Severe Thunderstorm Watch 259

Issued

May 10, 2000, 10:45 AM EDT (14:45 UTC)

Expired

May 10, 2000, 5:00 PM EDT

In force

6 hr

Issued by

the Storm Prediction Center

129 
WWUS9 KMKC 101434
SEL9  

SEL9  
MKC WW 101427
NYZ000-PAZ000-LOZ000-102100-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 259
STORM PREDICTION CENTER NORMAN OK
1027 AM EDT WED MAY 10 2000

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

   WESTERN AND CENTRAL NEW YORK                           
   WESTERN AND CENTRAL PENNSYLVANIA                       
   LAKE ONTARIO                       

EFFECTIVE THIS WEDNESDAY MORNING AND AFTERNOON FROM 1045 AM UNTIL
500 PM EDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 70 STATUTE MILES
EAST AND WEST OF A LINE FROM 40 MILES SOUTH SOUTHWEST OF ALTOONA
PENNSYLVANIA TO 10 MILES NORTHEAST OF WATERTOWN NEW YORK.

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.


DISCUSSION...THUNDERSTORMS WILL INCREASE AHEAD OF STRONG COLD FRONT
AND UPPER TROUGH AS THEY APPROACH AXIS OF MOIST UNSTABLE AIR MASS
WHERE CAPES FROM 2000 TO 3000 J/KG. STEEP LAPSE RATES AND MID LEVEL
DRY INTRUSION INDICATE PRIMARY THREAT OF LARGE HAIL AND DAMAGING
DOWNDRAFTS WITH BOW ECHOES ALSO POSSIBLE.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500.  MEAN STORM
MOTION VECTOR 24035.

...ROGASH

440,0742 394,0771 394,0795 440,0771

Severe Thunderstorm Watches in Pennsylvania, 2000Severe Thunderstorm Watches in New York, 2000Every severe thunderstorm watch in 2000

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.