Winter Storm and Winter Weather in West Virginia, December 28 to 29, 2009

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
907 PM EST SUN DEC 27 2009

.SYNOPSIS...
A COLD FRONT WILL PASS THROUGH THE REGION TONIGHT. COLD AND BLUSTERY
CONDITIONS ARE EXPECTED BEHIND THE FRONT THROUGH TUESDAY AS HIGH
PRESSURE APPROACHES FROM THE WEST. HIGH PRESSURE WILL BUILD OVERHEAD
WEDNESDAY...BUT LOW PRESSURE WILL IMPACT THE AREA TOWARD THE END OF
THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
PREV FCST APPEARS TO BE AMPLY ON TRACK. ONLY SGFNT CHG MADE TO
GRIDS INVOLVED REDUCING SKY CVR IN THE NEAR-TERM. SKY CVR STILL
XPCD TO INCR AS UPR TROF AXIS APRCHS. PREV DISCUSSION FOLLOWS...

AN UPPER-LEVEL LOW CONTINUES TO PUSH THROUGH THE OHIO VALLEY THIS
AFTERNOON. THE UPPER-LEVEL LOW WILL MOVE PENNSYLVANIA AND UPSTATE
NEW YORK TONIGHT...BUT THE COLD FRONT ASSOCIATED WITH THIS
SYSTEM WILL PASS THROUGH OUR CWA OVERNIGHT. CLOUDS WILL INCREASE
AHEAD OF THE FRONT TONIGHT...AND SNOW SHOWERS ARE EXPECTED MAINLY
FOR LOCATIONS ALONG AND WEST OF THE ALLEGHENY FRONT. THERE MAY BE
JUST ENOUGH MOISTURE FOR ISOLATED/SCATTERED SNOW SHOWERS FOR
LOCATIONS EAST OF THE ALLEGHENY FRONT...ESPECIALLY NEAR THE MASON
DIXON LINE AND INTO EASTERN WEST VIRGINIA AFTER MIDNIGHT. EVEN
ACROSS THESE LOCATIONS...ANY PRECIPITATION AMOUNTS WILL BE LIGHT.

FOR LOCATIONS ALONG AND WEST OF THE ALLEGHENY FRONT...AN UPSLOPE
COMPONENT TO THE WIND WILL INTERACT WITH THE DYNAMICS FROM THE FRONT
TO BRING ACCUMULATING SNOW. SNOWFALL ACCUMULATIONS AROUND ONE TO
THREE INCHES ARE EXPECTED BY DAYBREAK MONDAY. A WINTER WEATHER
ADVISORY WILL BE ISSUED FOR THESE AREAS BEGINNING AT 11 PM. IT WILL
TURN OUT BREEZY BEHIND THE FRONT WITH THE STRONGEST WINDS CONFINED
TO THE HIGHER ELEVATIONS ALONG THE ALLEGHENY FRONT...GUSTS UP TO 40
MPH ARE POSSIBLE OVERNIGHT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
THE COLD FRONT WILL MOVE OFF THE COAST EARLY MONDAY MORNING. LOW
PRESSURE WILL DEVELOP ALONG THIS FRONT OFF THE NEW ENGLAND
COAST...AND IT WILL INTENSIFY AS IT HEADS UP TOWARD THE CANADIAN
MARITIMES. A STRONG PRESSURE GRADIENT BETWEEN THIS LOW AND HIGH
PRESSURE BUILDING OVER THE PLAINS WILL RESULT IN BREEZY CONDITIONS.
WIND GUSTS ACROSS MANY LOCATIONS WILL BE AROUND 30 TO 35 MPH.

MAX TEMPERATURES WILL BE CHILLIER COMPARED TO RECENT DAYS...RANGING
FROM THE LOWER AND MIDDLE 20S ACROSS THE HIGHEST ELEVATIONS TO THE
UPPER 30S AND LOWER 40S NEAR WASHINGTON AND BALTIMORE.
HOWEVER...TEMPERATURES WILL FEEL LIKE THEY ARE IN THE 20S AND LOWER
30S NEAR WASHINGTON AND BALTIMORE DUE TO THE GUSTY WINDS.

THE COMBINATION OF COLD AIR OVER THE RELATIVELY WARMER GREAT LAKES
WILL INTERACT WITH THE MOUNTAINS TO BRING MORE SNOW SHOWERS TO
LOCATIONS ALONG AND WEST OF THE ALLEGHENY FRONT. ADDITIONAL
ACCUMULATIONS AROUND ONE TO TWO INCHES ARE EXPECTED ACROSS THE
HIGHEST ELEVATIONS. A WINTER WEATHER ADVISORY IS IN EFFECT ACROSS
THESE LOCATIONS.

&&

.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
ANTHR S/WV ROUNDS THE BEND MON NGT...CROSSING NY/PA. THERE WL BE
SVRL IMPLICATIONS FM THIS-- INCREASED WNDS...A REINFORCING DOSE OF
COLD AIR...AND CONTD MTN SHSN.

MON NGT LKLY WL TURN OUT WINDIER THAN TNGT...W/ A SOLID AREA OF 40
KT WNDS AT H8...AND MDL SNDGS MIXING 30-35 KT TO THE SFC...SPCLY TWD
DAWN. WL MNTN PSBL WND ADVY IN THE HWO...AND MOSTLY HOLD GRIDS BLO
ADVY CRIT ATTM SAVE THE HIEST PKS IN THE PTMC HIGHLANDS. COMPARABLE
MOMENTUM TRANSFER WL CONT THRU MIDDAY TUE.

THESE WNDS WL BE CONDUCTING STRONG CAA...AS H8 TEMPS BTTM OUT ARND
-16C TUE AFTN...A 5 DEG C DROP FM SAME TIME MON. MOS MIN-T MON NGT
FAIRLY CLS...IN THE UPR TEENS TO MID 20S...BUT A SPREAD DVLPS IN
MAXT TUE. HV OPTED TO GO ON THE COLD SIDE OF THE ENVELOPE...OWING TO
PROGGED THRML PROFILES AND THE STRENGTH OF THE TRIGGERING VORT.
THAT/LL MEAN LOCATIONS N/W OF METRO DC/BALT WL STRUGGLE TO RISE ABV
FRZG-- BEFORE WNDS GET FACTORED IN. CHILLS WL BE INT HE TEENS AND
20S ALL DAY.

AS FOR SNW...THE FAVORED UPSLP RGNS IN PRIME SETUP FOR CONTD
NMRS-WDSPD SHSN MON NGT. ON TUE...A BIT OF DIRECTIONAL SHEAR ENTERS
THE PICTURE AS SPRAWLING SFC HIPRES BLDS FM THE CNTR OF THE CONUS.
WL FCST SCT MRNG SHSN...AND GO DRY IN THE AFTN. AMS BONE DRY /DEWPTS
IN THE LWR TEENS/ SO WATER EQUIVS SHUD BE HIGH...AT LEAST A 20/1
RATIO IF NOT HIER. TYPICALLY TRRN MAKES THE MOST OF EVERY DROP...SO
WL ADD A CPL INCHES OF SNW TO THE TALLY TMRW NGT...AND AMTS UNDER AN
INCH ON TUE.

WHILE UPSLP RGNS RECEIVE MOCLDY SKIES AND SHSN...THE DWNSLP AREAS
/MOST OF THE CWFA/ WL BE MOCLR-CLR. AS ALREADY MNTND...THE SUN WL BE
INEFFECTUAL.

TUE NGT AND WED AFORMENTIONED HIPRES WL BE THE INFLUENCING WX
FEATURE AREAWIDE. IF WE CAN DCPL...TUE NGT HAS POTL TO BE BONE
CHILLING COLD. ATTM WL KEEP WNDS GOING...WHICH WL LIMIT MIN-T TO THE
TEENS...LWR 20S IN TOWN. EVEN THO H8 TEMPS RISE ON WED...RTN SFC
FLOW WL LAG BHD...SO WONT GO FOR MUCH OF AN INCR IN TEMPS DURING THE
DAY. ANY GAINS WL BE MITIGATED BY INCR CLDS DUE TO SAID WAA.

XTNDD...REGARDING EAST COAST CYCLOGENESIS ON NEW YEARS EVE...MNTND
YDA THAT THERE/S PLENTY OF TIME FOR THINGS TO CHG.  HERE/S WHY. THE
ECMWF...WHICH WAS THE MOST SOLID MDL FOR A STORM AFFECTING CWFA...
NOW /AS OF THE 27/00Z RUN/ HAS A WK SFC LOW QUICKLY EJECTING OFF
CAPE HATTERAS TWD CP COD. BASED ON THAT SOLN...ANY QPF WUD BE LGT...
AND AFFECTING MAINLY THE DELMARVA. CASE IN PT WHY ITS UNWISE TO FLLW
ANY ONE DETERMINISTIC OP RUN ATTM.

WHAT THE GDNC DOES AGREE UPON IS LOPRES DVLPMNT IN AN ACTV SRN
STREAM WED...WHICH SHUD EJECT OFF THE CAROLINA COAST THU. AFTR
THAT...THERE ARE SOME SIZABLE TIMING/STRENGTH ISSUES TO RESOLVE...
WHICH WL ALSO DICTATE THE EXTENT WHICH COLD AIR WL BE KEPT IN PLACE.
SO...CHC POPS STILL THE WAY TO GO. HV BROADENED PTYPE TO RASN THU
TIL SOME CLARITY CAN BE GLEANED.

ONE THING THAT CAN BE DETERMINED THIS FAR OUT IS THAT SHSN LKLY ON
BACK SIDE OF SYSTM...SPCLY ACRS MTNS. WL MAKE THAT ADJUSTMENT FOR
FRI-SAT.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
FEW CHGS TO PREV AVIATION FCST MADE. CLD CVR WILL INCR AT ALL
TERMINALS AS UPR TROF AXIS PASSES BY. PSBLTY OF LIGHT SHSN MOVG
NEAR KMRB EXISTS TNGT...BUT NOT CLOSE ENUF TO JUSTIFY INCLUSION IN
TAF.

CDFNT MOVES THRU LATE TNGT AND WILL PRODUCE GUSTY WNWLY WINDS THRU
MUCH OF MON. WINDS SUBSIDE BRIEFLY LATE MON AFTN BFR A SECOND
SURGE OF COLD AIR ARRIVES IN ASSOCIATION WITH PASSING UPR TROF.
WINDS WILL INCR DRAMATICALLY MON NGT WITH GUSTS TO 40 KT PSBL
STRONG NWLY JET DESCENDS. NO CIG/VSBY RESTRICTIONS XPCD.

PSBL CSTL STORM WED NGT-THU...BUT RECEIVING MIXED SIGNALS AS TO ITS
TIMING/STRENGTH...WHICH WUD ALSO AFFECT PTYPE. STAY TUNED.

&&

.MARINE...
HIGH PRESSURE WILL MOVE OFF THE COAST THIS EVENING AND A SOUTHERLY
FLOW WILL GRADUALLY INCREASE AHEAD OF AN APPROACHING COLD FRONT.
WINDS WILL CONTINUE TO INCREASE FROM THE SOUTH-SOUTHWEST JUST AHEAD
OF THE FRONT TOWARD MONDAY MORNING. THE STRONGEST WINDS ARE EXPECTED
BEHIND THE COLD FRONT MONDAY WITH FREQUENT GUSTS AROUND 30 KNOTS.
WILL CONTINUE WITH A SMALL CRAFT ADVISORY OVER THE BAY AND LOWER
TIDAL POTOMAC BEGINNING AT 4 AM MONDAY MORNING...AND ACROSS THE REST
OF THE WATERS BEGINNING AT 7 AM MONDAY MORNING.

2ND S/WV CROSSES WATER LT MON NGT-ELY TUE MRNG...PROVIDING A
REINFORCING DOSE OF WNDS. MEAN LYR MOMENTUM TRANSFER SUGGESTS 35 KT
WELL W/IN REACH...WHICH SHUD MIX FVRBLY DUE TO AIR-WATER CONTRAST.
HWVR...DONT REALLY WISH TO RAISE A 3RD-4TH PD GLW ATTM. SO...WL POST
A SCA...KEEP WNDS IN THE GRIDS/FCST...AND MNTN POTL IN THE MARINE
SYNOPSIS/HWO. WNDS SUBSIDE TUE AFTN-NGT /LKLY THE ENDING TIMEFRAME
FOR ANY SCA/...FLLWD BY HIPRES WED.

&&

.HYDROLOGY...
BOTH RVRS THAT WERE PREVLY IN FLOOD HAVE SUBSIDED BLW FLOOD STAGE.
ALL RVR FLOOD WRNGS HAVE BEEN CANCELLED.

&&

.TIDES/COASTAL FLOODING...
AFTN HIGH TIDE YIELDED MINOR COASTAL FLOODING ALONG NRN PORTIONS
OF TIDAL POTOMAC RVR...LKLY A RESULT OF COMBINED POSITIVE TIDAL
ANOMALIES AND EXCESS WATER FROM UPSTREAM SNOW MELT/RAINFALL.

POSITIVE ANOMALIES WILL CONT THRU NEXT TWO HIGH TIDE CYCLES. GIVEN
CONTD EXCESS WATER FLOW FROM UPSTREAM...XPC OBSERVATIONS AT HIGH
TIDE TO EXCEED THRESHOLDS FOR MINOR FLOODING IN WASHINGTON DC AND
ALEXANDRIA. THUS...WILL CARRY COASTAL FLOOD ADZY LATE TNGT THRU
MON AFTN TO ENCOMPASS NEXT TWO HIGH TIDES.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...COASTAL FLOOD ADVISORY FROM 2 AM TO 6 PM EST MONDAY FOR DCZ001.
MD...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR MDZ501.
VA...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR VAZ021.
     COASTAL FLOOD ADVISORY FROM 2 AM TO 6 PM EST MONDAY FOR VAZ054.
WV...WINTER WEATHER ADVISORY UNTIL 6 AM EST TUESDAY FOR WVZ054-501-
     503.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM MONDAY TO 7 PM EST TUESDAY FOR
     ANZ531>534-537-539>541-543.
     SMALL CRAFT ADVISORY FROM 7 AM MONDAY TO 7 PM EST TUESDAY FOR
     ANZ530-535-536-538-542.

&&

UPDATE...KRAMAR
PREV DISCUSSION...LASORSA/HTS

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
935 PM EST SUN DEC 27 2009

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
281000-
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-
PATAPSCO RIVER INCLUDING BALTIMORE HARBOR-
CHESTER RIVER TO QUEENSTOWN MD-EASTERN BAY-
CHOPTANK RIVER TO CAMBRIDGE MD AND THE LITTLE CHOPTANK RIVER-
PATUXENT RIVER TO BROOMES ISLAND MD-
TANGIER SOUND AND THE INLAND WATERS SURROUNDING BLOODSWORTH
ISLAND-DISTRICT OF COLUMBIA-NORTHERN BALTIMORE-HARFORD-
SOUTHERN BALTIMORE-PRINCE GEORGES-ANNE ARUNDEL-CHARLES-ST. MARYS-
CALVERT-PRINCE WILLIAM/MANASSAS/MANASSAS PARK-FAIRFAX-
ARLINGTON/FALLS CHURCH/ALEXANDRIA-STAFFORD-SPOTSYLVANIA-
KING GEORGE-
935 PM EST SUN DEC 27 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MARYLAND PORTION OF THE
CHESAPEAKE BAY...TIDAL POTOMAC RIVER...AND ADJACENT COUNTIES IN
CENTRAL MARYLAND AND NORTHERN VIRGINIA AS WELL AS THE DISTRICT OF
COLUMBIA.

.DAY ONE...TONIGHT

A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE LOWER TIDAL POTOMAC
AND MARYLAND PORTION OF THE CHESAPEAKE BAY FROM POOLES ISLAND TO
SMITH POINT BEGINNING AT 4 AM MONDAY.

A COASTAL FLOOD ADVISORY IS IN EFFECT FOR WASHINGTON DC AND
ALEXANDRIA AFTER 2 AM.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

A SMALL CRAFT ADVISORY HAS BEEN POSTED FOR THE TIDAL POTOMAC
RIVER AND MARYLAND CHESAPEAKE BAY MONDAY THROUGH TUESDAY NIGHT.
GALE WARNINGS WILL BE POSSIBLE MONDAY NIGHT AND TUESDAY.

A COASTAL FLOOD ADVISORY CONTINUES THROUGH 6 PM FOR WASHINGTON DC
AND ALEXANDRIA.

WINDS WILL INCREASE BEHIND AN UPPER LEVEL DISTURBANCE LATE
MONDAY NIGHT...AND CONTINUE INTO TUESDAY. WIND GUSTS IN EXCESS OF
45 MPH WILL BE POSSIBLE. A WIND ADVISORY MAY BE REQUIRED.

A STORM SYSTEM FROM THE SOUTHEASTERN UNITED STATES WILL BRING A
POSSIBILITY OF SNOW TO THE REGION DURING THE SECOND HALF OF THE
WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED TODAY.

MDZ003>005-009-010-501-502-VAZ021-025>031-036>042-050-051-
WVZ050>055-501>504-281000-
WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-HIGHLAND-
AUGUSTA-ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-
NELSON-ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-FAUQUIER-LOUDOUN-
ORANGE-CULPEPER-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-PENDLETON-
HARDY-WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
935 PM EST SUN DEC 27 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN WEST VIRGINIA...
NORTHERN AND CENTRAL VIRGINIA...AND CENTRAL AND WESTERN MARYLAND
WITH THE EXCEPTION OF GARRETT COUNTY.

.DAY ONE...TONIGHT

A WINTER WEATHER ADVISORY IS IN EFFECT FOR THE FAVORED WESTERN
SLOPES BEGINNING 11 PM TONIGHT. SEE THE LATEST WINTER WEATHER
MESSAGE FOR DETAILS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

ACCUMULATING SNOW SHOWERS WILL CONTINUE THROUGH TUESDAY ACROSS WEST-
FACING SLOPES ALONG THE ALLEGHENY FRONT. WINTER WEATHER ADVISORIES
ARE IN EFFECT THROUGH MONDAY NIGHT. SEE THE LATEST WINTER WEATHER
MESSAGE FOR DETAILS.

WINDS WILL INCREASE BEHIND AN UPPER LEVEL DISTURBANCE MONDAY
NIGHT...AND CONTINUE INTO TUESDAY. WIND GUSTS IN EXCESS OF 45 MPH
WILL BE POSSIBLE...ESPECIALLY OVER THE MOUNTAINS. A WIND ADVISORY
MAY BE REQUIRED. IN ADDITION...WIND CHILLS WILL APPROACH FIVE
BELOW ZERO MONDAY NIGHT IN PORTIONS OF THE HIGHLANDS.

A STORM SYSTEM FROM THE SOUTHEASTERN UNITED STATES WILL BRING A
POSSIBILITY OF SNOW TO THE REGION DURING THE SECOND HALF OF THE
WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED TODAY.

KRAMAR