522
FXUS63 KIWX 051036
AFDIWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTHERN INDIANA
636 AM EDT WED AUG 5 2026
KEY MESSAGES
- DRY CONDITIONS THROUGH LATE AFTERNOON WITH SEASONABLE HIGHS IN
THE 80S.
- CHANCES (30-70 PERCENT) FOR SHOWERS AND STORMS THIS EVENING
AND PERSIST AT TIMES INTO FRIDAY. LOCALLY HEAVY RAIN IS
POSSIBLE.
- LOW CHANCES FOR SHOWERS AND STORMS SATURDAY INTO TUESDAY (20-40
PERCENT).
DISCUSSION
ISSUED AT 206 AM EDT WED AUG 5 2026
OVERALL UPPER LEVEL PATTERN IS TRANSITIONING TO A LONGWAVE
TROUGH WHICH WILL SETTLE IN FOR THE NEXT SEVERAL DAYS. A SERIES
OF WAVES WILL PASS THROUGH WITH TIMING AND STRENGTH DIFFERENCES
CAUSING CHALLENGES ON PRECIP CHANCES INTO AT LEAST THURSDAY
NIGHT. A WEAK COLD FRONT EXTENDED FROM NORTHERN LOWER MI TO
EASTERN IA. THIS FEATURE WILL EDGE EVER SO SLOWLY EAST WITH EACH
IMPULSE AND A MODEST LLJ ALLOWING FOR AREAS OF STORMS TO
DEVELOP AND MOVE N AND E. THE CURRENT AREA OF SHOWERS AND STORMS
WILL ATTEMPT TO EDGE EAST OVER THE NEXT SEVERAL HOURS, BUT
SHOULD WEAKEN AS IT OUTRUNS THE 20 TO 30 KT LLJ AS WELL AS
BETTER FORCING. A SOMEWHAT STRONGER TROUGH WILL INTERSECT THE
FRONTAL BOUNDARY, ALLOWING FOR A STRENGTHENING LLJ WITH
REDEVELOPMENT OF CONVECTION EXPECTED DURING THE DAY OVER EASTERN
IA. THE LLJ AND EASTERN MOVEMENT OF THE TROUGH WILL ALLOW SOME
CHANCE FOR THIS PRECIP TO MAKE IT INTO FAR W/NW AREAS LATE THIS
AFTERNOON AND MORESO THIS EVENING BUT IT WILL FIGHT TO MAKE IT
VERY FAR EAST AS THE FRONT SLOWS FURTHER. HAVE ATTEMPTED TO SLOW
ARRIVAL THIS AFTERNOON AND FOCUS HIGHEST (LIKELY) POPS IN W/NW
AREAS THIS EVENING BEFORE THE OVERALL AREA LIKELY WEAKENS.
THEREAFTER RUNNING WITH SLGT CHC TO CHC POPS GIVEN THE FRONT
SLOWLY EDGING INTO THE CWA AND STALLING/WASHING OUT WITH TIME.
MODELS VARY ON DEGREE OF POTENTIAL REDEVELOPMENT DURING THE DAY
THURSDAY, BUT WITH PLENTY OF MOISTURE AND LIMITED CAPE AT LEAST
MID TO HIGH CHC POPS WARRANTED WITH POSSIBILITY FOR HIGHER POPS
NEEDED DEPENDING ON OVERNIGHT CONVECTION IMPACTS. HIGH PWATS
WILL BRING A THREAT FOR HEAVY RAINFALL WITH THE GREATEST
CONCERNS EXISTING WHERE REPEATED CONVECTION OCCURS.
NO SIG CHANGES BEYOND THURS GIVEN CHALLENGES FOR OVERALL TIMING
AND IMPACTS FROM ADDITIONAL WAVES AS THE UPPER LEVEL TROUGH
REMAINS IN PLACE INTO EARLY NEXT WEEK. THE MAIN FOCUS FOR
GREATER HEAT WILL REMAIN OVER THE 4 CORNERS AREA THROUGH THE
WEEKEND WITH A SOMEWHAT MORE ZONAL FLOW BEGINNING TO SET UP NEXT
WEEK WHICH MAY ALLOW SOME OF THIS TO MOVE IN.
AVIATION /12Z TAFS THROUGH 12Z THURSDAY/
ISSUED AT 630 AM EDT WED AUG 5 2026
INITIAL AREA OF SHOWERS AND STORMS HAS EITHER WEAKENED OR
REMAINED NW OF BOTH SITES. ADDITIONAL CONVECTION CONTINUES TO
FESTER BACK ACROSS IA WITH A SLOW EASTWARD TRANSITION EXPECTED
THROUGH THE DAY. CONFIDENCE STILL REMAINS ON THE LOWER SIDE FOR
IMPACTS AT KSBN AND EVEN LOWER AT KFWA. BEST COURSE OF ACTION
FOR NOW IS STATUS QUO WITH LATER FORECASTS HOPEFULLY ABLE TO
HONE IN ON IMPACTS.
IWX WATCHES/WARNINGS/ADVISORIES
IN...NONE.
OH...NONE.
MI...NONE.
MARINE...NONE.
DISCUSSION...FISHER
AVIATION...FISHER
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