306
FXUS62 KRAH 240901 CCA
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
400 AM EST WED DEC 24 2025
SYNOPSIS
A COLD FRONT WILL MOVE SOUTH AND ACROSS THE CAROLINAS TODAY, THEN
STALL NEAR THE SAVANNAH BASIN TONIGHT, WHEN HIGH PRESSURE WILL
MIGRATE ACROSS THE MIDDLE ATLANTIC. THE FRONT WILL RETURN NORTH
ACROSS THE CAROLINAS AS A WARM FRONT CHRISTMAS DAY, ONLY TO MOVE
SOUTH AS A COLD FRONT AGAIN THURSDAY NIGHT. COLD HIGH PRESSURE WILL
FOLLOW AND RIDGE ACROSS THE MIDDLE ATLANTIC ON FRIDAY.
NEAR TERM /THROUGH TONIGHT/
AS OF 340 AM WEDNESDAY...
* AN UNSEASONABLY MILD CHRISTMAS EVE, WITH PATCHY LIGHT RAIN
POSSIBLE OVER W-CNTL NC THU MORNING
A 590 DAM SUB-TROPICAL HIGH AT 500 MB, EXTENDING ACROSS THE UPR TX
COAST AND NWRN GULF, WILL REMAIN. A RIDGE EXTENDING FROM THE HIGH
AND NWD ACROSS THE PLAINS --ONE THAT BROKE MONTHLY RECORD 500 MB
HEIGHTS ACROSS SEVERAL UPR AIR SITES OVER THE CNTL PLAINS AND MID MS
VALLEY ON TUE, AND WITH UNDERLYING RECORD WARMTH AT THE SURFACE--
WILL BE BRIEFLY DAMPENED BY A SHORTWAVE PERTURBATION THAT WILL
PROGRESS AROUND IT AND INTO THE SRN MIDDLE ATLANTIC BY 12Z THU.
ACCOMPANYING AND SLIGHTLY PRECEDING THAT SHORTWAVE PERTURBATION, A
ZONE OF RELATIVELY STRONG AND DEEP LWR/MID-LEVEL WAA WILL PROGRESS
ACROSS THE APPALACHIANS LATE TONIGHT-THU MORNING. THE MODELS DEPICT
A RELATIVE MAXIMUM OF THIS WAA OVER W-CNTL NC AND SRN VA AT 925 MB
AROUND 12Z THU.
AT THE SURFACE, THE FRONTAL ZONE THAT RETREATED NWD AND ACROSS CNTL
NC ON TUE, NOW LOCATED OVER E-CNTL VA AND WHICH SEPARATED AT 08Z 30S
FROM THE ERN PART OF THE COMMONWEALTH FROM RATHER REMARKABLE LWR 60S
(~30 F ABOVE AVERAGE) AT ROA AND CHO, WILL RETURN SWD AND ACROSS
CNTL NC AS A BACKDOOR COLD FRONT TODAY. THE FRONT WILL STALL NEAR
AND PROBABLY JUST NORTHEAST OF THE SAVANNAH BASIN TONIGHT. FOLLOWING
AND FORCING THAT FRONT SWWD, ~1025 MB HIGH PRESSURE NOW OVER OH/IN
WILL MIGRATE QUICKLY SEWD AND ACROSS AND OFFSHORE THE SRN MIDDLE
ATLANTIC THROUGH 12Z THU.
DESPITE THE PROGRESSION OF THE BACKDOOR FRONT ACROSS CNTL NC TODAY,
TEMPERATURES WILL REMAIN MILD GIVEN MORE DRY AIR ADVECTION THAN COLD
BEHIND IT, NNWLY DOWNSLOPE FLOW THAT WILL WEAKEN FROM ~40 KTS THIS
MORNING TO 15-20 KTS BY SUNSET, AND MOSTLY SUNNY SKIES THAT WILL BE
INTERRUPTED BY A SHORT PERIOD OF OROGRAPHIC CIRRUS OVER THE WRN
PIEDMONT THIS MORNING AND ANOTHER PLUME OF HIGH-LEVEL MOISTURE
AROUND SUNSET. TEMPERATURES WILL CONSEQUENTLY BE WELL ABOVE AVERAGE
AND RANGE FROM MID-UPR 60S ACROSS THE NRN PIEDMONT AND COASTAL PLAIN
TO LWR 70S ELSEWHERE. LOW TEMPERATURES TONIGHT WILL RANGE FROM
MID/UPR 30S IN THE NRN COASTAL PLAIN AND NE PIEDMONT TO MID/UPR 40S
OVER THE SRN AND WRN PIEDMONT, WITH THE LATTER REGULATED BY MVFR
RANGE CEILINGS AND AN ASSOCIATED CHANCE OF PATCHY, LIGHT RAIN THAT
WILL PROGRESS WITH THE AFOREMENTIONED 925 MB WAA REGIME ACROSS W-
CNTL NC AFTER 06Z.
SHORT TERM /THURSDAY AND THURSDAY NIGHT/
AS OF 400 AM WEDNESDAY...
* CONTINUED UNSEASONABLY MILD ON CHRISTMAS, BUT WITH WARMING SLOWED
THROUGH THE MORNING BY MULTI-LAYERED CEILINGS AND PATCHY LIGHT
RAIN THAT WILL PROGRESS EWD AND OUT OF CNTL NC THROUGH THE
AFTERNOON
A SHORTWAVE PERTURBATION IN NWLY FLOW ALOFT, AND PRECEDING LOW/MID-
LEVEL WAA REGIME, WILL PROGRESS ACROSS AND OFFSHORE THE SRN MIDDLE
ATLANTIC EARLY THU. A SUB-TROPICAL HIGH OVER THE GULF, AND RIDGE
INITIALLY EXTENDING ACROSS THE PLAINS AND MS VALLEY, WILL OTHERWISE
BREAK DOWN AND YIELD INCREASINGLY-ZONAL FLOW ACROSS THE MID-
LATITUDES BY THU NIGHT.
AT THE SURFACE, THE WAVERING FRONTAL ZONE THAT WILL HAVE SETTLED TO
NEAR AND NORTHEAST OF THE SAVANNAH BASIN WED NIGHT WILL RETREAT NEWD
AND ACROSS THE CAROLINAS AS A WARM FRONT CHRISTMAS DAY, ONLY TO MOVE
SOUTH AS A COLD FRONT AGAIN THURSDAY NIGHT. COLD HIGH PRESSURE WILL
FOLLOW AND RIDGE ACROSS THE MIDDLE ATLANTIC THU NIGHT-FRIDAY.
MULTI-LAYERED CEILINGS AND PATCHY LIGHT RAIN/SPRINKLES, ACCOMPANYING
THE AFOREMENTIONED LOW/MID-LEVEL WAA REGIME, WILL PROGRESS EWD AND
OUT OF CNTL NC THROUGH EARLY AFTERNOON. ASSOCIATED CLEARING, AND
DEEPENING OF THE BOUNDARY LAYER/MIXING, WILL CAUSE SWLY SURFACE
WINDS TO STRENGTHEN AND GUST UP TO 20-25 MPH DURING THE AFTERNOON,
WITH NEARLY PERSISTENCE HIGH TEMPERATURES RANGING FROM UPR 60S NE TO
LWR-MID 70S SW. LOW TEMPERATURES WILL BE EQUALLY PERSISTENCE IN THE
UPR 30S NE TO MID/UPR 40S SW, WITH A SHORT PERIOD OF NELY GUSTINESS
IN CAA BEHIND THE BACKDOOR FRONT OVERNIGHT, ALONG WITH AREAS OF POST-
FRONTAL LOW OVERCAST.
LONG TERM /FRIDAY THROUGH WEDNESDAY/
AS OF 139 AM WEDNESDAY...
UPPER PATTERN: AN ANOMALOUS RIDGE WILL DE-AMPLIFY LATE THURSDAY AS A
SHORT-WAVE MOVES EAST ACROSS THE OHIO VALLEY FRIDAY INTO SATURDAY.
THE RIDGE WILL BRIEFLY RE-ESTABLISH ITSELF OVER THE DEEP SOUTH ON
SATURDAY AHEAD OF A DEEPER TROUGH WILL DIG DOWN FROM CANADA AND MOVE
ACROSS THE EASTERN US LATE SUNDAY INTO TUESDAY. NWLY FLOW AND RISING
MID-LEVEL HEIGHTS ALOFT WILL SPREAD EAST ACROSS CENTRAL NC
WEDNESDAY.
FRIDAY: GUIDANCE CONTINUES TO TREND COLDER WITH A POTENTIAL SHORT-
LIVED WEDGE AND ASSOCIATED NELY FLOW ON FRIDAY. RAIN CHANCES ARE
LIMITED AS THE MAIN FORCING AND ANOMALOUS MOISTURE WILL REMAIN NORTH
OF US, BUT AREAS ALONG THE NC/VA BORDER MAY SEE SOME LIGHT RAIN
FRIDAY. REGARDLESS, PERSISTENT NELY FLOW AND CLOUD COVER WILL KEEP
TEMPS DOWN IN THE LOWER 40S (NE) TO MID 50S (SW). ANY LINGERING RAIN
SHOULD ERODE AND EXIT TO OUR EAST FRIDAY NIGHT AS SLY FLOW RE-
ESTABLISHES OVER OUR AREA. OVERNIGHT LOWS IN THE MID 40S ARE
EXPECTED FRIDAY NIGHT.
SATURDAY THROUGH WEDNESDAY: AFTER A DRY AND WARMER SATURDAY (HIGHS
IN THE UPPER 60S TO LOWER 70S), A MORE AMPLIFIED SYSTEM WILL PUSH
ACROSS THE EASTERN US SUNDAY INTO EARLY NEXT WEEK. GUIDANCE HAS
TRENDED SLOWER WITH THE ARRIVAL OF A STRONG COLD FRONT AND
ASSOCIATED CAA. MOST GUIDANCE NOW HAS THE FRONT MOVING ACROSS
CENTRAL NC EARLY MONDAY, WITH CAA RAMPING UP LATER DURING THE DAY.
AS SUCH, HIGHS ON MONDAY WILL LIKELY BY HIGHER THAN PREVIOUSLY
THOUGHT, REACHING THE UPPER 40S TO MID 50S. STILL EXPECTING SOME
STRONGER POST-FRONTAL NWLY GUSTS OF 20 TO 30 MPH MONDAY AFTERNOON
INTO THE EARLY OVERNIGHT PERIOD MONDAY NIGHT. TEMPS WILL DROP INTO
THE LOWER TO MID 20S EARLY TUESDAY MORNING. HIGHS ON TUESDAY WILL
STRUGGLE TO REACH THE UPPER 30S WHILE OVERNIGHT LOWS DROP INTO THE
MID TO UPPER TEENS.
RAIN CHANCES WILL PEAK SUNDAY NIGHT INTO MONDAY MORNING WITH THE
FRONTAL PASSAGE. OVERALL THOUGH ENSEMBLES CONTINUE TO HIGHLIGHT LOW
QPF WITH THIS SYSTEM (95TH PERCENTILES AMONGST ENSEMBLES PEAK AROUND
A FEW HUNDREDS TO A FEW TENTHS OF AN INCH OF RAIN).
LOW-LEVEL THICKNESSES REMAIN LOWER THROUGH THE END OF THE WEEK WITH
A POTENTIALLY RE-ENFORCING COLD FRONT THURSDAY INTO FRIDAY. AS SUCH,
CURRENT SIGNS SHOW THE POTENTIAL FOR A CHILLY START TO THE NEW YEAR.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
AS OF 120 AM WEDNESDAY...
VFR, AND MAINLY CLEAR, EXCEPT WITH PERIODS OF CIRRUS AND
CIRROSTRATUS. A DRY COLD FRONT WILL MOVE SOUTH ACROSS CNTL NC THIS
MORNING AND CAUSE INITIALLY LIGHT WSWLY SURFACE WINDS TO VEER TO NLY
AND STRENGTHEN/BRIEFLY GUST INTO THE TEENS KTS (TO AROUND 20 KTS AT
GSO/INT) THROUGH EARLY THIS AFTERNOON.
OUTLOOK: A LINGERING FRONTAL ZONE TO OUR SOUTH LATE WEDNESDAY WILL
WAVER NORTH AT TIMES THROUGH THE WEEKEND RESULTING IN MULTIPLE
PERIODS WITH A RISK OF ADVERSE AVIATION CONDITIONS. AREAS OF MVFR
CIGS ARE POSSIBLE ON THURSDAY MORNING ACROSS THE WESTERN PIEDMONT,
WITH A GREAT RISK OF MVFR TO IFR CIGS ACROSS THE AREA ON FRIDAY AND
FRIDAY NIGHT WITH ANOTHER CHANCE LATE SUNDAY AS A STRONG COLD FRONT
MOVES ACROSS THE AREA. -BLAES
RAH WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...LUCHETTI
AVIATION...MWS/BLAES
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