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Watch Status Reports.
SEL4
0-
URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 644
NWS STORM PREDICTION CENTER NORMAN OK
120 PM EDT FRI JUL 31 2009
THE NWS STORM PREDICTION CENTER HAS ISSUED A
SEVERE THUNDERSTORM WATCH FOR PORTIONS OF
WESTERN CONNECTICUT
DISTRICT OF COLUMBIA
DELAWARE
MARYLAND
NEW JERSEY
SOUTHERN NEW YORK
EASTERN PENNSYLVANIA
NORTHERN VIRGINIA
COASTAL WATERS
EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 120 PM UNTIL 900
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 80
STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES EAST
NORTHEAST OF POUGHKEEPSIE NEW YORK TO 15 MILES WEST OF PATUXENT
RIVER MARYLAND. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).
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.
DISCUSSION...MESSY EVOLUTION OF THUNDERSTORMS TODAY AHEAD OF BROAD
UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT. PREFRONTAL AIR MASS
IS VERY MOIST...ALMOST TROPICAL...AND WILL BECOME MARGINAL TO
MODERATELY UNSTABLE THIS AFTERNOON. SHEAR WILL BE FAIRLY STRONG AND
SUPPORT SUPERCELLS AND LINES OF STRONGER STORMS...WITH PRIMARY
THREATS OF DAMAGING WINDS/HAIL WITHIN NEARLY UNIDIRECTIONAL WIND
PROFILES. HOWEVER...LOW LEVEL SHEAR WILL BE SUFFICIENT FOR AN
ISOLATED TORNADO WITH ANY PERSISTENT SUPERCELL. HEAVY RAINFALL WILL
BE AN ADDITIONAL HAZARD THROUGH THE EVENING.
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 450. MEAN STORM
MOTION VECTOR 25030.
...EVANS
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW4
WW 644 SEVERE TSTM CT DC DE MD NJ NY PA VA CW 311720Z - 010100Z
AXIS..80 STATUTE MILES EAST AND WEST OF LINE..
40ENE POU/POUGHKEEPSIE NY/ - 15W NHK/PATUXENT RIVER MD/
..AVIATION COORDS.. 70NM E/W /22WSW BDL - 38SSE DCA/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 450. MEAN STORM MOTION VECTOR 25030.
LAT...LON 41847161 38277522 38277816 41847472
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU4.
Watch 644 Status Report Messages:
STATUS REPORT #5 ON WW 644
VALID 312335Z - 010Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ESE NEL
TO 25 S JFK TO 15 E JFK TO 25 ESE ISP TO 55 SSW BID.
..HURLBUT..07/31/09
ATTN...WFO...OKX...BOX...ALY...LWX...PHI...
&&
STATUS REPORT FOR WS 644
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
ANZ353-355-010040-
CW
. ADJACENT COASTAL WATERS 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.
$$
STATUS REPORT #4 ON WW 644
VALID 312235Z - 312Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 W NHK TO
25 SSW ACY TO 15 S EWR TO 10 E ISP TO 50 SSW BID.
..HURLBUT..07/31/09
ATTN...WFO...OKX...BOX...ALY...LWX...PHI...
&&
STATUS REPORT FOR WS 644
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
DEC005-312340-
DE
. DELAWARE COUNTIES INCLUDED ARE
SUSSEX
$$
NJC009-025-312340-
NJ
. NEW JERSEY COUNTIES INCLUDED ARE
CAPE MAY MONMOUTH
$$
ANZ353-355-431-450-451-452-453-454-455-312340-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM
SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM
DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM
COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM
COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM
COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM
$$
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.
$$
STATUS REPORT #3 ON WW 644
VALID 312055Z - 312Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 ENE CHO
TO 35 SSW DCA TO 10 SSE DCA TO 25 E DCA TO 20 WSW DOV TO 20 N PHL
TO 10 ENE JFK TO 20 ESE BDL.
....07/31/09
ATTN...WFO...OKX...BOX...ALY...LWX...PHI...
&&
STATUS REPORT FOR WS 644
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
CTC007-011-312140-
CT
. CONNECTICUT COUNTIES INCLUDED ARE
MIDDLESEX NEW LONDON
$$
DEC001-005-312140-
DE
. DELAWARE COUNTIES INCLUDED ARE
KENT SUSSEX
$$
MDC009-011-017-037-041-312140-
MD
. MARYLAND COUNTIES INCLUDED ARE
CALVERT CAROLINE CHARLES
ST. MARYS TALBOT
$$
NJC001-005-007-009-011-015-021-023-025-029-033-312140-
NJ
. NEW JERSEY COUNTIES INCLUDED ARE
ATLANTIC BURLINGTON CAMDEN
CAPE MAY CUMBERLAND GLOUCESTER
MERCER MIDDLESEX MONMOUTH
OCEAN SALEM
$$
NYC103-312140-
NY
. NEW YORK COUNTIES INCLUDED ARE
SUFFOLK
$$
PAC101-312140-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
PHILADELPHIA
$$
VAC099-177-179-630-312140-
VA
. VIRGINIA COUNTIES INCLUDED ARE
KING GEORGE SPOTSYLVANIA STAFFORD
VIRGINIA INDEPENDENT CITIES INCLUDED ARE
FREDERICKSBURG
$$
ANZ330-340-345-350-353-355-431-450-451-452-453-454-455-533-534-
537-312140-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
LONG ISLAND SOUND EAST OF NEW HAVEN CT/PORT JEFFERSON NY
PECONIC AND GARDINERS BAYS
SOUTH SHORE BAYS FROM JONES INLET THROUGH SHINNECOCK BAY
MORICHES INLET NY TO MONTAUK POINT NY OUT 20 NM
FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM
SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM
DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM
COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM
COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM
COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #2 ON WW 644
VALID 311955Z - 312Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ENE CHO
TO 5 ENE DCA TO 20 ENE BWI TO 35 SSW ABE TO 20 SE ABE TO 10 NNW
EWR TO 20 WSW BDL.
..SPC..07/31/09
ATTN...WFO...OKX...BOX...ALY...LWX...PHI...
&&
STATUS REPORT FOR WS 644
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
CTC001-003-007-009-011-013-312040-
CT
. CONNECTICUT COUNTIES INCLUDED ARE
FAIRFIELD HARTFORD MIDDLESEX
NEW HAVEN NEW LONDON TOLLAND
$$
DEC001-003-005-312040-
DE
. DELAWARE COUNTIES INCLUDED ARE
KENT NEW CASTLE SUSSEX
$$
MDC003-009-011-015-017-029-033-035-037-041-312040-
MD
. MARYLAND COUNTIES INCLUDED ARE
ANNE ARUNDEL CALVERT CAROLINE
CECIL CHARLES KENT
PRINCE GEORGES QUEEN ANNE'S ST. MARYS
TALBOT
$$
NJC001-003-005-007-009-011-013-015-017-019-021-023-025-029-033-
035-039-312040-
NJ
. NEW JERSEY COUNTIES INCLUDED ARE
ATLANTIC BERGEN BURLINGTON
CAMDEN CAPE MAY CUMBERLAND
ESSEX GLOUCESTER HUDSON
HUNTERDON MERCER MIDDLESEX
MONMOUTH OCEAN SALEM
SOMERSET UNION
$$
NYC005-047-059-061-079-081-085-087-103-119-312040-
NY
. NEW YORK COUNTIES INCLUDED ARE
BRONX KINGS NASSAU
NEW YORK PUTNAM QUEENS
RICHMOND ROCKLAND SUFFOLK
WESTCHESTER
$$
PAC017-029-045-091-101-312040-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
BUCKS CHESTER DELAWARE
MONTGOMERY PHILADELPHIA
$$
VAC099-177-179-630-312040-
VA
. VIRGINIA COUNTIES INCLUDED ARE
KING GEORGE SPOTSYLVANIA STAFFORD
VIRGINIA INDEPENDENT CITIES INCLUDED ARE
FREDERICKSBURG
$$
ANZ330-335-338-340-345-350-353-355-430-431-450-451-452-453-454-
455-532-533-534-537-312040-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
LONG ISLAND SOUND EAST OF NEW HAVEN CT/PORT JEFFERSON NY
LONG ISLAND SOUND WEST OF NEW HAVEN CT/PORT JEFFERSON NY
NEW YORK HARBOR
PECONIC AND GARDINERS BAYS
SOUTH SHORE BAYS FROM JONES INLET THROUGH SHINNECOCK BAY
MORICHES INLET NY TO MONTAUK POINT NY OUT 20 NM
FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM
SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM
DELAWARE BAY WATERS NORTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM
COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM
COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM
COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM
CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA
$$
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.
$$
STATUS REPORT #1 ON WW 644
VALID 311910Z - 312Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 ENE CHO
TO 25 NNW DCA TO 20 NW BWI TO 35 SSE CXY TO 35 NNW ILG TO 10 E
ABE TO 20 WNW EWR TO 15 SSE POU TO 30 ENE POU.
..SPC..07/31/09
ATTN...WFO...OKX...BOX...ALY...LWX...PHI...
&&
STATUS REPORT FOR WS 644
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
CTC001-003-005-007-009-011-013-312040-
CT
. CONNECTICUT COUNTIES INCLUDED ARE
FAIRFIELD HARTFORD LITCHFIELD
MIDDLESEX NEW HAVEN NEW LONDON
TOLLAND
$$
DEC001-003-005-312040-
DE
. DELAWARE COUNTIES INCLUDED ARE
KENT NEW CASTLE SUSSEX
$$
DCC001-312040-
DC
. DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE
DISTRICT OF COLUMBIA
$$
MDC003-005-009-011-015-017-025-027-029-031-033-035-037-041-510-
312040-
MD
. MARYLAND COUNTIES INCLUDED ARE
ANNE ARUNDEL BALTIMORE CALVERT
CAROLINE CECIL CHARLES
HARFORD HOWARD KENT
MONTGOMERY PRINCE GEORGES QUEEN ANNE'S
ST. MARYS TALBOT
MARYLAND INDEPENDENT CITIES INCLUDED ARE
BALTIMORE CITY
$$
NJC001-003-005-007-009-011-013-015-017-019-021-023-025-027-029-
031-033-035-039-312040-
NJ
. NEW JERSEY COUNTIES INCLUDED ARE
ATLANTIC BERGEN BURLINGTON
CAMDEN CAPE MAY CUMBERLAND
ESSEX GLOUCESTER HUDSON
HUNTERDON MERCER MIDDLESEX
MONMOUTH MORRIS OCEAN
PASSAIC SALEM SOMERSET
UNION
$$
NYC005-047-059-061-079-081-085-087-103-119-312040-
NY
. NEW YORK COUNTIES INCLUDED ARE
BRONX KINGS NASSAU
NEW YORK PUTNAM QUEENS
RICHMOND ROCKLAND SUFFOLK
WESTCHESTER
$$
PAC017-029-045-091-101-312040-
PA
. PENNSYLVANIA COUNTIES INCLUDED ARE
BUCKS CHESTER DELAWARE
MONTGOMERY PHILADELPHIA
$$
VAC013-059-099-153-177-179-510-600-610-630-683-685-312040-
VA
. VIRGINIA COUNTIES INCLUDED ARE
ARLINGTON FAIRFAX KING GEORGE
PRINCE WILLIAM SPOTSYLVANIA STAFFORD
VIRGINIA INDEPENDENT CITIES INCLUDED ARE
ALEXANDRIA FAIRFAX FALLS CHURCH
FREDERICKSBURG MANASSAS MANASSAS PARK
$$
ANZ330-335-338-340-345-350-353-355-430-431-450-451-452-453-454-
455-530-531-532-533-534-535-536-537-312040-
CW
. ADJACENT COASTAL WATERS INCLUDED ARE
LONG ISLAND SOUND EAST OF NEW HAVEN CT/PORT JEFFERSON NY
LONG ISLAND SOUND WEST OF NEW HAVEN CT/PORT JEFFERSON NY
NEW YORK HARBOR
PECONIC AND GARDINERS BAYS
SOUTH SHORE BAYS FROM JONES INLET THROUGH SHINNECOCK BAY
MORICHES INLET NY TO MONTAUK POINT NY OUT 20 NM
FIRE ISLAND INLET NY TO MORICHES INLET NY OUT 20 NM
SANDY HOOK NJ TO FIRE ISLAND INLET NY OUT 20 NM
DELAWARE BAY WATERS NORTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE
COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM
COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20
NM
COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM
COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM
COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM
CHESAPEAKE BAY NORTH OF POOLES ISLAND MD
CHESAPEAKE BAY FROM POOLES ISLAND TO SANDY POINT MD
CHESAPEAKE BAY FROM SANDY POINT TO NORTH BEACH MD
CHESAPEAKE BAY FROM NORTH BEACH TO DRUM POINT MD
CHESAPEAKE BAY FROM DRUM POINT MD TO SMITH POINT VA
TIDAL POTOMAC FROM KEY BRIDGE TO INDIAN HEAD MD
TIDAL POTOMAC FROM INDIAN HEAD TO COBB ISLAND MD
TIDAL POTOMAC FROM COBB ISLAND MD TO SMITH POINT VA
$$
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 (10%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (50%)
|
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 (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.
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