Tornado Watch 383

Issued

May 26, 2011, 2:53 PM EDT (18:53 UTC)

Expired

May 26, 2011, 10:00 PM EDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The State College radar (KCCX), 55 km from the middle of the area, began a volume at 18:55 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Two or more tornadoes

40%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

30%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

50%

One or more hailstones of 2 inches or more

40%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 979May 26, 11:55 AM EDT
• Mesoscale Discussion 987May 26, 5:49 PM EDT
• Mesoscale Discussion 991May 26, 8:54 PM EDT

165 
WWUS20 KWNS 261852
SEL3
SPC WW 261852
PAZ000-270200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 383
NWS STORM PREDICTION CENTER NORMAN OK
250 PM EDT THU MAY 26 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       CENTRAL AND EASTERN PENNSYLVANIA

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 250 PM UNTIL
1000 PM EDT.

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

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 50 MILES NORTH NORTHEAST OF
WILLIAMSPORT PENNSYLVANIA TO 15 MILES WEST SOUTHWEST OF
HAGERSTOWN MARYLAND.  FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 379...WW 380...WW
381...WW 382...

DISCUSSION...TSTMS ARE EXPECTED TO DEVELOP WITHIN THE NEXT HOUR
ALONG NNE-SSW ORIENTED CONFLUENCE BAND THAT HAS BECOME ESTABLISHED
OVER CNTRL PA THIS AFTERNOON.  E OF THIS BOUNDARY...AIR MASS IS WARM
AND MOIST WITH MLCAPE VALUES OF 2000-3000 J/KG.  CURRENT STATE
COLLEGE PA VAD SHOWS A VERTICALLY VEERING WIND PROFILE THROUGH THE
LOWEST 1-2 KM AGL WITH 40-50 KT SWLY FLOW ABOVE 3 KM AGL.  AS
SUCH...SETUP WILL FAVOR THE DEVELOPMENT OF SUPERCELLS CAPABLE OF
VERY LARGE HAIL AND DAMAGING WINDS.  T-TD SPREADS DECREASE WITH EWD
EXTENT FROM CONFLUENCE ZONE...AND SURFACE WINDS BACK TO SLY/SSELY.
THUS...ANY SUPERCELLS THAT CAN EVOLVE WILL HAVE AN INCREASED THREAT
FOR TORNADOES WHILE MOVING NEWD INTO THE MORE MOIST AND MORE
STRONGLY SHEARED ENVIRONMENT IN PLACE ACROSS THE ERN HALF OF THE
STATE.

AVIATION...TORNADOES AND 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 24030.


...MEAD

Tornado Watches in Pennsylvania, 2011Every tornado watch in 2011

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; radar from the NEXRAD Level II archive.