012
FXUS61 KLWX 151513
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1013 AM EST MON DEC 15 2025
SYNOPSIS
ARCTIC HIGH PRESSURE SETTLES OVER THE REGION THIS AFTERNOON
BEFORE SHIFTING OFFSHORE TUESDAY. THIS WILL YIELD A PATTERN
CHANGE WITH WARMING TEMPERATURES HEADING INTO THE MIDDLE OF THE
WEEK. A STRONG COLD FRONT WILL PUSH THROUGH LATE THURSDAY,
BRINGING THE NEXT CHANCE FOR PRECIPITATION. COOLER TEMPERATURES
RETURN FOR THE END OF THE WEEK.
NEAR TERM /THROUGH TONIGHT/
ARCTIC HIGH PRESSURE BUILDS OVERHEAD THIS AFTERNOON, RESULTING
IN TEMPERATURES NEARLY 15 DEGREES BELOW NORMAL. WINDS WILL
DIMINISH THIS AFTERNOON.
A PIECE OF SHORTWAVE ENERGY ON THE BACK SIDE OF THE PRIMARY
UPPER TROUGH THAT PUSHED THROUGH YESTERDAY WILL MOVE ACROSS THE
UPPER MID-ATLANTIC THIS AFTERNOON. SOME GUIDANCE TRIES TO BRING
OUT A FEW FLURRIES IN FAR NORTHERN MD, SO HAVE KEPT THOSE IN
THE FORECAST. HOWEVER, THE PROBABILITY IS VERY LOW, GIVEN THE
AMPLE DRY AIR WITH THE AFOREMENTIONED ARCTIC HIGH. SOME
INCREASING MID-LEVEL CLOUDS AT 10AM COULD BE A SIGN THAT
FLURRIES COULD TRY TO FALL, BUT NO GUARANTEE.
VERY COLD AGAIN TONIGHT AS HIGH PRESSURE SETTLES IN AND WINDS
BECOME LIGHT. SOME LOCATIONS COULD GET INTO THE SINGLE DIGITS.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/
PREVIOUS DISCUSSION...
ARCTIC HIGH PRESSURE SHIFTS EAST, AND AN UPPER RIDGE BUILDS
OVER THE REGION TUESDAY. THIS WILL RESULT IN SLIGHTLY WARMER
TEMPERATURES, BUT STILL REMAINING BELOW AVERAGE. SAME GOES FOR
TUESDAY NIGHT, WITH LOWS JUMPING BACK INTO THE MID TO UPPER 20S.
BY WEDNESDAY, IT WILL BE A GOOD BIT WARMER, WITH HIGHS ACTUALLY
JUMPING TO ABOVE NORMAL IN THE UPPER 40S TO MID 50S.
LONG TERM /THURSDAY THROUGH SUNDAY/
THE LONG TERM PERIOD WILL FEATURE A SYNOPTIC PATTERN CHARACTERIZED
BY FAST, QUASI-ZONAL FLOW ACROSS THE CONUS. EMBEDDED DISTURBANCES
WITHIN THE ZONAL FLOW WILL LEAD TO LARGE SWINGS IN TEMPERATURE
THROUGHOUT THE PERIOD.
HIGH PRESSURE WILL RETREAT OFFSHORE ON THURSDAY AS A POTENT
SHORTWAVE AND ASSOCIATED STRONG AREA OF LOW PRESSURE TRACK THROUGH
THE UPPER GREAT LAKES. SOUTHERLY FLOW WILL ADVECT MUCH WARMER AIR
INTO THE REGION, ALLOWING TEMPERATURES TO CLIMB INTO THE 50S. CLOUDS
WILL BE ON THE INCREASE, BUT MOST, IF NOT ALL OF THE DAY IS
EXPECTED TO REMAIN DRY. RAIN WILL MOVE IN OVERNIGHT AS THE UPPER
TROUGH RAPIDLY APPROACHES FROM THE WEST. A SOAKING, BUT BENEFICIAL
RAINFALL IS EXPECTED ACROSS THE ENTIRE AREA. A STRONG COLD FRONT
WILL MOVE THROUGH LATE THURSDAY NIGHT. THE RAIN COULD POTENTIALLY
END AS A BRIEF PERIOD OF UPSLOPE SNOW IN THE ALLEGHENIES LATE
THURSDAY NIGHT INTO FRIDAY MORNING.
MUCH COOLER AND WINDY CONDITIONS ARE EXPECTED BEHIND THE COLD FRONT
ON FRIDAY. DAYTIME HIGHS ARE EXPECTED TO RANGE FROM THE 20S IN THE
MOUNTAINS TO THE 40S ACROSS THE LOWER ELEVATIONS. GUSTY NORTHWEST
WINDS WILL MAKE IT FEEL MUCH COLDER, BUT CONDITIONS ARE EXPECTED TO
REMAIN DRY.
HIGH PRESSURE IS EXPECTED TO BUILD OVERHEAD FOR FRIDAY NIGHT INTO
SATURDAY. THIS WILL LEAD TO CONTINUED DRY CONDITIONS AND NEAR NORMAL
TEMPERATURES, WITH HIGHS IN THE 40S AND LOWS IN THE 20S. HIGH
PRESSURE WILL MOVE OFFSHORE ON SUNDAY, CAUSING SOUTHERLY FLOW TO
DEVELOP ONCE AGAIN. THIS WILL LEAD TO AN INCREASE IN TEMPERATURES,
WITH HIGHS IN THE UPPER 40S TO 50S FOR MOST. ANOTHER FAST MOVING
DISTURBANCE MAY PASS OFF TO OUR NORTH THROUGH THE GREAT LAKES.
DEPENDING ON HOW THIS SYSTEM TRACKS, SOME SHOWERS MAY BE POSSIBLE ON
SUNDAY.
AVIATION /15Z MONDAY THROUGH FRIDAY/
WINDS WILL DIMINISH THIS AFTERNOON. LIGHT WINDS EXPECTED MONDAY
NIGHT AND TUESDAY WITH WINDS SHIFTING TO THE SOUTHWEST AND THEN
SOUTH.
VFR CONDITIONS ARE EXPECTED WEDNESDAY AS HIGH PRESSURE SHIFTS
OFFSHORE.
SUB-VFR CONDITIONS APPEAR LIKELY THURSDAY INTO THURSDAY NIGHT IN
ASSOCIATION WITH LOW CEILINGS AND RAIN. GUSTY SOUTHERLY WINDS DEVELOP
THURSDAY AFTERNOON AND EVENING AHEAD OF A STRONG COLD FRONT THURSDAY
NIGHT INTO FRIDAY. SUB-VFR CONDITIONS CAN BE EXPECTED LATE
THURSDAY INTO FRIDAY WITH RAIN ASSOCIATED WITH THE FRONT.
VFR CONDITIONS AND GUSTY NORTHWESTERLY WINDS ARE EXPECTED ON
FRIDAY IN THE WAKE OF THE COLD FRONT.
MARINE
SCA CONDITIONS WILL CONTINUE FOR ANOTHER FEW HOURS BEFORE WINDS
DIMINISH ENOUGH WITH HIGH PRESSURE FOR THE SCA TO EXPIRE.
AS THE HIGH PASSES TO THE SOUTHEAST, SCAS MAY BE NEEDED FOR
PARTS OF THE WATERS TONIGHT IN SOUTH TO SOUTHWEST FLOW.
AFTER DECREASING TUESDAY, SCA CONDITIONS ARE POSSIBLE AGAIN
TUESDAY 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 AS SOUTH/SOUTHEASTERLY FLOW
INCREASES.
AT LEAST SMALL CRAFT ADVISORY GUSTS APPEAR LIKELY IN SOUTHERLY FLOW
ON THURSDAY, AND THEN NORTHWESTERLY FLOW ON FRIDAY. DEPENDING ON THE
ULTIMATE STRENGTH OF THE SYSTEM, A FEW GALE GUSTS CAN'T BE RULED OUT
EITHER DAY.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...LOW WATER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR MDZ008.
SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR MDZ008.
VA...NONE.
WV...NONE.
MARINE...LOW WATER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
ANZ530>532-535-536-538>540.
SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
ANZ530>543.
SYNOPSIS...LFR
NEAR TERM...KLW/CJL
SHORT TERM...CJL
LONG TERM...KJP
AVIATION...KLW/CJL/KJP
MARINE...KLW/CJL/KJP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page