Winter Weather in Virginia, February 26, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
246 AM EST WED FEB 26 2014

.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION THROUGH MIDDAY.
LOW PRESSURE OVER THE GREAT LAKES WILL USHER IN CANADIAN AIR TO
THE REGION THROUGH FRIDAY. A WEAK DISTURBANCE WILL SLIDE ACROSS THE
AREA SATURDAY BEFORE A MORE POTENT LOW PRESSURE SYSTEM BEGINS TO
AFFECT THE REGION EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TODAY/...
QUICK UPDATE TO ADD GREENE AND ALBEMARLE TO THE ADVISORY. NO SNOW
REPORTED YET EAST OF THE ALLEGHENY FRONT THOUGH ECHOES SOUTH OF DC
ARE MOISTENING THE COLUMN. 05Z HRRR CONTINUES TREND OF RECENT HOUR
RUNS OF A SNOW MAX IN N-CNTRL VA CENTERED OVER CULPEPER COUNTY
LOCAL AMOUNTS OF 5 INCHES. IT DOES NOT TAKE MUCH IN A COLD AIRMASS
SUCH AS THIS TO GET SEVERAL INCHES FROM BANDS AND A WARNING MAY BE
NECESSARY IN THE NOWCAST PHASE. ELSEWHERE...DEPICTION IS
CONSISTENT OF A REDUCTION IN SNOW (LESS THAN AN INCH) BETWEEN THE
ALLEGHENY FRONT AND BLUE RIDGE AND 1-3 INCHES FROM THE CENTRAL VA
FOOTHILLS TO ACROSS THE BALTIMORE-WASHINGTON METRO AREA AND SRN
MD PRIMARILY BETWEEN 10 TO 16Z.

ADJUSTED BACK END OF PRECIP WITH FOR SCATTERED FLURRIES THAT
CONTINUE THROUGH THE EARLY AFTERNOON.

PREVIOUS...
LATEST ANALYSIS SHOWS SHORTWAVE ENERGY RACING THROUGH IN A ZONAL
FLOW ALOFT ACROSS THE MIDWEST INTO THE OHIO VALLEY. A STRONGER
SHORTWAVE OVER THE UPPER MIDWEST WILL QUICKLY DROP SOUTHEAST AND
SWING THROUGH OUR AREA LATE TONIGHT INTO WEDNESDAY MORNING. DEEP
SYNOPTIC LIFT IS EXPECTED IN THE RIGHT REAR ENTRANCE OF THE UPPER-
LEVEL JET...AND THIS CAN ALREADY BE SEEN IN THE INFRARED SATELLITE
IMAGERY WITH COOLING CLOUD TOPS ACROSS THE MIDWEST AND OHIO
VALLEY. RADAR TRENDS ARE ALSO INCREASING ACROSS THESE AREAS.

CLOUDS WILL LOWER AND THICKEN OVERNIGHT AND SNOW IS EXPECTED TO
OVERSPREAD THE AREA FROM WEST TO EAST AFTER MIDNIGHT. DESPITE
LIMITED MOISTURE...FORCING SHOULD BE STRONG ENOUGH FOR SNOWFALL
ACCUMULATIONS ACROSS MOST OF THE AREA. A WINTER WEATHER ADVISORY
REMAINS IN EFFECT FOR THE WASHINGTON AND BALTIMORE METROPOLITAN
AREAS AS WELL AS THE VIRGINIA PIEDMONT AND SOUTHERN MARYLAND.
LATEST GUIDANCE CONTINUES TO SHOW THAT THE BEST POTENTIAL FOR
MESOSCALE BANDING EXISTS ACROSS THESE AREAS WITH POTENT FN VECTOR
CONVERGENCE LINING UP WITH THE AREA OF MAXIMUM DENDRITIC SNOW
GROWTH AND SATURATED CONDITIONS. SNOWFALL ACCUMULATIONS WILL
AVERAGE BETWEEN ONE AND TWO INCHES ACROSS THESE AREAS...BUT
LOCALLY HIGHER AMOUNTS AROUND THREE INCHES ARE POSSIBLE DUE TO THE
POTENTIAL OF BANDING PRECIPITATION. TEMPS WILL BE PLENTY COLD FOR
SNOW...RANGING FROM THE TEENS IN THE MOUNTAINS TO THE 20S
ELSEWHERE EARLY WEDNESDAY MORNING. THEREFORE...SNOW COVERED ROADS
AND SLIPPERY CONDITIONS ARE EXPECTED DURING THE MORNING RUSH.

A WINTER WEATHER ADVISORY IS ALSO IN EFFECT FOR PORTIONS OF WEST
VIRGINIA ALONG AND WEST OF THE ALLEGHENY FRONT DUE TO AN UPSLOPE
COMPONENT TO THE LOW-LEVEL FLOW.

HIGH PRESSURE WILL APPROACH THE AREA WEDNESDAY AFTERNOON...BUT
BLUSTERY AND COLD CONDITIONS ARE EXPECTED AS NORTHWEST WINDS
INCREASE DUE TO A STRENGTHENING GRADIENT BETWEEN THE APPROACHING
HIGH AND LOW PRESSURE DEVELOPING WELL OF THE MID-ATLANTIC COAST.
FLURRIES ARE POSSIBLE WEDNESDAY AFTERNOON AS COLD ADVECTION
COMBINING WITH THE HIGHER SUN ANGLE CAUSES SOME INSTABILITY.
HOWEVER...NO ADDITIONAL SNOWFALL ACCUMULATION IS EXPECTED.

&&

.SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/...
COLD HIGH PRESSURE WILL BUILD INTO THE MIDDLE ATLANTIC REGION
WEDNESDAY NIGHT. GUSTY NORTHWEST WINDS WILL DIMINISH AND
TEMPERATURES WILL FALL BACK INTO THE TEENS IN MOST AREAS EXCEPT
0 TO 5 ABOVE ACROSS THE ALLEGHENY FRONT. HIGH TEMPERATURES WILL
AVERAGE WELL BELOW NORMAL THURSDAY AFTERNOON WITH ANOTHER COLD
FRONT BRINGING A REINFORCING SHOT OF ARCTIC AIR THURSDAY
AFTERNOON/EVENING. OVERNIGHT LOWS THURSDAY NIGHT WILL FALL BACK TO
THE LOWER TO MIDDLE TEENS AREA WIDE EXCEPT 0 ABOVE TO 5 BELOW ZERO
ACROSS THE ALLEGHENY FRONT. GUSTY NORTHWEST WINDS MAY LEAD TO A
PERIOD OF BELOW ZERO WIND CHILLS THURSDAY NIGHT OVER WESTERN
SECTIONS.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL MOVE ACROSS THE REGION FRIDAY...MAKING IT TO THE
EAST COAST BY FRIDAY NIGHT. WINDS WILL BE LIGHT AND VARIABLE FRIDAY
THEN BECOME SOUTHERLY FRIDAY NIGHT. TEMPERATURES WILL BE ABOUT 15 TO
20 DEGREES BELOW NORMAL FRIDAY AND 5 TO 10 DEGREES BELOW NORMAL
FRIDAY NIGHT.

SOME UPPER LEVEL ENERGY WILL BRING A CHANCE FOR SOME RAIN OR SNOW
SHOWERS LATE FRIDAY NIGHT AND SATURDAY.

A STATIONARY FRONT WILL DEVELOP ALONG THE OHIO VALLEY AND INTO THE
MID-ATLANTIC REGION SUNDAY AND PERSIST INTO MONDAY. THIS FRONT WILL
BE THE FOCAL POINT OF RAIN OR SNOW...MAINLY SUNDAY NIGHT AND
MONDAY. THE EURO MODEL HAS A LOW PRESSURE SYSTEM FORMING ALONG
THIS FRONT AND MOVING NORTHEAST ALONG THE SHENANDOAH VALLEY TOWARD
PENNSYLVANIA AND NEW YORK. THE GFS MODEL HAS A LOW PRESSURE
SYSTEM FORMING ALONG THE FRONT...AS WELL...BUT TAKES THE LOW
FURTHER SOUTH AND EAST THAN THE ECMWF.

THESE DIFFERENCES MAKE IT DIFFICULT TO PINPOINT WHO WILL RECEIVE
RAIN AND WHO WILL RECEIVE SNOW. THERE IS AT LEAST A CHANCE OF EITHER
PRECIPITATION TYPE WITH A LIKELY POP OF RAIN OR SNOW MONDAY.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
CIGS/VSBYS WILL DETERIORATE EARLY WEDNESDAY MORNING AS BANDS OF
SNOW DEVELOP OVER THE TERMINALS. IFR CONDITIONS ARE EXPECTED
DURING THIS TIME. CIGS/VSBYS WILL IMPROVE LATE WEDNESDAY MORNING
AND AFTERNOON AS NORTHWEST WINDS USHER IN DRIER CONDITIONS.
HOWEVER...A FEW FLURRIES CANNOT BE RULED OUT WEDNESDAY AFTERNOON.
NORTHWEST WINDS WILL GUST AROUND 20 TO 25 KNOTS DURING THIS TIME.

VFR CONDITIONS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY NIGHT.
GUSTY NORTHWEST WINDS OF 15 TO 25 KTS WILL IMPACT THE TERMINALS
THURSDAY AFTERNOON INTO THE EVENING. WINDS WILL DIMINISH DURING
THE NIGHT.

VFR CONDITIONS FRIDAY. MVFR CONDITIONS CAN'T BE RULED OUT WITH A
CHANCE OF RAIN OR SNOW FRIDAY NIGHT THROUGH MONDAY. IF IFR
CONDITIONS DO EXIST...THERE IS A BETTER CHANCE SUNDAY NIGHT INTO
MONDAY ALONG A STATIONARY FRONT AND A DEVELOPING LOW PRESSURE
SYSTEM.

&&

.MARINE...
A SHORTWAVE WILL PASS THROUGH THE WATERS WEDNESDAY
MORNING...TRIGGERING A PERIOD OF SNOW. NW FLOW 15-20 KT SUSTAINED
BEHIND THE FRONT. SCA IN EFFECT FOR WED...CONTINUING FOR NLY FLOW
OVER ALL BUT THE WRN TRIBS WEDNESDAY EVENING.

A COLD FRONT WILL PUSH THROUGH THE WATERS ON THURSDAY BRINGING THE
LIKELIHOOD OF SCA CONDITIONS TO ALL OF THE WATERS. WINDS WILL FALL
BELOW SCA LEVELS BY THURSDAY NIGHT.

NO MARINE HAZARDS EXPECTED FRIDAY THROUGH SUNDAY. SMALL CRAFT
ADVISORIES SUNDAY NIGHT AND MONDAY WOULD DEPEND ON THE POSITION OF
A STATIONARY FRONT AND THE TRACK OF AN ATTACHED LOW PRESSURE
SYSTEM.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR DCZ001.
MD...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MDZ004>007-
     009>011-013-014-016>018.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ037>040-
     042-050>057-501-502.
WV...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR WVZ501-505.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 11 PM EST THIS
     EVENING FOR ANZ530>534-537-539>541-543.
     SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 6 PM EST THIS
     EVENING FOR ANZ535-536-538-542.

&&

UPDATE...JACKSON
PREVIOUS...BJL/KRW/KLW/HTS

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
217 AM EST WED FEB 26 2014

ANZ530>543-DCZ001-MDZ006-007-011-013-014-016>018-VAZ052>057-
261200-
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-
217 AM EST WED FEB 26 2014

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

ACCUMULATING SNOW WILL OVERSPREAD THE AREA THROUGH DAYBREAK. A
WINTER WEATHER ADVISORY IS IN EFFECT. PLEASE CONSULT THE LATEST
FORECAST AND ADVISORY FOR SPECIFIC INFORMATION.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH TUESDAY

THE WINTER WEATHER ADVISORY CONTINUES UNTIL NOON WEDNESDAY.

A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE TIDAL POTOMAC AND
MARYLAND CHESAPEAKE BAY WEDNESDAY...CONTINUING THROUGH THE EVENING
FOR PORTIONS OF THE WATERS.

WINTRY PRECIPITATION WILL BE POSSIBLE LATE SUNDAY INTO MONDAY.

SMALL CRAFT ADVISORY CONDITIONS WILL BE LIKELY THURSDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. SNOWFALL REPORTS
WOULD BE APPRECIATED.

MDZ003>005-009-010-501-502-VAZ025>031-036>040-042-050-051-501>504-
WVZ050>053-055-501>506-261200-
WASHINGTON-FREDERICK MD-CARROLL-MONTGOMERY-HOWARD-
EXTREME WESTERN ALLEGANY-CENTRAL AND EASTERN ALLEGANY-AUGUSTA-
ROCKINGHAM-SHENANDOAH-FREDERICK VA-PAGE-WARREN-CLARKE-NELSON-
ALBEMARLE-GREENE-MADISON-RAPPAHANNOCK-LOUDOUN-ORANGE-CULPEPER-
NORTHERN FAUQUIER-SOUTHERN FAUQUIER-WESTERN HIGHLAND-
EASTERN HIGHLAND-HAMPSHIRE-MORGAN-BERKELEY-JEFFERSON-HARDY-
WESTERN GRANT-EASTERN GRANT-WESTERN MINERAL-EASTERN MINERAL-
WESTERN PENDLETON-EASTERN PENDLETON-
217 AM EST WED FEB 26 2014

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

ACCUMULATING SNOW WILL CONTINUE TO SPREAD NORTH FROM CENTRAL
VIRGINIA THROUGH DAY BREAK. A WINTER WEATHER ADVISORY IS IN
EFFECT FOR AREAS EAST OF THE BLUE RIDGE EXCEPT NELSON COUNTY.
PLEASE CONSULT THE LATEST FORECAST AND ADVISORY FOR ADDITIONAL
INFORMATION.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THE WINTER WEATHER ADVISORY CONTINUES UNTIL NOON WEDNESDAY.

WINTRY PRECIPITATION WILL BE POSSIBLE LATE SUNDAY INTO MONDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. SNOWFALL REPORTS
WOULD BE APPRECIATED.

JACKSON