Strong Cold front pushing through New England 9/9/08

[Hurricanewatcher2007]

There is a strong cold front thats going to be pushing through NE this afternoon. May produce supercells with a Isolated Tornado Here in Maine.

Local Weather Statement:

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAY ME
455 AM EDT TUE SEP 9 2008

MEZ007>009-012>014-018>028-NHZ001>010-013-014-100900-
NORTHERN OXFORD-NORTHERN FRANKLIN-CENTRAL SOMERSET-SOUTHERN OXFORD-
SOUTHERN FRANKLIN-SOUTHERN SOMERSET-INTERIOR YORK-
INTERIOR CUMBERLAND-ANDROSCOGGIN-KENNEBEC-INTERIOR WALDO-
COASTAL YORK-COASTAL CUMBERLAND-SAGADAHOC-LINCOLN-KNOX-COASTAL WALDO-
NORTHERN COOS-SOUTHERN COOS-NORTHERN GRAFTON-NORTHERN CARROLL-
SOUTHERN GRAFTON-SOUTHERN CARROLL-SULLIVAN-MERRIMACK-BELKNAP-
STRAFFORD-INTERIOR ROCKINGHAM-COASTAL ROCKINGHAM-
455 AM EDT TUE SEP 9 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MAINE...CENTRAL NEW
HAMPSHIRE...NORTHERN NEW HAMPSHIRE AND SOUTHEASTERN NEW HAMPSHIRE.

.DAY ONE...TODAY AND TONIGHT

SHOWERS AND THUNDERSTORMS WILL RACE ACROSS NEW HAMPSHIRE AND WESTERN
MAINE. A FEW OF THE THUNDERSTORMS MAY CONTAIN DAMAGING WINDS.
THERE IS ALSO THE SMALL RISK OF AN ISOLATED TORNADO.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED. SPOTTERS ARE
ENCOURAGED TO CALL OR RADIO IN THEIR REPORTS.

$$

Storm Prediction Center Statement:

SPC AC 090537

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1237 AM CDT TUE SEP 09 2008

VALID 091200Z - 101200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM PARTS OF NEW ENGLAND INTO
THE MID ATLANTIC STATES...

...THERE IS A SLGT RISK OF SVR TSTMS OVER S FL AND THE KEYS...

...SYNOPSIS...

MOBILE UPPER TROUGH OVER THE GREAT LAKES WILL DE-AMPLIFY SLIGHTLY
WHILE LIFTING NEWD ALONG THE ST. LAWRENCE VALLEY. SUBSTANTIAL
HEIGHT FALLS AND A 60-80 KT MIDLEVEL JET STREAK WILL ATTEND THIS
TROUGH ACROSS THE NERN STATES. IN THE LOW-LEVELS...SURFACE LOW OVER
SRN QUEBEC WILL DEEPEN WHILE DEVELOPING NEWD WITH TRAILING COLD
FRONT PUSHING EWD THROUGH THE NERN AND MID ATLANTIC STATES. THE
SWRN EXTENSION OF FRONT WILL TEND TO WEAKEN WITH TIME WHILE
PROGRESSING MORE SLOWLY SWD/SEWD INTO THE LOWER MS VALLEY AND SERN
STATES.

ELSEWHERE...HURRICANE IKE WILL TRACK NWWD ACROSS WRN CUBA INTO THE
SRN GULF OF MEXICO.

...NEW ENGLAND INTO THE MID ATLANTIC STATES...

LATEST MODEL GUIDANCE AND RECENT IR SATELLITE TRENDS SUGGEST THAT
CONSIDERABLE CLOUDINESS MAY TEND TO LIMIT DIABATIC HEATING TODAY
ACROSS PRE-FRONTAL WARM SECTOR...ESPECIALLY N OF THE DELMARVA.
HOWEVER...BOUNDARY LAYER MOISTURE WILL INCREASE AS SWLY LOW-LEVEL
FLOW STRENGTHENS...CONTRIBUTING TO AFTERNOON MLCAPE OF AROUND 500
J/KG OVER CNTRL NEW ENGLAND...INCREASING TO AS HIGH AS 1500 J/KG
OVER THE DELMARVA SWD ALONG THE PIEDMONT AND COASTAL PLAIN.

TSTMS ARE EXPECTED TO BE ONGOING AT 09/12Z ALONG AND AHEAD OF FRONT
FROM THE LOWER GREAT LAKES INTO TN VALLEY. STORMS SHOULD INCREASE
IN BOTH COVERAGE AND INTENSITY BY LATE MORNING/EARLY AFTERNOON AS
INFLOW AIR MASS DESTABILIZES. THE GREATEST COMBINATION OF
LARGE-SCALE FORCING FOR ASCENT AND STRONG VERTICAL SHEAR WILL EXIST
OVER THE CNTRL/LOWER HUDSON VALLEY EWD INTO NEW ENGLAND...ALONG THE
NRN EXTENSION OF ANY APPRECIABLE CONVECTIVE INSTABILITY. OVERALL
SETUP APPEARS TO FAVOR A CONVECTIVE LINE WITH EMBEDDED BOW AND
PERHAPS SUPERCELL STRUCTURES CAPABLE OF DAMAGING WINDS...SOME HAIL
AND POSSIBLY A TORNADO OR TWO.

FARTHER S...DYNAMIC FORCING FOR ASCENT AND VERTICAL SHEAR WILL TEND
TO DECREASE...BUT COMPARABLY STRONGER INSTABILITY WILL SUPPORT
STRONG/SEVERE STORMS ALONG AND AHEAD OF FRONT WITH THE POTENTIAL FOR
DAMAGING WINDS AND HAIL.

...CAROLINAS INTO THE LOWER MS VALLEY...

TSTMS WILL LIKELY INCREASE IN COVERAGE AND INTENSITY ALONG AND AHEAD
OF FRONT TODAY WITHIN WEAKLY CAPPED BUT MODERATELY UNSTABLE AIR MASS
WITH MLCAPE OF 1000-1500 J/KG. STRONGER MID AND HIGH-LEVEL FLOW
WILL EXIST N OF REGION RESULTING IN RATHER WEAK VERTICAL SHEAR.
NONETHELESS...THE POTENTIAL WILL EXIST FOR ORGANIZED STORM CLUSTERS
CAPABLE OF LOCALLY DAMAGING WIND GUSTS.

...S FL AND THE KEYS...

PER NHC GUIDANCE...HURRICANE IKE WILL MOVE NWWD ACROSS WRN CUBA INTO
THE GULF OF MEXICO. OUTER ENVELOPE OF STRONGER LOW-LEVEL SHEAR
ATTENDANT TO TROPICAL SYSTEM WILL PERSIST THROUGH MUCH OF THE
FORECAST PERIOD. AS SUCH...THE THREAT FOR SUPERCELLS AND BRIEF
TORNADOES WILL EXIST WITH ANY SPIRAL BANDS ROTATING AROUND SYSTEM.

..MEAD/JEWELL.. 09/09/2008

CLICK TO GET WUUS01 PTSDY1 PRODUCT

NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
CURRENT UTC TIME: 1234Z (8:34AM), RELOAD THIS PAGE TO UPDATE THE TIME

[Hurricanewatcher2007]

MESOSCALE DISCUSSION 2236
NWS STORM PREDICTION CENTER NORMAN OK
0735 AM CDT TUE SEP 09 2008

AREAS AFFECTED...NJ...DE...CT...DC...PORTIONS ERN PA...SRN MA...SERN
NY...RI...MD...NRN/ERN VA.

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 091235Z - 091430Z

INITIALLY ELEVATED CONVECTION HAS BECOME BETTER ORGANIZED IN BAND
FROM VT SWWD ACROSS ERN PA TO N-CENTRAL MD...AS OF 12Z. ACTIVITY
MAY BACKBUILD INTO FAVORABLY UNSTABLE AIR MASS IN NRN VA. SVR
POTENTIAL MAY INCREASE THROUGH MID-LATE MORNING AS THIS ACTIVITY
MOVES INTO PROGRESSIVELY MORE MOIST/UNSTABLE INFLOW
AIR...PARTICULARLY S OF WARM FRONT DESCRIBED BELOW. MAIN THREAT
WILL BE DAMAGING WIND. HOWEVER...FCST AMBIENT SHEAR PROFILES
SUGGEST ANY RELATIVELY DISCRETE CONVECTION ALONG/S OF WARM FRONT MAY
BECOME SUPERCELLULAR WITH LARGE HAIL AND SLGT TORNADO
POTENTIAL...GIVEN LARGER THAN USUAL LAPSE RATES AND BUOYANCY FOR
THIS REGION AND TIME OF YEAR.

SFC MESOANALYSIS AHEAD OF CONVECTIVE BAND SHOWS WARM FRONT FROM SERN
PA VICINITY RDG...ENEWD OVER NYC AREA AND CT COAST THEN SEWD OVER
ATLANTIC. THIS FRONT SHOULD LIFT NWD ACROSS SRN NEW ENGLAND THROUGH
18Z. COLD FRONT IS ANALYZED BEHIND CONVECTIVE BAND...FROM ERN KY
NEWD ACROSS WRN PA...THROUGH WEAK/ELONGATED SFC LOW OVER NERN NY.
THIS LOW IS FCST TO DEEPEN THROUGH 18Z AS UPPER GREAT LAKES
MID-UPPER SHORTWAVE TROUGH APCHS. THIS WILL RESULT IN SLGT
ENHANCEMENT TO LOW LEVEL ISALLOBARIC/ISALLOHYPSIC FIELDS AND
RESULTING STRENGTHENING OF LOW LEVEL SHEAR. DEEP-LAYER SHEAR ALSO
SHOULD STRENGTHEN JUST AHEAD OF CONVECTION AS TROUGH ALOFT
APCHS...IN SUPPORT OF ORGANIZED SVR POTENTIAL...WITH 40-50 KT
EFFECTIVE SHEAR MAGNITUDES BEING COMMON. MAIN CONCERN IS
THERMODYNAMIC....WITH THICKENING CLOUD COVER AHEAD OF ACTIVITY WILL
MUTE BUT NOT ELIMINATE DIABATIC HEATING. AS FOREGOING AIR MASS
GRADUALLY DESTABILIZES DURING NEXT FEW HOURS...FROM COMBINATION OF
THAT HEATING AND WAA...PARCELS WILL BECOME SFC BASED. MODIFIED 12Z
IAD/APG RAOBS AND MODEL SOUNDINGS SUGGEST PRE-STORM MLCAPES
1500-2000 J/KG ARE POSSIBLE S OF WARM FRONT...GIVEN MID-60S TO
LOW-70S F SFC DEW POINTS...BENEATH 7-7.5 DEG C/KM 700-500 MB LAPSE
RATES.

..EDWARDS.. 09/09/2008


ATTN...WFO...BOX...OKX...ALY...PHI...BGM...AKQ...CTP...LWX...

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37777551 37097587 38157843 39317731