004
FXUS61 KLWX 150240
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
940 PM EST SUN DEC 14 2025
SYNOPSIS
BITTERLY COLD CONDITIONS ARE EXPECTED TONIGHT AS ARCTIC HIGH
PRESSURE BUILDS INTO THE REGION. WIND CHILLS WILL FALL INTO THE
SINGLE DIGITS FOR MOST LOCATIONS HEADING INTO MONDAY MORNING
WITH SUBZERO VALUES OVER THE MOUNTAINS. COLD CONDITIONS
CONTINUE THROUGH MONDAY NIGHT WITH GRADUALLY WARMING
TEMPERATURES TUESDAY AND WEDNESDAY. RAIN CHANCES RETURN WITH A
STRONG COLD FRONT LATE WEEK.
NEAR TERM /UNTIL 6 AM MONDAY MORNING/
PRIMARY UPPER TROUGH AXIS IS SWINGING EAST FROM THE EASTERN PART
OF THE CWA THIS EVENING. WITH DECREASING LIFT AND INCREASING
SUBSIDENCE, ALLEGHENY SNOW SHOWERS HAVE BEEN DECREASING IN
INTENSITY. HOWEVER, THERE ARE STILL SOME MOISTURE STREAMERS OFF
THE GREAT LAKES, AND THESE COULD PRODUCE SOME BRIEFLY HEAVIER
SNOW IF THEY INTERSECT THE TERRAIN. GIVEN THE COLD THERMAL
PROFILES, SOME SPOTS COULD PICK UP ANOTHER INCH OVERNIGHT, BUT
THIS WAS NOT ENOUGH TO WARRANT EXTENDING THE WINTER HEADLINES.
THE 850 MB TEMPERATURE ON THE 00Z IAD SOUNDING WAS -20C, WHICH
RANKS AMONGST THE COLDEST TEMPERATURES AT THAT LEVEL THIS EARLY
IN THE SEASON. PLUMMETING SURFACE TEMPERATURES AND ELEVATED
WINDS HAVE BEEN RESULTING IN LOCALIZED WIND CHILL VALUES A
LITTLE LOWER THAN FORECAST, GENERALLY BETWEEN -5 AND +5F IN THE
LOWER ELEVATIONS, -10 TO -20F ON THE RIDGES, AND A FEW OBS OF
-20 TO -30 ON EXPOSED RIDGES ABOVE 4000 FT. COVERED THIS FACT
WITH AN SPS WHERE THE ADVISORY IS NOT IN EFFECT SINCE THESE
VALUES APPROACH ADVISORY CRITERIA. WHILE WINDS WILL BE
DECREASING THE SECOND HALF OF THE NIGHT, EXTENDED THE EARLIER
COLD ADVISORY EXPIRATION TIMES UNTIL 7 AM SINCE THE UPDATED
FORECAST SUPPORTED IT.
ANY RESIDUAL SNOW MELT (OR SNOW BLOWN BACK ONTO ROADS) IS
LIKELY FREEZING SOLID ON UNTREATED SURFACES GIVEN WIDESPREAD
TEMPERATURES IN THE TEENS. AIR TEMPERATURES MAY DROP SEVERAL
MORE DEGREES FROM WHERE THEY ARE NOW, BUT THE COLD ADVECTION
(WHICH WILL NEUTRALIZE THE SECOND HALF OF THE NIGHT) HAS ALREADY
TAKEN THE TEMPERATURES CLOSE TO THE EXPECTED OVERNIGHT LOWS.
SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/
FOR THE PAST COUPLE OF DAYS, MODELS HAVE BEEN TRYING TO DEVELOP
AN AREA OF VERY LIGHT SNOW ACROSS NORTHERN MD MONDAY AFTERNOON
AS SHORTWAVE ENERGY DROPS SOUTHEASTWARD FROM LK HURON. CLOSE
EXAMINATIONS OF MODEL SOUNDINGS SHOW VERY DRY AIR/LARGE DEWPOINT
DEPRESSIONS BELOW 700 MB ACROSS NORTHERN MD AND SOUTHERN PA.
VERY DOUBTFUL THAT ANYTHING WOULD BE ABLE TO REACH THE GROUND.
VERY COLD MONDAY NIGHT AS HIGH PRESSURE SETTLES IN AND WINDS
BECOME LIGHT. SLOW WARMING TREND BEGINS TUESDAY AS HIGH PRESSURE
SHIFTS OFFSHORE AND WINDS TURN MORE SOUTHERLY WITH TIME.
LONG TERM /WEDNESDAY THROUGH SUNDAY/
TEMPERATURES CONTINUE TO WARM MIDWEEK AS A RESULT OF HIGH PRESSURE
WEAKENING AND PUSHING FURTHER OFF THE EAST COAST. ZONAL FLOW WILL
PREVAIL ALOFT WITH WARM AIR ADVECTION ENSUING OUT OF THE SOUTHWEST
AT THE SURFACE. THIS WILL HELP TEMPERATURES REBOUND BACK TO NORMAL
LEVELS IF NOT ABOVE NORMAL ON BOTH WEDNESDAY AND THURSDAY AFTERNOON.
HIGH TEMPERATURES WEDNESDAY WILL PUSH INTO THE MID TO UPPER 40S WITH
PORTIONS OF THE SHENANDOAH VALLEY AND CENTRAL VA PIEDMONT
REACHING INTO THE MID 50S. MOUNTAIN LOCATIONS WILL THAW OUT AS
WELL WITH HIGHS IN THE UPPER 30S. LOWS WEDNESDAY NIGHT WILL FALL
BACK INTO THE UPPER 20S AND LOW 30S.
DRY CONDITIONS WILL LIKELY PREVAIL THROUGH THURSDAY AFTERNOON WITH
INCREASING CLOUDS AS A POTENT TROUGH AND SURFACE LOW PRESSURE SYSTEM
WORK INTO THE GREAT LAKES REGION. THIS LOW PRESSURE SYSTEM WILL SEND
A SERIES OF WEAK WARM FRONTAL BOUNDARIES THROUGH THE REGION THURSDAY
AFTERNOON AND EVENING WITH A POTENT COLD FRONT SET TO CROSS LATE
THURSDAY NIGHT INTO FRIDAY. TEMPERATURES THURSDAY WILL WARM INTO THE
LOW TO MID 50S WITH UPPER 40S IN THE MOUNTAINS.
WITH THE SERIES OF FRONTS PASSING THROUGH EXPECT INCREASED CLOUD
COVER THROUGHOUT THE DAY AND PERHAPS A SPOTTY SHOWER DURING THE
AFTERNOON. ANY SUBSTANTIAL RAIN AND/OR CONVECTION LOOKS TO HOLD OFF
UNTIL THURSDAY NIGHT INTO EARLY FRIDAY MORNING. SEVERE WEATHER DOES
NOT APPEAR TO BE CONCERN AT THIS TIME, BUT GIVEN THE STRONG WIND
FIELDS ALOFT AND STRONG WARM AIR ADVECTION AT THE SURFACE,
CONVECTIVE ELEMENTS CANNOT BE RULED OUT. AS IT STANDS NOW, THE
HIGHEST WINDS LOOK TO BE CONFINED TO THE MOUNTAINS WITH LOWER GUSTS
OVER THE LOWER ELEVATIONS. RAIN WILL CHANGE TO SNOW OVER THE
MOUNTAINS FRIDAY MORNING WITH UPSLOPE SNOW SHOWERS LINGERING INTO
FRIDAY NIGHT. THIS IS CONCURRENT WITH 12Z ENSEMBLE/DETERMINISTIC
GUIDANCE WHICH CONTINUES TO SHOW OVERLAP ON THE LATE THURSDAY
EVENING INTO EARLY FRIDAY MORNING TIMEFRAME FOR HAZARDOUS WEATHER
CONCERNS.
HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY INTO SATURDAY.
WHILE COOLER, A ZONAL FLOW PATTERN ALOFT WILL REMAIN RESULTING IN
NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES. THE FORECAST HAS A SMALL
CHANCE OF RAIN/SNOW IN THE ALLEGHENIES SATURDAY WITH SOME POTENTIAL
FOR EMBEDDED WEAK SHORTWAVES IN THE ZONAL FLOW TO ROUND OUT THE
WEEKEND.
AVIATION /02Z MONDAY THROUGH FRIDAY/
SOME REMAINING NW WIND GUSTS UP TO 30 KT WILL CONTINUE THROUGH
THIS EVENING BEFORE DIMINISHING TO 25 KT LATE AND BELOW 15 KT
MONDAY BY MONDAY AFTERNOON. BRIEF BKN CIGS AROUND FL045 REMAIN
POSSIBLE AT MRB UNTIL THE SECOND HALF OF THE NIGHT. LIGHT WINDS
MONDAY NIGHT AND TUESDAY WITH WINDS SHIFTING TO SW AND THEN S.
VFR CONDITIONS ARE EXPECTED WEDNESDAY THROUGH THURSDAY AFTERNOON AS
HIGH PRESSURE SHIFTS OFFSHORE. GUSTY SOUTHERLY WINDS DEVELOP
THURSDAY AFTERNOON AND EVENING AHEAD OF A STRONG COLD FRONT THURSDAY
NIGHT INTO FRIDAY. SUB-VFR CONDITIONS WILL RETURN WITH THE FRONT
THURSDAY NIGHT INTO FRIDAY AS A LINE OF SHOWERS AND PERHAPS AN
EMBEDDED THUNDERSTORM PUSH THROUGH. VFR CONDITIONS RETURN FOR THE
WEEKEND AHEAD.
MARINE
GALE CONDITIONS IN NW FLOW CONTINUE THIS EVENING BUT WILL
GRADUALLY SCALE BACK AS THE NIGHT PROGRESSES. SCA CONDITIONS
WILL CONTINUE UNTIL EARLY AFTERNOON MONDAY BEFORE DECREASING AS
HIGH PRESSURE PASSES. THE STRONG NORTHWEST WINDS ARE ALSO
CREATING LOW WATER LEVELS, ESPECIALLY AT LOW TIDE, SO A LOW
WATER ADVISORY IS IN EFFECT THROUGH PARTS OF MONDAY. AS THE HIGH
PASSES TO THE SOUTHEAST, SCAS MAY BE NEEDED FOR PARTS OF THE
WATERS MONDAY NIGHT IN SOUTH TO SOUTHWEST FLOW. AFTER DECREASING
TUESDAY, SCA CONDITIONS ARE POSSIBLE AGAIN TUE NIGHT IN
SOUTHERLY CHANNELING.
ANY RESIDUAL SOUTHERLY CHANNELING SHOULD COME TO AN END WEDNESDAY
MORNING INTO WEDNESDAY AFTERNOON. SUB-SCA LEVEL WINDS RETURN
WEDNESDAY AFTERNOON AND EVENING WITH HIGH PRESSURE NEARBY. SCAS
RETURN LATE WEDNESDAY NIGHT THROUGH THURSDAY NIGHT AS
SOUTH/SOUTHEASTERLY FLOW INCREASES. THIS IS IN ASSOCIATION WITH A
POTENT LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT PUSHING IN FROM
THE OHIO RIVER VALLEY. THE COLD FRONT WILL CROSS THURSDAY NIGHT
BRINGING A BRIEF PERIOD OF GALE CONDITIONS. ADDITIONAL SCAS WILL BE
NEEDED FRIDAY WITH HIGH PRESSURE RETURNING THIS WEEKEND.
TIDES/COASTAL FLOODING
LOW WATER ADVISORIES HAVE BEEN ISSUED FOR ALL WATER, WITH
MINIMUM TIDES EXPECTED LATE TONIGHT INTO MONDAY MORNING. WATER
LEVELS MAY RECOVER QUICKLY LATE MONDAY AS WINDS SWITCH TO THE
SOUTHWEST.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...GALE WARNING UNTIL 11 PM EST THIS EVENING FOR MDZ008.
LOW WATER ADVISORY UNTIL 3 PM EST MONDAY FOR MDZ008.
SMALL CRAFT ADVISORY UNTIL 1 PM EST MONDAY FOR MDZ008.
COLD WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR MDZ501.
COLD WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR MDZ509-510.
VA...COLD WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR VAZ025-026-504-
507-508.
COLD WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR VAZ503.
WV...COLD WEATHER ADVISORY UNTIL 7 AM EST MONDAY FOR WVZ503-506.
COLD WEATHER ADVISORY UNTIL 10 AM EST MONDAY FOR WVZ501-505.
MARINE...GALE WARNING UNTIL 11 PM EST THIS EVENING FOR ANZ530-531-535-
536-538-539.
LOW WATER ADVISORY UNTIL 3 PM EST MONDAY FOR ANZ530>532-535-
536-538>540.
SMALL CRAFT ADVISORY UNTIL 1 PM EST MONDAY FOR ANZ530-531-535-
536-538-539.
GALE WARNING UNTIL 6 AM EST MONDAY FOR ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EST MONDAY FOR
ANZ532>534-537-540>543.
LOW WATER ADVISORY UNTIL 10 AM EST MONDAY FOR ANZ533-534-537-
541>543.
SYNOPSIS...LFR
NEAR TERM...ADS
SHORT TERM...LFR
LONG TERM...EST
AVIATION...ADS/LFR/EST
MARINE...ADS/LFR/EST
TIDES/COASTAL FLOODING...ADS
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