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The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
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Watch Status Reports.
SEL1
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 681
NWS STORM PREDICTION CENTER NORMAN OK
235 PM EDT WED SEP 22 2010
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN MARYLAND PANHANDLE
SOUTHEAST OHIO
WESTERN AND CENTRAL PENNSYLVANIA
NORTHERN WEST VIRGINIA
EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL
1000 PM 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 NORTH AND SOUTH OF A LINE FROM 40 MILES WEST OF
WHEELING WEST VIRGINIA TO 35 MILES SOUTHEAST OF WILLIAMSPORT
PENNSYLVANIA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).
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 680...
DISCUSSION...TSTMS ARE EXPECTED TO INCREASE IN COVERAGE AND
INTENSITY THIS AFTERNOON WITHIN A STEEP LOW-LEVEL LAPSE
RATE...MODERATELY UNSTABLE ENVIRONMENT WITH MLCAPE OF 1000-1500
J/KG. REGIONAL VWPS INDICATE MODESTLY STRONG WLY TROPOSPHERIC FLOW
WHICH WILL BE SUPPORTIVE OF SPLITTING SUPERCELL STRUCTURES AND
BOWING LINE SEGMENTS WITH THE PRIMARY HAZARD BEING DAMAGING WIND
GUSTS.
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 27035.
...MEAD
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW1
WW 681 SEVERE TSTM MD OH PA WV 221835Z - 230200Z
AXIS..55 STATUTE MILES NORTH AND SOUTH OF LINE..
40W HLG/WHEELING WV/ - 35SE IPT/WILLIAMSPORT PA/
..AVIATION COORDS.. 50NM N/S /29WNW AIR - 40WNW ETX/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 27035.
LAT...LON 40978141 41687644 40097644 39388141
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU1.
Watch 681 Status Report Messages:
STATUS REPORT #4 ON WW 681
VALID 230035Z - 230140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 E HGR TO
40 ENE CXY.
..HURLBUT..09/23/10
ATTN...WFO...PBZ...RLX...CTP...
&&
STATUS REPORT FOR WS 681
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
PAC071-075-133-230140-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
LANCASTER LEBANON YORK
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #3 ON WW 681
VALID 222340Z - 230040Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 SW ZZV TO
20 S LBE TO 25 SSE AOO TO 25 W CXY TO 25 SW AVP.
..HURLBUT..09/22/10
ATTN...WFO...PBZ...RLX...CTP...
&&
STATUS REPORT FOR WS 681
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-230040-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
OHC009-111-115-121-167-230040-
OH
. OHIO COUNTIES INCLUDED ARE
ATHENS MONROE MORGAN
NOBLE WASHINGTON
$$
PAC001-009-043-051-055-057-059-071-075-107-111-133-230040-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ADAMS BEDFORD DAUPHIN
FAYETTE FRANKLIN FULTON
GREENE LANCASTER LEBANON
SCHUYLKILL SOMERSET YORK
$$
WVC017-033-049-051-061-073-077-085-091-095-103-107-230040-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
DODDRIDGE HARRISON MARION
MARSHALL MONONGALIA PLEASANTS
PRESTON RITCHIE TAYLOR
TYLER WETZEL WOOD
$$
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.
$$
STATUS REPORT #2 ON WW 681
VALID 222240Z - 222340Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 NNE ZZV
TO 20 S LBE TO 35 E AOO TO 25 SW AVP.
..HURLBUT..09/22/10
ATTN...WFO...PBZ...RLX...CTP...
&&
STATUS REPORT FOR WS 681
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-222340-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
OHC009-013-059-111-115-119-121-167-222340-
OH
. OHIO COUNTIES INCLUDED ARE
ATHENS BELMONT GUERNSEY
MONROE MORGAN MUSKINGUM
NOBLE WASHINGTON
$$
PAC001-009-041-043-051-055-057-059-071-075-099-107-111-133-
222340-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ADAMS BEDFORD CUMBERLAND
DAUPHIN FAYETTE FRANKLIN
FULTON GREENE LANCASTER
LEBANON PERRY SCHUYLKILL
SOMERSET YORK
$$
WVC017-033-049-051-061-073-077-085-091-095-103-107-222340-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
DODDRIDGE HARRISON MARION
MARSHALL MONONGALIA PLEASANTS
PRESTON RITCHIE TAYLOR
TYLER WETZEL WOOD
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 681
VALID 222020Z - 222140Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 S CAK TO
20 S DUJ TO 40 SE BFD.
FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1896.
..GRAMS..09/22/10
ATTN...WFO...PBZ...RLX...CTP...
&&
STATUS REPORT FOR WS 681
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MDC023-222140-
MD
. MARYLAND COUNTIES INCLUDED ARE
GARRETT
$$
OHC009-013-059-067-081-111-115-121-157-167-222140-
OH
. OHIO COUNTIES INCLUDED ARE
ATHENS BELMONT GUERNSEY
HARRISON JEFFERSON MONROE
MORGAN NOBLE TUSCARAWAS
WASHINGTON
$$
PAC001-003-009-013-021-027-033-035-037-041-043-051-055-057-059-
061-063-067-071-075-081-087-093-097-099-107-109-111-113-117-119-
125-129-133-222140-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
ADAMS ALLEGHENY BEDFORD
BLAIR CAMBRIA CENTRE
CLEARFIELD CLINTON COLUMBIA
CUMBERLAND DAUPHIN FAYETTE
FRANKLIN FULTON GREENE
HUNTINGDON INDIANA JUNIATA
LANCASTER LEBANON LYCOMING
MIFFLIN MONTOUR NORTHUMBERLAND
PERRY SCHUYLKILL SNYDER
SOMERSET SULLIVAN TIOGA
UNION WASHINGTON WESTMORELAND
YORK
$$
WVC009-017-029-033-049-051-061-069-073-077-085-091-095-103-107-
222140-
WV
. WEST VIRGINIA COUNTIES INCLUDED ARE
BROOKE DODDRIDGE HANCOCK
HARRISON MARION MARSHALL
MONONGALIA OHIO PLEASANTS
PRESTON RITCHIE TAYLOR
TYLER WETZEL WOOD
$$
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 (30%)
|
Probability of 1 or more wind events > 65 knots
|
Mod (30%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (30%)
|
Probability
of 1 or
more hailstones > 2 inches
|
Low (20%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (70%)
|
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.
weather.gov 
@NWSSPC
