539
FXUS61 KRLX 200604
AFDRLX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON WV
104 AM EST FRI DEC 20 2024
SYNOPSIS
WINTRY PRECIPITATION AND RAIN POSSIBLE FRIDAY, WITH
ACCUMULATING SNOW POSSIBLE FRIDAY NIGHT INTO SATURDAY. TURNING
DRY SUNDAY AND MONDAY. NEXT RAIN CHANCES ARRIVE TUESDAY.
NEAR TERM /THROUGH TODAY/
AS OF 100 AM FRIDAY...
INCREASED POPS ALONG THE MOUNTAINS FOR A FEW HOURS THIS MORNING
WITH MID-LEVEL WAVE APPROACHING AN INVERTED SURFACE TROUGH NEAR
THE MOUNTAINS. NOT SURE HOW MUCH PRECIPITATION THIS WILL BE ABLE
TO SQUEEZE OUT, BUT SHOULD BE FAIRLY SHORT LIVED.
AS OF 845 PM THURSDAY...
THE OVERNIGHT FORECAST REMAINS ON TRACK, BUT WITH SLIGHT UPWARD
ADJUSTMENTS TO SNOWFALL AMOUNTS, APPROACH OF THE START TIME OF
THE SNOW, AND IN COLLABORATION WITH NEIGHBORING OFFICES, ISSUED
A WINTER WEATHER ADVISORY FOR SNOW FOR THE MOUNTAINS, AND THE
THE SOUTHERN COAL FIELDS OF WV, FOR FRIDAY AFTERNOON INTO
SATURDAY. THIS IS THE RESULT OF A DIGGING MID/UPPER-LEVEL SHORT
WAVE TROUGH, AND A SURFACE LOW PRESSURE CENTER THAT FILLS AS IT
ENTERS THE FORECAST AREA FRIDAY AFTERNOON, IN FAVOR OF A NEW
SURFACE CENTER INTENSIFYING WELL OFFSHORE.
AS OF 700 PM THURSDAY...
THE FORECAST FOR THE OVERNIGHT IS ON TRACK, BUT ADJUSTMENTS TO
SNOW RATIOS FRIDAY NIGHT, AND PRECIPITATION AMOUNTS SUGGEST
SOMEWHAT HIGHER SNOW TOTALS FRIDAY INTO SATURDAY.
AS OF 130 PM THURSDAY...
HIGH PRESSURE CENTERED OVER THE DELMARVA REGION WILL ALLOW A
BRIEF PERIOD OF DRY WEATHER TO PROSPER INTO TONIGHT BEFORE THE
NEXT DISTURBANCE SAILS IN FOR THE END OF THE WORK WEEK. ORPHANED
MOISTURE FROM A PREVIOUS SYSTEM RETAINS RESIDENCY OVER THE AREA
THIS AFTERNOON, WITH VERY LIMITED SUNSHINE NOTED WITHIN OUR
FORECAST AREA AT THE TIME OF WRITING. CLOUDS ARE PROGGED TO
THICKEN ONCE MORE OVERNIGHT WITH THE ENCROACHING ARRIVAL OF OUR
NEXT WEATHER MAKER.
AN UPPER LEVEL TROUGH, COUPLED WITH AN ATTENDANT SURFACE LOW
PRESSURE SYSTEM, PIVOTS THROUGH THE OHIO VALLEY STARTING THIS
EVENING AND WILL ARRIVE ON OUR DOORSTEP DURING THE PREDAWN
HOURS FRIDAY MORNING. A WARM FRONT IS CURRENTLY ANALYZED TO BE
SPLITTING THROUGH KENTUCKY AND TENNESSEE, WITH THE EXPECTATION
THAT THIS WILL LIFT NORTHWARD OVERNIGHT AS THE PARENT LOW
MARCHES EASTWARD. THIS GIVES RISE TO ANOTHER BRIEF PERIOD OF
FREEZING RAIN EARLY FRIDAY MORNING ALONG THE HIGHER TERRAIN OUT
AHEAD OF THE MAIN SYSTEM, THEN CHANGING OVER TO A RAIN/SNOW
CONGLOMERATION AREAWIDE ON FRIDAY AS PRECIPITATION OVERTAKES THE
ENTIRETY OF THE FORECAST AREA.
HI-RES MODEL GUIDANCE DENOTES A DECENT BAND OF MOISTURE
DROPPING DOWN INTO AT LEAST THE SOUTHERN HALF OF THE CWA FRIDAY
AFTERNOON AND MEANDERING OVER THE AREA THROUGH THE EVENING IN
RESPONSE TO EMBEDDED SHORTWAVE ENERGY AND A PASSING COLD FRONT.
THIS LOOKS TO BE THE START OF WHEN WE'LL SEE ACCUMULATING
MOUNTAIN SNOW SHOWERS, WHICH THEN PROSPERS INTO THE SHORT TERM
FORECAST PERIOD. OUR MOUNTAIN ZONES COULD PICK UP A FEW TENTHS
TO AN INCH AND A HALF WITHIN THE FRIDAY AFTERNOON/EARLY EVENING
TIME SPAN. ELSEWHERE, WHILE POCKETS OF SNOW COULD BECOME
PROBABLE LATE IN THE PERIOD DOWN IN THE LOWLANDS AS SURFACE
TEMPERATURES LOWER WITH THE LOSS OF DAYTIME HEATING, THE PASSAGE
OF THE WARM FRONT WILL YIELD AFTERNOON HIGHS TO REACH THE MID
TO UPPER 40S, WHICH WILL KEEP THE PREDOMINANT PRECIP-TYPE AS
MOSTLY RAIN DURING THE DAY.
WITH THIS ISSUANCE, IT WAS ELECTED UPON BY COORDINATION WITH
NEIGHBORING OFFICES TO HOLD OFF ON ISSUING ANY WINTER HEADLINES
FOR FRIDAY/SATURDAY'S EVENT AND ALLOW FOR TIME TO SEE MODEL
EVOLUTION IN REGARDS TO SNOW ACCUMULATIONS. WILL HOIST UP A
SPECIAL WEATHER STATEMENT FOR NOW ALONG OUR MOUNTAIN ZONES FOR A
BRIEF PERIOD OF FREEZING RAIN FRIDAY MORNING. WHILE WE DON'T
HAVE MUCH IN THE WAY OF ACCUMULATING ICE WITH THE ONSET OF THIS
DISTURBANCE, THERE COULD BE A FEW ICY PATCHES THAT MAY ATTEMPT
TO FORM DURING THE FRIDAY MORNING COMMUTE WITHIN POCAHONTAS AND
RANDOLPH COUNTIES.
SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/
AS OF 132 PM THURSDAY...
UPSLOPE SNOW SHOWERS WILL CONTINUE INTO SATURDAY MORNING, MAINLY
ACROSS THE HIGHER ELEVATIONS. LOW-LEVEL MOISTURE WILL DISSIPATE BY
THE EARLY AFTERNOON, AND SNOW SHOWERS SHOULD COME TO AN END. A DEEP
UPPER-LEVEL TROUGH OVER THE NORTHEAST WILL KEEP A CHILLY FEEL IN THE
AIR THROUGHOUT THE WEEKEND, WITH HIGHS GENERALLY IN THE 20S AND 30S
SATURDAY AND SUNDAY. OVERNIGHT LOWS WILL BOTTOM OUT IN THE TEENS AND
LOWER 20S SATURDAY NIGHT AND SUNDAY NIGHT. AS SURFACE HIGH PRESSURE
EXPANDS OVER THE EASTERN U.S. SUNDAY, CLOUDS WILL CLEAR FOR
SUNSHINE.
LONG TERM /MONDAY THROUGH THURSDAY/
AS OF 133 PM THURSDAY...
HIGH PRESSURE WILL CONTINUE ITS INFLUENCE ON MONDAY, BRINGING QUIET
WEATHER AREAWIDE. MODELS SHOW A WEAK LOW PRESSURE SYSTEM APPROACHING
ON TUESDAY, CHRISTMAS EVE. THIS WOULD BRING RAIN SHOWERS TO MOST OF
THE LOWLANDS, WHILE THE MOUNTAINS SEE LIGHT SNOW SHOWERS TO START,
BUT EVENTUALLY TRANSITIONING TO RAIN SHOWERS AS WARM AIR SPILLS
NORTHWARD.
A STALLED FRONTAL BOUNDARY MAY BE DRAPED OVER OUR AREA FOR
WEDNESDAY, CHRISTMAS DAY. AT THIS TIME, TEMPERATURES LOOK FAIRLY
MILD WITH MODELS DEPICTING A WEAK MID-LEVEL RIDGE OVER THE OHIO
VALLEY. HIGHS ARE EXPECTED TO BE IN THE UPPER 40S TO LOWER 50S. ANY
PRECIPITATION ON CHRISTMAS DAY WOULD LIKELY BE IN THE FORM OF RAIN.
MODELS ARE STILL VERY INCONSISTENT REGARDING THE PLACEMENT AND
TIMING OF SURFACE AND UPPER-LEVEL FEATURES, SO FORECAST CONFIDENCE
IS LOW AT THIS TIME. AT THIS MOMENT, WE WILL GO WITH JUST A CHANCE
OF RAIN SHOWERS FOR THE MIDDLE OF NEXT WEEK. BEYOND WEDNESDAY,
THE FORECAST REMAINS UNCERTAIN, BUT WE BELIEVE THE MILD TREND
SHOULD CONTINUE.
AVIATION /06Z FRIDAY THROUGH TUESDAY/
AS OF 100 AM FRIDAY...
LARGELY MVFR CONDITIONS ARE EXPECTED THROUGH THIS MORNING WITH THE
EXCEPTION OF SOME LIGHT SNOW THAT COULD YIELD IFR CONDITIONS NEAR
THE NORTHEAST MOUNTAINS FROM AROUND 8 TO 12Z. ADDITIONAL
WIDEPSREAD PRECIPITATION ASSOCIATED WITH A QUICK HITTING
CLIPPER WILL CROSS FROM WEST TO EAST DURING THE LATE
MORNING/EARLY AFTERNOON - MAINLY RAIN OR A RAIN/SNOW MIX ACROSS
THE LOWER ELEVATIONS THROUGH THIS EVENING, THEN TRANSITIONING TO
FLURRIES TONIGHT. ACCUMULATING UPSLOPE ENHANCED SNOW SHOWERS
WILL LINGER IN THE MOUNTAINS WELL INTO SATURDAY.
WINDS LIGHT AND SOUTHERLY THIS MORNING, TRANSITIONING TO WESTERLY 5-
10KTS THIS AFTERNOON.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SATURDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: SNOW NEAR EKN THIS MORNING MAY NOT MAKE IT
TO THE TERMINAL. PRECIPITATION TYPE THIS AFTERNOON COULD VARY
BETWEEN RAIN, RAIN/SNOW MIX AND SNOW.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE FRI 12/20/24
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H H H H M H H H H H H H
HTS CONSISTENCY H H H H H M M M M H H M
BKW CONSISTENCY H H H M M H L H H H H H
EKN CONSISTENCY M H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H M H H H H H H H H H H
AFTER 06Z SATURDAY...
IFR POSSIBLE SNOW SHOWERS AND STRATUS SATURDAY MORNING.
RLX WATCHES/WARNINGS/ADVISORIES
WV...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM EST
SATURDAY FOR WVZ024>026-033-034-515-517-519.
WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 1 PM EST
SATURDAY FOR WVZ516-518-520>523-525-526.
OH...NONE.
KY...NONE.
VA...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 10 AM EST
SATURDAY FOR VAZ003-004.
SYNOPSIS...RPY/JMC
NEAR TERM...MEK/TRM/JP
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...JP
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