CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM MOTION VECTOR 27035. 

...JOHNS



URGENT - IMMEDIATE BROADCAST REQUESTED 
SEVERE THUNDERSTORM WATCH NUMBER 540 
STORM PREDICTION CENTER NORMAN OK 
342 PM EDT TUE JUL 10 2001 

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
PORTIONS OF 

   WESTERN MARYLAND
   OHIO
   SOUTHWESTERN PENNSYLVANIA
   NORTHERN AND CENTRAL WEST VIRGINIA

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 400 PM UNTIL 1100 PM
EDT. 

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 80 MPH...AND
DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 70 STATUTE MILES NORTH
AND SOUTH OF A LINE FROM 45 MILES NORTHWEST OF DAYTON OHIO TO 45 MILES
NORTHEAST OF ELKINS WEST VIRGINIA. 

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 537...WW 538...WW 539... 

DISCUSSION...BAND OF THUNDERSTORMS DEVELOPING ALONG BOUNDARY FROM SWRN
PA WNWWD INTO NERN IND EXPECTED TO BECOME INCREASINGLY SEVERE AS STRONG
SHORTWAVE TROUGH MOVES SEWD INTO GREAT LAKES REGION.  BOW ECHOS AND
ISOLATED SUPERCELLS ARE LIKELY WITH RISK OF DAMAGING WINDS THE GREATEST
THREAT.  LARGE HAIL IS ALSO LIKELY...PARTICULARLY WITH ANY SUPERCELLS
THAT DEVELOP.  RISK OF ISOLATED HIGH END WIND DAMAGE WITH SOME OF THE
BOW ECHOES. 

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2
INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 70 KNOTS.  A FEW
CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM MOTION VECTOR 29035. 

...JOHNS