Area Forecast Discussion
Issued by NWS Sterling, VA

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000
FXUS61 KLWX 260858
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
358 AM EST MON JAN 26 2015

.SYNOPSIS...
LOW PRESSURE WILL PASS BY TO THE SOUTH TODAY. THE LOW WILL RAPIDLY
INTENSIFY AS IT MOVES OFF TO OUR NORTH AND EAST TONIGHT THROUGH
TUESDAY. HIGH PRESSURE WILL BUILD OVERHEAD WEDNESDAY BEFORE
ANOTHER CLIPPER SYSTEM SWINGS THROUGH THURSDAY INTO THURSDAY
NIGHT.

&&

.NEAR TERM /THROUGH TONIGHT/...
ENHANCED WATER VAPOR IMAGERY CONTINUES TO SHOW A RATHER VIGOROUS
UPPER SHORTWAVE TROUGH WITH ASSOCIATED SURFACE LOW TRACKING EAST
ACROSS THE VA/NC BORDER EARLY THIS MORNING. PRECIPITATION ASSOCIATED
WITH THIS CLIPPER SYSTEM WILL IMPACT THE MIDDLE ATLANTIC REGION THIS
MORNING. COLD AIR HAS BEEN SLOW TO FILTER SOUTH OVERNIGHT. FREEZING
TEMPERATURES HAVE BEEN RELEGATED MOSTLY ALONG THE MASON DIXON LINE
AND POINTS JUST SOUTH. NORTHERLY WINDS WILL INCREASE LATER THIS
MORNING INTO THIS AFTERNOON AS ENERGY TRANSFERS FROM THE CLIPPER
SYSTEM TO THE CAROLINA COAST A BIT LATER TODAY. THIS WILL EVENTUALLY
DRIVE THE COLD AIR SOUTH THROUGH THE FORECAST AREA.

PRECIPITATION FORECAST REMAINS CHALLENGING FOR THE MIDDLE ATLANTIC
REGION. SNOW WILL LIKELY PERSIST THROUGH THE MORNING HOURS FOR AREAS
WELL NORTH AND WEST OF THE METRO AREAS. RAIN WILL DEVELOP OVER THE
REMAINDER OF THE REGION. AS COLDER AIR SEEPS IN ON INCREASING
NORTHERLY WINDS...WE EXPECT RAIN TO MIX WITH AND EVENTUALLY CHANGE
TO SNOW FROM NORTH TO SOUTH. SLIPPERY TRAVEL WILL LIKELY RESULT
ESPECIALLY FOR AREAS WELL NORTH AND WEST OF THE DC METRO AREA.

AS THE CLIPPER LOW TRANSFERS TO THE COASTAL...A NORLUN TROUGH WILL
LIKELY DEVELOP AND THIS FEATURE WILL ENHANCE SNOWFALL ACROSS THE
REGION LATER THIS AFTERNOON INTO TONIGHT. TEMPERATURES AT THAT POINT
WILL BE COLD ENOUGH TO SUPPORT SNOW JUST ABOUT EVERYWHERE AND
FALLING SNOW WILL LIKELY CAUSE TRAVEL DISRUPTION THIS EVENING.

ONCE THE COASTAL DEVELOPS IT WILL INTENSIFY RAPIDLY AND PULL AWAY
FROM THE REGION TONIGHT. EARLIER INDICATION OF MORE SIGNIFICANT WRAP
AROUND SNOWFALL ALONG AND EAST OF THE I-95 CORRIDOR DOES NOT APPEAR
AS SIGNIFICANT. THREAT FOR WARNING LEVEL SNOW HAS DIMINISHED. HAVE
EXPANDED WINTER WEATHER ADVISORIES EAST THROUGH THE I-95 CORRIDOR
AND ALSO EXPANDED FURTHER SOUTH THROUGH 15Z TUESDAY. IMPACTS TO THIS
EVENING COMMUTE AND SOME INTO THE TUESDAY AM COMMUTE CAN BE
EXPECTED.

&&

.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
EARLY SNOW WILL PERSIST MAINLY ACROSS EASTERN SECTIONS AND SOME
UPSLOPE OVER THE POTOMAC HIGHLANDS. THE COASTAL LOW WILL PULL AWAY
TO THE NORTH AND SNOW WILL GRADUALLY END DURING THE DAY. COLD
TEMPERATURES WILL REMAIN IN PLACE WITH HIGHS ONLY REACHING THE 20S
OUT WEST WITH 30S EAST OF THE BLUE RIDGE. GUSTY NORTHWEST WINDS WILL
DROP WIND CHILLS INTO THE SINGLE DIGITS AND TEENS OUT WEST TO THE
LOWER 20S EAST. WINDS WILL GRADUALLY DIMINISH LATE IN THE DAY.

STRONG LOW PRESSURE OFF THE NEW ENGLAND COAST TUESDAY EVENING WILL
HEAD TOWARD NOVA SCOTIA TUESDAY NIGHT. HIGH PRESSURE WILL APPROACH
FROM THE OHIO VALLEY. A NORTHWEST FLOW BETWEEN THESE SYSTEMS WILL
USHER IN DRY AND COLD CONDITIONS FOR MOST AREAS. A FEW UPSLOPE
SNOW SHOWERS ARE POSSIBLE ALONG AND WEST OF THE ALLEGHENY
FRONT...BUT SNOW ACCUMULATION SHOULD BE LIGHT.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD OVERHEAD WEDNESDAY...BRINGING DRY AND
COLD CONDITIONS. A CLIPPER SYSTEM WILL PASS THROUGH THE AREA
THURSDAY INTO THURSDAY NIGHT. A PERIOD OF SNOW IS POSSIBLE WITH
THIS SYSTEM...ESPECIALLY ACROSS THE NORTHERN HALF OF THE CWA.

HIGH PRESSURE WILL RETURN FOR FRIDAY WITH DRY AND COLD CONDITIONS.
A STORM SYSTEM MAY IMPACT THE AREA NEXT WEEKEND. WINTRY
PRECIPITATION IS POSSIBLE. TIMING AND DETAILS ARE HIGHLY UNCERTAIN
AT THIS TIME.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
MVFR TO IFR TO PERSIST MUCH OF TODAY INTO TONIGHT WITH SNOW ACROSS
THE NORTHERN TIER AND RAIN MIXING WITH AND CHANGING TO SNOW FROM BWI
TO MTN TO IAD TO DCA THROUGH THE DAY. A STEADY LIGHT SNOW IS
EXPECTED LATER THIS AFTERNOON AND EVENING ACROSS THE TERMINALS WITH
TEMPERATURES AT OR BELOW FREEZING. THE SNOW WILL GRADUALLY END
OVERNIGHT OR TUESDAY AM.

NORTHWEST WINDS WILL CONTINUE TUESDAY NIGHT INTO WEDNESDAY WITH
GUSTS AROUND 20 TO 25 KNOTS. VFR CONDITIONS ARE EXPECTED DURING
THIS TIME. A CLIPPER SYSTEM MAY BRING A PERIOD OF SNOW TO THE
TERMINALS LATER THURSDAY INTO THURSDAY NIGHT...ESPECIALLY ACROSS
THE NORTHERN TERMINALS. HIGH PRESSURE WILL RETURN FRIDAY.

&&

.MARINE...
SCA CONDITIONS EXPECTED TO DEVELOP AS WINDS SHIFT INTO THE NORTH
THIS MORNING. WILL SEE INCREASING WINDS ON THE WATERS ALONG WITH
MIXED PRECIPITATION EVENTUALLY CHANGING TO SNOW LATER TODAY AND
TONIGHT. GALE CONDITIONS ARE EXPECTED LATER TONIGHT INTO TUESDAY AS
COASTAL LOW PRESSURE DEEPENS OFF THE MIDDLE ATLANTIC COAST. WINDS
WILL EVENTUALLY DIMINISH LATE TUESDAY OR EARLY WEDNESDAY.

GUSTY NORTHWEST WINDS ARE EXPECTED TUESDAY NIGHT THROUGH
WEDNESDAY. A SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED FOR THE
WATERS DURING THIS TIME. A GALE WARNING MAY BE NEEDED FOR PORTIONS
OF THE WATERS TUESDAY NIGHT. HIGH PRESSURE WILL BUILD OVERHEAD
WEDNESDAY NIGHT. A CLIPPER SYSTEM WILL PASS THROUGH THURSDAY
BEFORE HIGH PRESSURE RETURNS FRIDAY.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR DCZ001.
MD...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR MDZ004>006-
     011-013-014-503>508.
     WINTER STORM WARNING UNTIL 10 AM EST TUESDAY FOR MDZ003-501-
     502.
     WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM EST
     TUESDAY FOR MDZ016>018.
VA...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR VAZ025>027-
     029>031-039-040-051>054-501>508.
     WINTER STORM WARNING UNTIL 10 AM EST TUESDAY FOR VAZ028.
     WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 10 AM EST
     TUESDAY FOR VAZ037-038-050-055>057.
WV...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR WVZ505-506.
     WINTER STORM WARNING UNTIL 10 AM EST TUESDAY FOR WVZ050>053-
     055-501>504.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
     ANZ530>534-537>543.
     SMALL CRAFT ADVISORY FROM 6 AM TO 7 PM EST TUESDAY FOR
     ANZ530>534-537>543.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 AM EST TUESDAY FOR
     ANZ530>534-537>543.
     SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR ANZ535-536.

&&

$$
SYNOPSIS...BJL
NEAR TERM...KRW
SHORT TERM...BJL/KRW
LONG TERM...BJL
AVIATION...BJL/KLW
MARINE...BJL/KLW






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