042
FXUS63 KIWX 301758 CCA
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
157 PM EDT TUE JUN 30 2026
KEY MESSAGES
- EXTREME HEAT WARNING REMAINS IN EFFECT AREA-WIDE THROUGH
THURSDAY EVENING. DAILY HIGHS IN THE 90S AND HEAT INDICES
BETWEEN 100 TO 110 DEGREES ARE EXPECTED.
- NEAR RECORD WARM OVERNIGHT LOWS IN THE MID 70S WILL OFFER LITTLE
TO NO RELIEF FROM THE HEAT AT NIGHT.
- HIGHS IN THE UPPER 80S TO LOW 90S FOR THE 4TH OF JULY WITH
20-50% CHANCES FOR RAIN AND STORMS.
- REMAINING WARM THROUGH EARLY NEXT WEEK WITH HIGHS IN THE 80S
AND PERIODIC CHANCES FOR RAIN AND STORMS.
DISCUSSION
ISSUED AT 155 PM EDT TUE JUN 30 2026
AN AMPLIFIED, DOMINANT UPPER LEVEL RIDGE WILL BRING VERY HOT AND
HUMID CONDITIONS THROUGH AT LEAST THURSDAY, JULY 2ND. AS SURFACE
HIGH PRESSURE BUILDS OVER THE SOUTHEAST US, SOUTHWEST FLOW INTO OUR
AREA CONTINUES TO USHER IN VERY HUMID AIR (DEWPOINTS IN THE MID 70S)
DUE TO A DEVELOPING CONNECTION WITH THE GULF. WITH SUCH A HUMID
AIRMASS, IT CAN BE DIFFICULT TO ACHIEVE TEMPERATURES ABOVE THE MID
TO UPPER 90S IN OUR FORECAST AREA. WHILE REACHING 100 DEGREES IS NOT
OUT OF THE QUESTION ON WEDNESDAY AND/OR THURSDAY (PARTICULARLY IN NW
OHIO), NBM PROBABILITIES ARE VERY LOW AT 15% OR LESS. AN EXTREME
HEAT WARNING REMAINS IN EFFECT FOR THE ENTIRE FORECAST AREA THROUGH
THURSDAY. DAYTIME HIGHS WILL BE IN THE LOW TO MID 90S EACH DAY
THROUGH THURSDAY WITH PEAK AFTERNOON HEAT INDICES BETWEEN 100 TO 110
DEGREES. NEAR RECORD WARM LOWS IN THE MID 70S OVER THE NEXT FEW
NIGHTS WILL OFFER VERY LITTLE TO NO REPRIEVE FROM THE HEAT. DUE TO
THE DURATION AND INTENSITY OF THE LATE JUNE/EARLY JULY HEATWAVE,
HEATRISK WILL BE MAXED OUT AT MAJOR TO EXTREME ACROSS THE AREA TODAY
THROUGH THURSDAY. DESPITE IT BEING SUMMER, WHICH IS TYPICALLY THE
HOTTEST TIME OF YEAR FOR OUR AREA, TAKE PRECAUTIONS IN THE HEAT TO
ENSURE YOU ARE STAYING COOL AND REDUCING RISKS FOR HEAT RELATED
ILLNESSES!
AS THE UPPER LEVEL RIDGE FLATTENS AND BEGINS TO BREAK DOWN INTO
EARLY JULY, MODEL GUIDANCE REINTRODUCES RAIN/STORM CHANCES TO OUR
AREA JUST IN TIME FOR THE 4TH OF JULY WEEKEND. EXACT DETAILS ARE
MURKY AND CONFIDENCE IS VERY LOW IN EXACT TIMING/PLACEMENT OF
RAIN/STORMS, BUT WE WILL HAVE TO MONITOR FOR COMPLEXES OF STORMS
(MCSS) THAT RIDE THE PERIPHERY OF THE FLATTENING RIDGE. OUR 4TH OF
JULY FORECAST CURRENTLY HAS HIGHS IN THE UPPER 80S TO LOW 90S WITH
20-50% CHANCES FOR RAIN AND STORMS. WHILE IT MAY BE SLIGHTLY
'COOLER' INTO EARLY NEXT WEEK WITH HIGHS IN THE 80S, THE LONG TERM
PATTERN CONTINUES TO FAVOR ABOVE NORMAL TEMPERATURES THROUGH MID
JULY.
AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/
ISSUED AT 105 PM EDT TUE JUN 30 2026
PESKY MVFR STRATUS HAS FINALLY MIXED OUT, BUT CU BASES STILL IN
THE UPPER END OF MVFR TO LOW VFR WHICH POSES A BIT OF A
CHALLENGE IN THE TAFS. SATELLITE SHOWS OVERALL COVERAGE STARTING
TO DECREASE AT BOTH LOCATIONS, SO OPTED FOR A FEW HOUR TEMPO
GROUP MENTION AT KSBN (ALTHOUGH COULD BE GONE WITHIN THE NEXT
HOUR OR SO). DELAY IN THE START OF FULL MIXING HAS DELAYED SOME
OF THE STRONGER WIND GUSTS. THESE SHOULD PICK UP WITH TIME, THEN
DIMINISH NEAR/AFTER SUNSET.
IWX WATCHES/WARNINGS/ADVISORIES
IN...EXTREME HEAT WARNING UNTIL 8 PM EDT /7 PM CDT/ THURSDAY FOR
INZ005>009-012>015-017-018-020-022>027-032>034-103-104-
116-203-204-216.
OH...EXTREME HEAT WARNING UNTIL 8 PM EDT THURSDAY FOR OHZ001-002-
004-005-015-016-024-025.
MI...EXTREME HEAT WARNING UNTIL 8 PM EDT THURSDAY FOR MIZ078>081-
177-277.
AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR MIZ177-277.
MARINE...NONE.
DISCUSSION...JOHNSON
AVIATION...BROWN
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