085
FXUS63 KLMK 222021
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
321 PM EST MON DEC 22 2025
KEY MESSAGES
* MILDER TEMPERATURES AND INTERMITTENT LIGHT RAIN CHANCES ARE
EXPECTED DURING MUCH OF THE UPCOMING WEEK.
* UNSEASONABLY WARM TEMPERATURES ARE LIKELY AROUND CHRISTMAS, WITH
TEMPERATURES EXPECTED TO BE 15-20 DEGREES ABOVE NORMAL.
* MILD WEATHER CONTINUES INTO THE FIRST PART OF THE WEEKEND, BUT
WILL GRADUALLY TREND COOLER BY SUNDAY WITH A SERIES OF REINFORCING
COLD FRONTS. THERE IS LOW, BUT INCREASING POTENTIAL FOR A STRONGER
SYSTEM SATURDAY NIGHT INTO SUNDAY THAT COULD BRING STRONG TO
SEVERE STORMS.
SHORT TERM /THROUGH TUESDAY/
ISSUED AT 320 PM EST MON DEC 22 2025
CLOUDS HAVE BUILT BACK ACROSS THE REGION THIS AFTERNOON, BUT WE HAVE
MANAGED TO WARM INTO THE UPPER 40S AND LOW 50S THANKS TO A WARM AIR
ADVECTION REGIME. REGIONAL VAD WIND PROFILES, COMBINED WITH SPC
MESOANALYSIS, SHOW THERE BEING A SOUTHWESTERLY 35KT LLJ IN THE 850MB
LAYER, WHICH IS LOCATED IN THE VICINITY OF A SUBTLE SFC BOUNDARY.
SFC HIGH PRESSURE OVER CHESAPEAKE BAY TODAY ALSO ADDS TO THE WARM
RETURN FLOW.
LOW LEVEL MOISTURE TRANSPORT IS JUST NOW STARTING TO CREEP INTO
SOUTHERN KY, AND EXPECT THAT TO CONTINUE TO STRENGTHEN OVER THE NEXT
6-12 HOURS AS THE LLJ CONTINUES TO STRENGTHEN AND ISENTROPIC UPGLIDE
INCREASES. BY 06Z TONIGHT, THE LLJ IS EXPECTED TO BE AROUND 45KTS IN
THE 850MB LAYER, WITH OUR MOISTURE TRANSPORT VECTORS MAXIMIZED. THIS
WILL LEAD TO OUR PWATS TO RAMP UP TO AROUND 0.9-1.0" OVERNIGHT, PER
THE HREF ENSEMBLE MEAN, AND SUPPORTIVE FOR SCATTERED GUSTY LIGHT
RAIN SHOWERS ACROSS THE ENTIRE FORECAST AREA TONIGHT. POPS PEAK
BETWEEN 00Z AND 12Z, BUT THIS ROUND OF RAIN IS ONE OF THOSE
SCENARIOS THAT FEATURE HIGH POPS BUT LOW QPF.
LIGHT RAIN LOOKS TO LINGER INTO TOMORROW MORNING FOR AT LEAST SOME
OF THE FORECAST AREA AS THE LLJ GRADUALLY SHIFTS EAST. WITH
UNIMPRESSIVE MOISTURE IN THE MID-LEVELS, TOTAL PRECIP AMOUNTS AROUND
OR LESS THAN A TENTH OR TWO IS EXPECTED THROUGH TOMORROW MORNING.
LINGERING LOW-LEVEL MOISTURE TRAPPED UNDERNEATH AN INVERSION THROUGH
TOMORROW, WITH MODEL SOUNDINGS INDICATING SOME DRIZZLE POSSIBLE.
WITH BREEZY SOUTHERLY WINDS THROUGH THE NIGHT, WAA REMAINS IN PLACE,
WITH TEMPS ONLY GETTING DOWN INTO THE MID-40S TO NEAR 50. TEMPS FOR
TOMORROW PEAK AROUND 60.
LONG TERM /TUESDAY NIGHT THROUGH MONDAY/
ISSUED AT 320 PM EST MON DEC 22 2025
===== CHRISTMAS EVE THROUGH CHRISTMAS DAY =====
LOW OVERCAST CLOUDS AND A FEW ISOLATED LIGHT SHOWERS WILL BE
POSSIBLE WEDNESDAY MORNING AS THE SFC BOUNDARY WILL BE SITUATED
ACROSS THE AREA. HOWEVER, MOST OF THE REGION SHOULD REMAIN MOSTLY
DRY THROUGH THE DAY AS MID-LEVEL RIDGING BUILDS AND MOISTURE DOES
NOT APPEAR TO BE VERY DEEP. TEMPS WILL BE WELL ABOVE NORMAL FOR
CHRISTMAS EVE, WITH FORECAST HIGHS IN THE LOWER TO MID-60S.
A SUBTLE SHORTWAVE EMBEDDED WITHIN THE PROGRESSIVE NW FLOW LOOKS TO
BRING A SFC LOW THROUGH THE GREAT LAKES WEDNESDAY NIGHT, LIFTING THE
WARM FRONT THROUGH MOST OF THE FORECAST AREA BY THURSDAY MORNING.
WE'LL SEE AN INCREASE IN OUR POPS FOR CHRISTMAS EVE NIGHT AND INTO
CHRISTMAS DAY MORNING, AS WEAK LOW-LEVEL JETTING RAMPS UP MOISTURE
ADVECTION AND ISENTROPIC ASCENT. BEST UPGLIDE LIFTING WILL BE NORTH
OF THE WARM FRONT AND OVER IN AND OH, BUT STILL HAVE GOOD AMOUNT OF
POPS ACROSS THE NORTHERN HALF OF THE CWA.
ON AND OFF LIGHT RAIN CHANCES WILL BE POSSIBLE THROUGHOUT CHRISTMAS
DAY AS WE REMAIN IN THAT PROGRESSIVE NW FLOW. DESPITE THE RELATIVELY
HIGH POPS THROUGH THIS PERIOD, OVERALL QPF WILL BE QUITE MEAGER,
WITH TOTAL QPF UNDER 0.10" POSSIBLE. TEMPERATURES ARE EXPECTED TO BE
ABOVE NORMAL ONCE AGAIN, WITH HIGHS REACHING THE MID TO UPPER-60S.
WE'LL END UP SHORT OF THE MAX TEMP RECORDS, BUT SHOULD BE THE
WARMEST CHRISTMAS SINCE 2021, WHICH WAS THE WARMEST XMAS ON RECORD
FOR OUR CLIMATE SITES.
===== FRIDAY INTO NEXT WEEKEND =====
THE UPPER FLOW FLATTENS OUT ON FRIDAY, TAKING ON A MORE PROGRESSIVE
ZONAL FLOW PATTERN. HOWEVER, LOW LEVEL WAA REMAINS STRONG, AND
SUPPRESSES OUR DIURNAL RANGE ON TEMPS. AS A RESULT, FRIDAY MORNING
LOW TEMPERATURES COULD END UP BREAKING WARM MIN RECORDS, WITH
FORECAST TEMPS IN THE UPPER 50S AND LOW 60S. GIVEN THE RELATIVELY
WARM START, TEMPS COULD END UP PUSHING 70F ON FRIDAY, WITH MOSTLY
DRY CONDITIONS AND JUST SOME LOW-END POPS.
OUR NEXT CHANCE FOR RAIN COMES OVER THE WEEKEND AS ANOTHER COLD
FRONT APPROACHES THE REGION. A WEST COAST UPPER TROUGH WILL EJECT
ACROSS THE MOUNTAIN WEST AND QUICKLY INTO THE PLAINS BEFORE SUNDAY.
IT IS POSSIBLE WE COULD SEE THIS SYSTEM PHASE WITH THE NORTHERN
STREAM, BUT DETERMINISTIC MODELS HAVE BEEN SLIGHTLY SLOWER WITH THE
PHASING TODAY, WHICH RESULTS IN A LESS-AMPLIFIED LINE OF SHOWERS
PASSING THROUGH ON SUNDAY. LOW CONFIDENCE REMAINS FOR THE POPS OVER
THE WEEKEND AS THE GUIDANCE IS TOO VARIED AT THIS TIME.
THERE IS HIGHER CONFIDENCE IN TEMPS FALLING BEHIND THE FRONT, WITH
CANADIAN HIGH PRESSURE BUILDING INTO THE OHIO VALLEY BY SUNDAY NIGHT
AND MONDAY. TEMPS SUNDAY NIGHT COULD DROP INTO THE 20S, WITH WIND
CHILLS IN THE TEENS POSSIBLE.
AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/
ISSUED AT 1223 PM EST MON DEC 22 2025
VFR CONDITIONS CONTINUE THIS AFTERNOON, THOUGH INCOMING LOWERING
CIGS AND RAIN CHANCES WILL IMPACT FLIGHT CATEGORIES BY THIS EVENING.
MVFR STRATUS DECK AND -SHRA ARE EXPECT TO SPREAD THROUGHOUT THE AREA
THIS EVENING. SFC WINDS INCREASE AS A LLJ STRENGTHENS OVERHEAD,
LEADING TO SOUTHERLY SFC WINDS GUSTING OVER 20KTS AFTER 00Z, AND
LLWS DURING THE OVERNIGHT. LIGHT RAIN SHOULD TAPER OFF BY MORNING
FOR MOST TERMINALS, BUT THE BEST CHANCE FOR LINGERING PRECIP
TOMORROW MORNING WILL BE FOR BWG. OTHERWISE, MVFR CIGS CONTINUE
TOMORROW, WITH HNB HAVING THE BEST CHANCE OF DROPPING TO IFR BEFORE
12Z.
LMK WATCHES/WARNINGS/ADVISORIES
KY...NONE.
IN...NONE.
SHORT TERM...CJP
LONG TERM...CJP
AVIATION...CJP
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