866
FXUS63 KIND 250519
AFDIND
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE INDIANAPOLIS IN
1219 AM EST THU DEC 25 2025
KEY MESSAGES
- DENSE FOG ADVISORY OVERNIGHT...THROUGH 11 AM CHRISTMAS DAY
- CLOUDY AND DREARY CONDITIONS FOR CHRISTMAS, TURNING WARMER TOWARDS
THE WEEKEND
- TRANSITION BACK TO MUCH COLDER CONDITIONS NEXT WEEK
FORECAST UPDATE
ISSUED AT 929 PM EST WED DEC 24 2025
THE PREMISE OF THE FORECAST REMAINS ON TRACK, WITH SLIGHT
ADJUSTMENTS TO ACCOUNT FOR LATEST TRENDS AND OBSERVATIONS. A WARM
FRONT CONTINUES TO STRENGTHEN AND PUSH NORTHWARD THIS EVENING. THIS
HAS LED TO AN INCREASE IN FOG DEVELOPMENT OVER PORTIONS OF CENTRAL
ILLINOIS AND SOUTHERN INDIANA. TO THE NORTH OF THIS FRONT, WEAK MID
LEVEL FORCING IS PUSHING EASTWARD, RESULTING IN SOME SHOWERS,
ESPECIALLY WHERE CLOUD DECKS STILL REMAIN ABOVE 1500 FEET DUE TO
SOME RESIDUAL DRY NEAR SURFACE AIR. THIS FORCING WILL CONTINUE TO
CREATE CHANCES FOR SHOWERS WITHIN SOME ELEVATED INSTABILITY, THE
QUESTION REMAIN ON IF THERE IS ENOUGH SATURATION ABOVE THE PBL TO
CREATE SHOWERS VS DRIZZLE. FOR NOW EXPECTED WIDESPREAD DRIZZLE, BUT
NEAR THE WARM FRONT, MOISTURE CONVERGENCE MAY RESULT IN SCATTERED
CONVECTIVE SHOWERS AT TIMES THROUGH 09Z.
STRATUS WILL LOWER QUICKLY OVERNIGHT AS THE THE WARM FRONT STALLS
ACROSS CENTRAL INDIANA. THE INCREASE IN SUBSIDENCE FOLLOWING THE MID
LEVEL WAVE WILL FURTHER INCREASE WIDESPREAD FOG DEVELOPMENT LATE
TONIGHT INTO THE MORNING HOURS NORTH OF A TERRE HAUTE TO RUSHVILLE
LINE. THIS IS A BIT FURTHER SOUTH THAT ORIGINALLY EXPECTED, AND
THEREFOR THE ADVISORY FOR FOG HAS BEEN EXPANDED SOUTHWARD.
EVENTUALLY, THE FRONT WILL MOVE SOUTHWARD TOMORROW MORNING, SHIFTING
THE FOG THREAT FURTHER SOUTH; HOWEVER, THERE ARE SOME UNDERLYING
MITIGATING FACTORS CREATING LESS CERTAINTY IN FOG MAINTAINING OVER
SOUTHERN INDIANA TOMORROW.
SHORT TERM (THIS EVENING THROUGH THURSDAY)
ISSUED AT 231 PM EST WED DEC 24 2025
REST OF TODAY AND TONIGHT.
MAIN FOCUS FOR THE SHORT TERM PERIOD WILL BE TRACKING THE
DRIZZLE/LIGHT RAIN TONIGHT AND THE RETURN OF DENSE FOG ACROSS
CENTRAL INDIANA. AS OF EARLY THIS AFTERNOON, MOST OF CENTRAL INDIANA
IS UNDER MOSTLY CLEAR TO PARTLY CLOUDY SKIES, BUT THIS WILL RAPIDLY
BEGIN TO CHANGE TOWARDS THE EVENING HOURS AS HIGHER CLOUDS ADVECT IN
FROM THE WEST AND A SURGE OF MOISTURE MOVES IN FROM THE SOUTHEAST AS
WINDS GRADUALLY BEGIN TO RAMP UP. A FEW LIGHT SHOWERS WILL BE
POSSIBLE LATE THIS AFTERNOON AND EVENING, MAINLY ACROSS SOUTHWESTERN
INDIANA ASSOCIATED WITH WEAK LIFT IN THE HIGHER CLOUDS BUT COVERAGE
WILL BE FAIRLY MINIMAL WITH AMOUNTS GENERALLY NO HIGHER THAN A FEW
HUNDREDTHS OF AN INCH.
SATURATION NEAR THE SURFACE IS THEN EXPECTED TOWARDS MIDNIGHT WITH
DRIZZLE BECOMING THE PREDOMINANT PRECIPITATION TYPE AS CLOUD BASES
DROP TO JUST A COUPLE HUNDRED FEET. WIDESPREAD FOG IS EXPECTED
TONIGHT WITH DENSE FOG LIKELY ALONG THE WARM FRONT WHERE WINDS WILL
BE NEAR CALM. CONFIDENCE ON THE EXACT LOCATION OF THE WARM FRONT
REMAINS SOMEWHAT LOW WITH THE AXIS OF LONG-LASTING DENSE FOG LIKELY
ONLY A FEW COUNTIES FROM NORTH TO SOUTH. THERE SHOULDN'T BE MUCH
NORTH TO SOUTH MOVEMENT WITH THE FRONT WHICH COULD KEEP FOG AROUND
FOR MUCH OF THE NIGHT WHERE IT DOES FORM. AFTER CONSULTING WITH
NEIGHBORING OFFICES, WE DECIDED TO GO WITH A DENSE FOG ADVISORY
ALONG AND NORTH OF I-70 WHERE CONFIDENCE IN THE DENSE FOG IS
GREATEST. A SOUTHERLY EXPANSION MAY BE NEEDED AND WILL BE LOOKED AT
THROUGH THE EVENING.
THURSDAY.
OTHER THAN SOME RESIDUAL FOG DURING THE MORNING HOURS, QUIET ALBEIT
DREARY WEATHER IS EXPECTED FOR MUCH OF THE DAY WITH LIGHT
NORTHEASTERLY WINDS IN THE AFTERMATH OF THE EXITING LOW. SOUTHERLY
SURFACE FLOW NOW LOOKS TO REMAIN SOUTH OF THE FORECAST AREA WHICH
SHOULD KEEP THE WARMER 60S CLOSER TO THE OHIO RIVER. A FAIRLY
NOTABLE NORTH TO SOUTH TEMPERATURE GRADIENT IS LIKELY WITH A
POTENTIAL 15-20 DEGREE SWING BETWEEN NORTH CENTRAL INDIANA AND THE
OHIO RIVER. THERE MAY BE SOME LINGERING DRIZZLE, BUT WITH THE FLOW
BECOMING NORTHERLY, ISENTROPIC LIFT LOOKS MINIMAL WITH ANY FORCING
ABOVE THE CLOUD LAYER.
LONG TERM (THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 231 PM EST WED DEC 24 2025
CHRISTMAS NIGHT THROUGH FRIDAY...
A WEAK FRONTAL BOUNDARY SHOULD REMAIN POSITIONED OVER THE OHIO
VALLEY, STILL LOOKS TO BE ORIENTED OVER INDIANA AND GUIDANCE HAS
BEEN WAVERING THE LAST FEW DAYS, BUT WITH THE BROAD SURFACE RIDGE
DISPLACED TO THE NORTH THIS SHOULD KEEP THE BOUNDARY JUST SOUTH OF
THE INDY METRO AREA THROUGH CHRISTMAS NIGHT; HOWEVER, THE UPPER
LEVEL JET STRUCTURE STILL SUPPORTS A PROGRESSIVE PATTERN SETUP. THIS
INDICATES THE BOUNDARY WILL QUICKLY LIFT NORTH AND TURN LOW-LEVEL
FLOW SOUTHEASTERLY TO SOUTHERLY AS IT LIFTS NORTH OF CENTRAL IN.
GUIDANCE STILL INDICATES A WEAK MID-LVL SPEED MAX TO DEVELOP ACROSS
THE CENTRAL PLAINS EARLY FRI, AND APPEARS TO EXPAND A PRECIP
FOOTPRINT ACROSS THE OHIO VALLEY FRI MORNING. BUT THE CAVEAT TO
LINGERING PRECIP IS THAT THE SURFACE LOW LOOKS BE LACKING IN A
ISALLOBARIC GRADIENT, INDICATING THAT LOW CEILINGS COULD DEVELOP
MIDDAY WITH A PERSISTENT STRATUS DECK UNDER A LIGHT SOUTHERLY MOIST
FLOW. GUIDANCE CONTINUES TO INDICATE TEMPS IN THE 60S, BUT IF CLOUD
COVER IS SUBSTANTIAL THIS COULD BE REDUCED DUE TO THE ABUNDANCE OF
SOLAR BLOCKING AND KEEP TEMPS IN THE UPR 50S.
FRI NGT INTO SAT... MID-LVL HEIGHT RISES SHOULD SLIDE EAST OVER
INDIANA, WHICH WILL FURTHER REDUCE THE PRESSURE FIELDS WITHIN THE
BOUNDARY LAYER. THAT INDICATES THAT WE COULD HAVE ANOTHER PERIOD OF
SOME PATCHY FOG, WITH MILD TEMPS GIVEN THE LACK OF ANY COLD AIR
ADVECTION BLEEDING BACK INTO INDIANA. SAT SHOULD FEATURE ANOTHER
MILD DAY WITH THE BOUNDARY TRYING TO SAG SOUTH YET AGAIN, BUT THE
LACK OF A FORCING MECHANISM IN THE UPPER LEVELS SHOULD KEEP THIS
FEATURE DISPLACED TO THE NORTH.
SUN THROUGH WED...THEN HEIGHTS CONTINUE TO RISE MARGINALLY LATE SAT
NGT, SETTING SUN UP TO BE ANOTHER VERY MILD DAY UNDER STRONGER
SOUTHERLY FLOW AS THE UPSTREAM TROUGH DIGS INTO THE SOUTHWEST CONUS.
THIS WILL FURTHER AMPLIFY THE DOWNSTREAM RIDGE OVER OHIO VALLEY.
ENSEMBLES CONTINUE TO FAVOR A SYSTEM DEVELOPING ACROSS THE FOUR-
CORNERS REGION SUN EJECTING INTO THE SOUTHERN PLAINS AND POSSIBLY
FURTHER DEVELOPING WITH THE INCREASING FLOW OF WARM/MOIST AIR FROM
THE WEST GULF. THIS SHOULD BE A PROGRESSIVE SETUP AND QUICKLY PUSH
INTO THE OHIO VALLEY BY LATE SUN INTO MON. CURRENT INDICATIONS ARE
THAT THIS WILL BE A MAINLY RAIN SYSTEM BUT COLD AIR ADVECTION WILL
BE POURING IN FROM THE NORTHWEST MON, AS THE SETUP TURNS TO A
TYPICAL WINTER NORTHWEST FLOW. THIS THEN APPEARS TO BE THE MAIN
FEATURE HEADING INTO THE FINAL DAYS OF THE YEAR WITH MUCH MORE OF A
TYPICAL LATE DEC SETUP OF COLD TEMPS AND PERIODIC CHANCES FOR SOME
SNOW SHOWERS.
AVIATION (06Z TAF ISSUANCE)
ISSUED AT 1219 AM EST THU DEC 25 2025
IMPACTS:
- LIFR/VLIFR CIGS...IFR/LIFR VIS, OVERNIGHT INTO CHRISTMAS MORNING
- IMPROVEMENT TO IFR ON CHRISTMAS AT KLAF, AND POSSIBLY KIND...WITH
LIFR LIKELY MAINTAINED AT KHUF/KBMG THROUGH THE TAF PERIOD
DISCUSSION:
MAINLY LIFR/VLIFR CEILINGS THROUGH DAWN OVER CENTRAL INDIANA
TERMINALS AS FRONTAL BOUNDARY QUIETLY CROSSES THE REGION...AMID
LIGHT WINDS AND INCREASING COVERAGE OF BR/DZ...WHICH WILL ALSO BRING
DETERIORATING VISIBILITY TO MAINLY IFR/LIFR LEVELS. GRADUAL
IMPROVEMENT FROM NORTH TO SOUTH CHRISTMAS DAY, WITH VIS LEADING, AND
CIGS HOPEFULLY CLIMBING TO IFR AT KLAF/KIND DURING THE AFTERNOON,
AND MVFR POSSIBLE AT KLAF BY 00Z FRIDAY. KHUF/KBMG TO POTENTIALLY
STAY UNDER LIFR STRATUS THROUGH THE TAF PERIOD... WITH MODERATE
CONFIDENCE IN LIFR CIG RETURNING TO KIND AFTER 06Z FRIDAY.
LIGHT WINDS THROUGH THE REST OF THE OVERNIGHT WILL VEER FROM
SOUTHERLY TO 280-340 DEGREES BY 12Z. LIGHT BREEZES TO CONTINUE
VEERING CHRISTMAS DAY AS REGION RECEIVES SOUTHERN EDGE OF STRONGER
POLAR HIGH CROSSING ONTARIO/GREAT LAKES...WITH NORTHEAST WINDS AT
19Z, AND EASTERLY FLOW BY 00Z FRIDAY. SLIGHTLY ELEVATED WINDS TO
GUST TO 10-15KT BY 06Z FRIDAY.
IND WATCHES/WARNINGS/ADVISORIES
DENSE FOG ADVISORY UNTIL 11 AM EST THIS MORNING FOR INZ021-
028>031-035>049-051>057.
UPDATE...UPDIKE
SHORT TERM...WHITE
LONG TERM...BEACH
AVIATION...AGM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page