Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
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Watch Status Reports.
SEL3
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 723...CORRECTED
NWS STORM PREDICTION CENTER NORMAN OK
705 PM EDT THU AUG 20 2009
CORRECTED FOR ENDING TIME
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
FAR WESTERN MARYLAND
WESTERN NEW YORK
WESTERN PENNSYLVANIA
NORTHERN WEST VIRGINIA
LAKE ERIE
LAKE ONTARIO
EFFECTIVE THIS THURSDAY NIGHT FROM 705 PM UNTIL MIDNIGHT EDT.
HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.
THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES SOUTH
SOUTHEAST OF MORGANTOWN WEST VIRGINIA TO 45 MILES NORTH NORTHWEST
OF ROCHESTER NEW YORK. FOR A COMPLETE DEPICTION OF THE WATCH SEE
THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).
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 721...WW 722...
DISCUSSION...ERN OH QLCS EXPECTED TO CONTINUE ENE INTO WRN
PA/NY...WHERE DEEP SHEAR SHOULD REMAIN SUFFICIENT FOR EMBEDDED
SUSTAINED STORMS/LEWPS AND SMALL SCALE BOWS WITH DMGG WIND. AHEAD
OF LINE...WEAKLY CONFLUENT LOW LVL SWLY FLOW MAY CONTINUE TO SUPPORT
DEVELOPMENT OF ISOLD STORMS THAT...GIVEN ENVIRONMENTAL SHEAR AND
MOISTURE...COULD EVOLVE INTO SMALL SUPERCELLS POSING A THREAT FOR
LOCALLY DMGG WIND...MARGINALLY SVR HAIL...AND POSSIBLY AN ISOLD
TORNADO.
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 500. MEAN STORM
MOTION VECTOR 23030.
...CORFIDI
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW3
WW 723 SEVERE TSTM MD NY PA WV LE LO 202305Z - 210400Z
AXIS..55 STATUTE MILES EAST AND WEST OF LINE..
30SSE MGW/MORGANTOWN WV/ - 45NNW ROC/ROCHESTER NY/
..AVIATION COORDS.. 50NM E/W /27NE EKN - 55NNE BUF/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 23030.
LAT...LON 39248073 43727912 43727691 39247868
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU3.
Watch 723 Status Report Messages:
STATUS REPORT #3 ON WW 723
VALID 210130Z - 210240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 NW EKN TO
25 SE PIT TO 20 NNE PIT TO 5 ENE FKL TO 15 NNE JHW TO 60 N BUF.
..BROYLES..08/21/09
ATTN...WFO...PBZ...BUF...CTP...
&&
STATUS REPORT FOR WS 723
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-210240-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
NYC003-009-029-037-051-055-073-121-210240-
NY
. NEW YORK COUNTIES INCLUDED ARE
ALLEGANY CATTARAUGUS ERIE
GENESEE LIVINGSTON MONROE
ORLEANS WYOMING
$$
PAC005-021-023-031-033-047-051-053-063-065-083-105-111-123-129-
210240-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ARMSTRONG CAMBRIA CAMERON
CLARION CLEARFIELD ELK
FAYETTE FOREST INDIANA
JEFFERSON MCKEAN POTTER
SOMERSET WARREN WESTMORELAND
$$
WVC077-093-210240-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
PRESTON TUCKER
$$
LOZ043-062-063-210240-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
HAMLIN BEACH TO SODUS BAY NY
NIAGARA RIVER TO HAMLIN BEACH NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
HAMLIN BEACH TO SODUS BAY NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
$$
-210240-
. COUNTIES INCLUDED ARE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 723
VALID 210040Z - 210140Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..BROYLES..08/21/09
ATTN...WFO...PBZ...BUF...CTP...
&&
STATUS REPORT FOR WS 723
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-210140-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
NYC003-009-013-029-037-051-055-063-073-121-210140-
NY
. NEW YORK COUNTIES INCLUDED ARE
ALLEGANY CATTARAUGUS CHAUTAUQUA
ERIE GENESEE LIVINGSTON
MONROE NIAGARA ORLEANS
WYOMING
$$
PAC003-005-019-021-023-031-033-047-051-053-059-063-065-083-105-
111-121-123-125-129-210140-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ALLEGHENY ARMSTRONG BUTLER
CAMBRIA CAMERON CLARION
CLEARFIELD ELK FAYETTE
FOREST GREENE INDIANA
JEFFERSON MCKEAN POTTER
SOMERSET VENANGO WARREN
WASHINGTON WESTMORELAND
$$
WVC049-061-077-093-210140-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
MARION MONONGALIA PRESTON
TUCKER
$$
LEZ020-040-041-061-LOZ042-043-045-063-064-065-210140-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
NIAGARA RIVER TO HAMLIN BEACH NY
HAMLIN BEACH TO SODUS BAY NY
MEXICO BAY NY TO THE ST. LAWRENCE RIVER
HAMLIN BEACH TO SODUS BAY NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
SODUS BAY TO MEXICO BAY NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
MEXICO BAY NY TO THE ST. LAWRENCE RIVER BEYOND 5NM OFF SHORELINE
TO US/CANADIAN BORDER
BUFFALO HARBOR AND THE UPPER NIAGARA RIVER
RIPLEY TO DUNKIRK NY
DUNKIRK TO BUFFALO NY
RIPLEY TO BUFFALO NY EXTENDING FROM 5NM OFF SHORELINE TO
US/CANADIAN BORDER
$$
-210140-
. COUNTIES INCLUDED ARE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 723
VALID 202340Z - 210040Z
THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA.
..BROYLES..08/20/09
ATTN...WFO...PBZ...BUF...CTP...
&&
STATUS REPORT FOR WS 723
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-210040-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
NYC003-009-013-029-037-051-055-063-073-121-210040-
NY
. NEW YORK COUNTIES INCLUDED ARE
ALLEGANY CATTARAUGUS CHAUTAUQUA
ERIE GENESEE LIVINGSTON
MONROE NIAGARA ORLEANS
WYOMING
$$
PAC003-005-019-021-023-031-033-047-051-053-059-063-065-083-105-
111-121-123-125-129-210040-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ALLEGHENY ARMSTRONG BUTLER
CAMBRIA CAMERON CLARION
CLEARFIELD ELK FAYETTE
FOREST GREENE INDIANA
JEFFERSON MCKEAN POTTER
SOMERSET VENANGO WARREN
WASHINGTON WESTMORELAND
$$
WVC049-061-077-093-210040-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
MARION MONONGALIA PRESTON
TUCKER
$$
LEZ020-040-041-061-LOZ042-043-045-063-064-065-210040-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
NIAGARA RIVER TO HAMLIN BEACH NY
HAMLIN BEACH TO SODUS BAY NY
MEXICO BAY NY TO THE ST. LAWRENCE RIVER
HAMLIN BEACH TO SODUS BAY NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
SODUS BAY TO MEXICO BAY NY BEYOND 5NM OFF SHORELINE TO
US/CANADIAN BORDER
MEXICO BAY NY TO THE ST. LAWRENCE RIVER BEYOND 5NM OFF SHORELINE
TO US/CANADIAN BORDER
BUFFALO HARBOR AND THE UPPER NIAGARA RIVER
RIPLEY TO DUNKIRK NY
DUNKIRK TO BUFFALO NY
RIPLEY TO BUFFALO NY EXTENDING FROM 5NM OFF SHORELINE TO
US/CANADIAN BORDER
$$
-210040-
. COUNTIES INCLUDED ARE
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (20%)
|
Probability of 1 or more strong (F2-F5) tornadoes
|
Low (5%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (40%)
|
Probability of 1 or more wind events > 65 knots
|
Low (10%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (40%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (10%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (80%)
|
For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The "Low" category contains probability values ranging from less than 2%
to 20% (F2-F5 tornadoes), less than 5% to 20% (all other probabilities),
"Moderate" from 30% to 60%, and "High" from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.