857
FXUS61 KILN 020005
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
705 PM EST SUN MAR 1 2026
WHAT HAS CHANGED
INCREASED COVERAGE AND AMOUNTS FOR SNOW, WITH SOME WINTRY MIX
LIKELY, FOR MONDAY MORNING.
KEY MESSAGES
1) MIXED WINTRY PRECIPITATION EXPECTED MONDAY MORNING, WITH
ACCUMULATING SNOW FOR SOME LOCATIONS, PARTICULARLY NEAR, AND JUST
NORTH OF, THE OHIO RIVER. THE MONDAY MORNING COMMUTE WILL BE
IMPACTED BY THIS WINTRY PRECIPITATION.
2) WARMER AND WETTER CONDITIONS EXPECTED FROM TUESDAY THROUGH THE
REST OF THE WEEK, LEADING TO INCREASED POTENTIAL FOR AREAL AND RIVER
FLOODING LATE WEEKEND INTO THE UPCOMING WEEKEND.
DISCUSSION
KEY MESSAGE 1) MIXED WINTRY PRECIPITATION EXPECTED MONDAY MORNING,
WITH ACCUMULATING SNOW FOR SOME LOCATIONS, PARTICULARLY NEAR, AND
JUST NORTH OF, THE OHIO RIVER. THE MONDAY MORNING COMMUTE WILL BE
IMPACTED BY THIS WINTRY PRECIPITATION.
DRY CONDITIONS HAVE BRIEFLY SETTLED INTO THE REGION AS A STRONG SFC
HIGH DRIFTS TO THE SE THROUGH THE GREAT LAKES REGION INTO THE
INTERIOR NE CONUS BY TONIGHT. COOLER AND DRIER AIR WILL FILTER INTO
THE AREA THROUGH THE DAYTIME TODAY, WITH ALL EYES ON AN THE APPROACH
OF A S/W INTO THE OH VLY LATE TONIGHT THROUGH MONDAY MORNING.
AS WE PROGRESS INTO TONIGHT, AN INCREASE IN LIFT/MOISTURE WILL
SPREAD E THROUGH THE REGION FROM THE MID MS RVR VLY INTO THE OH VLY,
WITH VERY DRY BL AIR ENTRENCHED IN THE ILN FA AHEAD OF THE
APPROACHING SYSTEM. THIS /VERY/ DRY AIR WILL HELP THE PROFILE WET
BULB AS THE MOISTURE SPREADS E INTO THE PREDAWN HOURS, WITH PCPN
FALLING INTO AN INITIALLY WARM/DRY NEAR-SFC LAYER. THIS WILL HELP
THE PROFILE COOL TO NEAR/BELOW THE FREEZING MARK, SUPPORTING A
NARROW BAND OF STEADY FRONTOGENETICALLY-FORCED SN FROM EC/SE IN
THROUGH THE TRI-STATE INTO NRN KY AND SW OH INTO SOUTH-CENTRAL OH,
WITH SOME IP/FZRA RAIN FAVORED JUST SOUTH OF THE PRIMARY BAND OF
SN. IT IS IMPORTANT TO NOTE THAT, EVEN NEAR/N OF THE OH RVR WHERE SN
IS THE FAVORED PREDOMINANT P-TYPE, A BRIEF MIX WITH FZRA/IP WILL BE
POSSIBLE BOTH NEAR THE ONSET AND NEAR THE END OF THE PRIMARY PCPN
BAND. NEAR THE ONSET (~08Z-10Z), THE COLUMN WILL BE WET-BULBING AND
COOLING, BUT MAY NOT ENTIRELY BE BELOW FREEZING AS THE PCPN INITIALLY
REACHES THE GROUND. NEAR THE END (~14Z-16Z), ENOUGH WAA INTO THE
H9-H8 LAYER, AS WELL AS A LOSS OF MOISTURE IN THE DGZ, MAY ALLOW FOR
SOME MIXING WITH FZRA/IP. FAR SRN PARTS OF THE AREA FROM CARROLL CO
KY TO LEWIS CO KY MAY REMAIN PREDOMINANTLY A MIX OF FZRA/IP/RA
THROUGH THE ENTIRETY OF THE EVENT (WITH LITTLE/NO SN) DUE TO WARMER
BL CONDITIONS, BUT CERTAINLY A FEW HUNDREDTHS OF AN INCH OF ICE WILL
BE POSSIBLE IN THESE AREAS WHERE PROLONGED FZRA IS MAINTAINED. THIS
WILL BE ESPECIALLY THE CASE ON ELEVATED SURFACES, SUCH AS UNTREATED
BRIDGES/OVERPASSES AND TREES.
THE HIGH-RES GUIDANCE CONTINUES TO SHOW A SLIGHTLY MORE ROBUST
SOLUTION, PARTICULARLY FOR THE SOUTHERN HALF OF THE ILN FA, WITH
STEADIER PCPN AND A SLIGHTLY COOLER BL (OWING TO DRIER ANTECEDENT BL
CONDITIONS). THE PRIMARY STORY HERE IS THAT IT IS LIKELY THAT A SWATH
OF WINTRY PRECIPITATION WILL WORK ITS WAY ACROSS THE SOUTHERN HALF
OF THE ILN FA MONDAY MORNING, WITH A NARROW W-E ORIENTED BAND OF 1-2"
OF SNOW LIKELY SOMEWHERE NEAR/N OF THE OH RVR TO JUST S OF THE I-70
CORRIDOR. DUE TO THE ORIENTATION OF THIS BAND AND A SUFFICIENTLY-
COOL BL PROFILE, SOME LOWER-PROBABILITY POTENTIAL EXISTS THAT BANDING
COULD PRODUCE UP TO 3 INCHES IN ISOLATED LOCATIONS. IN ADDITION TO
THIS, SOME BRIEF MIX WITH IP OR FZRA ALSO APPEARS POSSIBLE, EVEN
WHERE THE HEAVIEST SNOW OCCURS. THE SURFACE WILL REMAIN LOCKED IN ENE
FLOW, BUT AT 925MB-850MB, SOME SOUTHERLY FLOW WILL BRING OVERRUNNING
THETA-E ADVECTION, SUPPORTING THE DEVELOPMENT OF AN ELEVATED WARM
(ABOVE FREEZING) LAYER PAST 12Z. MODEL SOUNDINGS LOOK FAVORABLE FOR
AT LEAST A BRIEF PERIOD OF FZRA/IP TO OCCUR, PARTICULARLY IN NORTHERN
KY AND FAR SOUTHERN OH BY MID-MORNING AS WE LOSE SOME SATURATION IN
THE DGZ. CONFIDENCE IN WHERE EXACTLY THE MIX OF P-TYPES COULD SET UP
IS QUITE LOW, BUT HAS BEEN INCLUDED IN THE FORECAST FOR ROUGHLY THE
SOUTHERN THIRD OF THE ILN FA.
THE CONCERNING PART OF THIS SETUP IS THAT IT WILL BE MOVING THROUGH
RIGHT DURING THE MONDAY AM COMMUTE. WHILE THE ROAD TEMPS MAY
INITIALLY BE ABOVE FREEZING, ELEVATED SURFACES, SUCH AS BRIDGES AND
OVERPASSES, WILL SUPPORT SOME ACCUMULATION DUE TO THE STEADIER RATES,
WITH UNTREATED ROAD TEMPS GENERALLY IN THE LOWER TO MID 30S. THE
SOLAR INSOLATION WILL HELP CONDITIONS TO IMPROVE BY ABOUT 10 AM OR
SO, BUT MOST OF THE STEADIEST WINTRY PCPN WILL BE SLOWLY TAPERING OFF
BY THEN ANYWAY, WITH A TRANSITION TO PLAIN RAIN EXPECTED INTO EARLY
AFTERNOON. THIS BEING SAID, IT ALSO APPEARS POSSIBLE THAT SURFACE
TEMPS WILL NOT WARM AS FAST AS PREVIOUSLY EXPECTED. IF THAT OCCURS,
SOME PATCHY LIGHT SNOW OR MIXED PRECIPITATION COULD CONTINUE INTO THE
EARLY AFTERNOON HOURS (MAINLY IN NRN KY), BUT IMPACTS SHOULD WANE
DUE TO WARMING ROAD TEMPS. DUE TO THE EXPECTATIONS FOR IMPACTS FOR
THE MONDAY MORNING COMMUTE, A WINTER WEATHER ADVISORY HAS BEEN ISSUED
FOR AREAS WHERE THE 2" SNOW CRITERIA EXISTS FOR AN ADVISORY AND
WHERE THE GREATEST IMPACTS ARE EXPECTED DUE TO ACCUMULATING SNOW AND/OR
LIGHT ICE ACCRETION.
KEY MESSAGE 2) WARMER AND WETTER CONDITIONS EXPECTED FROM TUESDAY
THROUGH THE REST OF THE WEEK, LEADING TO INCREASED POTENTIAL FOR
AREAL AND RIVER FLOODING LATE WEEKEND INTO THE UPCOMING WEEKEND.
A PRONOUNCED SHIFT IN THE LARGE-SCALE WEATHER PATTERN IS EXPECTED TO
BEGIN TUESDAY. ON THE WRN PERIPHERY OF THE BERMUDA HIGH, DEEP-LAYER
S/SW FLOW WILL BECOME ESTABLISHED OVER THE SE CONUS. A
SIGNIFICANT/PROLONGED FEED OF ANOMALOUS WARMTH AND MOISTURE IS
EXPECTED TO DEVELOP FROM THE GULF THROUGH THE DEEP SOUTH, THE LOWER
AND MID MS VLY, AND INTO THE TN/OH VLYS. FOR THE ILN CWA, BL FLOW IS
EXPECTED TO SWITCH TO SOUTHERLY AT SOME POINT ON TUESDAY, AND THEN
MORE ROBUSTLY IN THE WARM SECTOR BY WEDNESDAY. THIS THETA-E
ADVECTION WILL MARK THE START OF BOTH A WARMING AND MOISTENING
TREND. MAX TEMPS IN THE 50S TO LOWER 60S ARE EXPECTED TUESDAY,
WARMING EACH DAY AND GETTING INTO THE LOWER TO MID 70S BY FRIDAY,
WITH TEMPS WELL ABOVE NORMAL FOR THE FORESEEABLE FUTURE.
ON THE PERIPHERY OF THE ZONE OF HIGHER THETA-E, REPEATED ROUNDS OF
RAIN ARE EXPECTED TO DEVELOP. INITIALLY ON TUESDAY, RAIN WILL BE
ASSOCIATED WITH THE WARM FRONT MOVING N THROUGH THE AREA. RAIN/STORM
CHANCES LATER IN THE WEEK WILL BE DETERMINED BY THE TIMING OF
ADDITIONAL WAVES MOVING E/NE THROUGH THE MID MS RVR VLY, OH VLY, AND
GREAT LAKES. SOME EMBEDDED AREAS OF HEAVY RAIN, AND CERTAINLY SOME
CONVECTION, WILL OCCUR AT TIMES, ALTHOUGH TIMING OF THE SPECIFIC
ROUNDS OF HEAVIEST RAIN REMAINS DIFFICULT TO DETERMINE AT THIS TIME.
FROM A SYNOPTIC PATTERN STANDPOINT, THIS IS A SETUP THAT PROVIDES
THE POTENTIAL FOR HEAVY RAIN AND POSSIBLE FLOODING -- FOCUSED TO THE
W AND SW OF THE ILN CWA, BUT EXTENDING INTO THE ILN CWA TO SOME
DEGREE AS WELL. STILL EARLY TO GET INTO SPECIFICS ABOUT EXACTLY
WHERE OR WHEN, BUT THE OVERALL POTENTIAL WOULD INCREASE WITH
ADDITIONAL ROUNDS OF RAIN GOING LATER IN THE WEEK OR EVEN INTO NEXT
WEEKEND. ENSEMBLE GUIDANCE REMAINS IN GOOD AGREEMENT WITH HIGH
(>70%) POTENTIAL FOR TOTAL RAINFALL IN EXCESS OF 2" FOR AT LEAST
PARTS OF THE ILN FA TUESDAY THROUGH SATURDAY, WITH CERTAINLY SOME
POTENTIAL FOR HIGHER AMOUNTS DEPENDING ON WHERE THE MOST PROLONGED
TRAINING OF CONVECTION DEVELOPS.
IT IS NOT OF THE QUESTION THAT SOME STRONG STORMS COULD OCCUR AT
SOME POINT LATE WEEK, BUT STILL TOO EARLY TO LOOK AT WHEN OR WHERE
THAT MAY OCCUR.
AVIATION /00Z MONDAY THROUGH FRIDAY/
SOME CHANGES CONTINUE TO BE MADE WITH THE UPCOMING WINTRY
PRECIPITATION EVENT MOVING IN LATE TONIGHT INTO EARLY MONDAY
MORNING. MOST SITES SEE SNOW TO START, BUT CONFIDENCE IS INCREASING
ON PERIODS OF SLEET AND FREEZING RAIN ACROSS CVG/LUK INTO MONDAY
MORNING. AS PRECIPITATION OCCURS, MVFR CIGS BECOME MORE LIKELY, ALONG
WITH IFR/MVFR VIS IN PRECIPITATION. RECENT TRENDS HAVE THE
PRECIPITATION FARTHER NORTH, SO THIS HAS RESULTED IN MORE PESSIMISTIC
CONDITIONS FOR DAY AND CMH/LCK. PRECIPITATION IS ALSO EXPECTED TO
LAST A FEW MORE HOURS INTO MONDAY, WITH IMPROVEMENTS AFTER 18Z. CIGS
DECREASE ONCE AGAIN MONDAY NIGHT AS RAIN SHIFTS NORTHWARD INTO THE
AREA.
NE FLOW AROUND 10-15KTS THIS AFTERNOON WILL GO MORE EASTERLY AROUND
10KTS THIS EVENING, CONTINUING THROUGH THE DAYTIME MONDAY.
OUTLOOK...OCCASIONAL MVFR CONDITIONS, PERHAPS WITH RAIN, WILL OCCUR
AT TIMES FROM LATE MONDAY THROUGH FRIDAY.
ILN WATCHES/WARNINGS/ADVISORIES
OH...WINTER WEATHER ADVISORY FROM 3 AM TO 11 AM EST MONDAY FOR
OHZ070>073-077>082-088.
KY...WINTER WEATHER ADVISORY FROM 3 AM TO 11 AM EST MONDAY FOR
KYZ089>100.
IN...WINTER WEATHER ADVISORY FROM 3 AM TO 11 AM EST MONDAY FOR INZ066-
073>075-080.
DISCUSSION...KC
AVIATION...MCGINNIS
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