456
FXUS61 KILN 050338
AFDILN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON OH
1138 PM EDT FRI SEP 4 2026
WHAT HAS CHANGED
NO MAJOR CHANGES
KEY MESSAGES
1) ONE OR MORE COMPLEXES OF STRONG TO SEVERE THUNDERSTORMS WILL BE
POSSIBLE DURING THE EARLY MORNING HOURS ON SATURDAY AND THEN AGAIN
SATURDAY AFTERNOON INTO THE EVENING. ANY STORMS THAT DEVELOP MAY
PRODUCE LOCALLY HEAVY RAINFALL.
2) A QUIETER AND COOLER PATTERN IS EXPECTED FOR THE END OF THE
WEEKEND INTO THE FIRST HALF OF THE WORK WEEK.
DISCUSSION
KEY MESSAGE 1)
3:30Z UPDATE--
RECENT RADAR IMAGERY DEPICTS SCATTERED CONVECTION ACROSS EASTERN
ILLINOIS, LAKE MICHIGAN, AND WESTERN MICHIGAN AS OF 3:15Z THIS
MORNING. EVENING CAMS SUGGEST THIS ACTIVITY GROWING UPSCALE AND
MOVING SOUTHEASTWARD. THE BIG QUESTION REMAINS AS TO WHETHER THIS 1).
HOLDS TOGETHER LONG ENOUGH TO ORGANIZE ITSELF INTO A COLD POOL DRIVEN
MCS AND 2). DIVES DOWN INTO THE ILN FORECAST AREA.
ASSUMING THINGS DO HOLD TOGETHER AND TRANSLATE THIS FAR SOUTH...
WHILE WE'VE LOST MOST OF OUR SB INSTABILITY, RECENT ACARS FROM CMH,
IND, AND CVG INDICATE AROUND 1500-2000 J/KG OF MUCAPE AND 900+ J/KG
OF DCAPE. ILN'S 00Z SOUNDING CAPTURED 1.76 INCH PWATS. MEANWHILE,
DEEP LAYER SHEAR CONTINUES TO BE SOMEWHAT LACKING. 00Z SOUNDING
CAPTURED 25ISH KNOTS OF 0-6KM SHEAR, WHICH ISN'T OVERLY ROBUST.
HOWEVER, THE OVERALL MID- LEVEL FLOW OUT OF THE NORTHWEST WOULD
SUGGEST THAT STEERING FLOW COULD AT LEAST PROPAGATE STORMS DOWN INTO
OUR AREA. GIVEN THE ABOVE, A DAMAGING WIND THREAT SEEMS TO BE THE
HIGHEST RISK FOR OUR AREA. THE SIGNIFICANT HAIL PARAMETER HAS A SMALL
CIRCLE NEAR THE OH/IN BORDER, WHERE INSTABILITY IS DEEPER, SO
WOULDN'T RULE OUT SOME LARGE HAIL EITHER. PWATS ABOVE THE
CLIMATOLOGICAL 90TH % CONTINUE THE HEAVY RAINFALL THREAT, ESPECIALLY
WHERE STORMS MOVE OVER REPEATEDLY. AGAIN... THAT'S ALL IF THE SYSTEM
IS ABLE TO MAKE IT THIS FAR. TIME WILL TELL.
LOOKING AHEAD--
AS THE STATIONARY BOUNDARY THAT HAS BEEN SPLAYED OUT ACROSS OUR AREA
CONTINUES TO SAG SOUTH AS A COLD FRONT, SHOWERS AND THUNDERSTORMS
WILL ONCE AGAIN BE POSSIBLE. HIGH PROBABILITIES FOR THUNDERSTORM
CHANCES EXISTS ALONG AND SOUTH OF I-70, LIKELY DURING THE AFTERNOON
AND INTO THE EVENING HOURS ON SATURDAY. ONCE AGAIN, THE MAIN THREATS
WILL BE DAMAGING WIND AND LOCALLY HEAVY RAINFALL. AGAIN, CONFIDENCE
IN PLACEMENT/TIMING OF STORMS (OR WHETHER STORMS ACTUALLY FIRE OFF)
IS LOW.
KEY MESSAGE 2)
BY SUNDAY, LARGE SCALE RIDGING BUILDS INTO OUR WEST, HERALDING IN
NORTHERLY FLOW AND A BROAD AREA OF SURFACE HIGH PRESSURE. THIS
TRANSLATES TO QUIETER AND COOLER CONDITIONS, WITH HIGHS ON SUNDAY AND
MONDAY ONLY REACHING THE LOW 80S, WHILE OVERNIGHT LOWS FALL INTO THE
LOW 60S/UPPER 50S. UNFORTUNATELY, THIS REPRIEVE IS SHORT LIVED AS
THE BULK OF THE RIDGE CONTINUES TO PUSH EAST INTO OUR AREA, BRINGING
A RETURN TEMPERATURES IN THE LOW 90S BY MID WEEK. A DISTURBANCE TO
OUR NORTH LOOKS TO BRING THE NEXT CHANCES FOR PRECIPITATION MID-WEEK
AS IT DRAGS A COLD FRONT THROUGH THE GREAT LAKES REGION, THOUGH WE'RE
STILL A BIT FAR OUT FOR DETAILS.
AVIATION /02Z SATURDAY THROUGH WEDNESDAY/
AN AFTERNOON ROUND OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO
DIMINISH IN COVERAGE THIS EVENING ALLOWING THE RETURN OF VFR
CONDITIONS. OVERNIGHT, SHOWERS AND THUNDERSTORMS ARE POSSIBLE AFTER
0600Z ALTHOUGH EXACT TIMING AND COVERAGE IS DIFFICULT TO PINPOINT.
SOME MVFR CEILINGS ARE POSSIBLE AT THE COLUMBUS SITES TONIGHT.
FOR SATURDAY, VFR CONDITIONS WITH SOME DIURNAL CUMULUS IS EXPECTED.
ISOLATED SHOWERS AND STORMS ARE POSSIBLE ONCE AGAIN.
LIGHT WESTERLY FLOW OVERNIGHT INCREASES AND BECOMES NORTHWESTERLY ON
SATURDAY.
OUTLOOK...THUNDERSTORMS POSSIBLE AT TIMES THROUGH SATURDAY.
ILN WATCHES/WARNINGS/ADVISORIES
OH...NONE.
KY...NONE.
IN...NONE.
DISCUSSION...AIENA
AVIATION...CAMPBELL
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