375  
FXUS63 KIWX 160607  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
207 AM EDT WED SEP 16 2026  
   
KEY MESSAGES
 
 
- HUMID WITH ROUNDS OF SHOWERS AND THUNDERSTORMS THROUGH  
THURSDAY, BEST CHANCES THIS MORNING, AND THEN AGAIN LATER  
TONIGHT INTO THURSDAY MORNING (50-80%).  
 
- LOCALLY HEAVY RAINFALL AND FLOODING POSSIBLE TODAY INTO THURSDAY.  
 
- DRY AND LESS HUMID CONDITIONS ON FRIDAY FOLLOWED BY RENEWED  
OPPORTUNTIES FOR RAIN AND STORMS THIS WEEKEND.  
 

 
   
DISCUSSION
 
 
ISSUED AT 207 AM EDT WED SEP 16 2026  
 
A FRONTAL BOUNDARY AND ~2 INCH PWAT AXIS WILL HOVER IN WEST TO  
EAST FASHION OVER THE AREA THROUGH AT LEAST THURSDAY WITH  
PERIODIC SHOWER/STORM CHANCES. LOCALLY HEAVY RAINFALL/FLASH  
FLOODING WILL BE THE PRIMARY CONCERN GIVEN THE HIGH MOISTURE  
CONTENT AND POTENTIAL FOR SEVERAL ROUNDS OF SLOW MOVING  
CONVECTION.  
 
FAVORABLE RIGHT ENTRANCE REGION UPPER SUPPORT, IN CONJUNCTION  
WITH AN INCOMING CONVECTIVELY AUGMENTED MID LEVEL IMPULSE  
(POTENTIAL MCV), SHOULD KEEP AT LEAST SCATTERED CONVECTION IN  
THE VICINITY OF THE THETA-E RIDGE THIS MORNING, ESPECIALLY  
ACROSS NORTHERN IN AND NORTHWEST OH. RAINFALL RATES HAVE BEEN  
IMPRESSIVE (OVER AN INCH IN 10-15 MINUTES), SO WILL CONTINUE TO  
MONITOR FLOODING GOING FORWARD.  
 
WEAK HEIGHT RISES ON THE NORTHERN FRINGES OF A STOUT UPPER LEVEL  
RIDGE SUGGEST SOME OVERALL SUBSIDENCE THIS AFTERNOON INTO THIS  
EVENING. HELD WITH LOWER POPS AS A RESULT DURING THIS TIME, BUT  
STILL CANNOT RULE OUT WIDELY SCATTERED CONVECTION WITHIN ANY POCKETS  
OF GREATER HEATING, MAINLY NEAR THE US 24 CORRIDOR. LATER TONIGHT  
INTO THURSDAY MORNING THEN FEATURES INCREASING CHANCES FOR  
ANOTHER ROUND OF STORMS AND POTENTIAL HYDRO ISSUES AS RENEWED  
WARM ADVECTION ENSUES WITHIN ANOTHER LOW LEVEL JET.  
 
THE BULK OF AVAILABLE MODEL GUIDANCE DOES PUSH THE EFFECTIVE FRONTAL  
ZONE OFF TO SOUTH-SOUTHWEST BY THURSDAY NIGHT INTO FRIDAY WITH BRIEF  
DRY AND LESS HUMID CONDITIONS. RAIN/STORM CHANCES THEN RETURN  
THIS WEEKEND AS PIECEMEAL SHORTWAVE ENERGY EJECTS EAST OUT OF  
THE INTERMOUNTAIN WEST, FORCING THE BOUNDARY AND INSTABILITY  
AXIS BACK NORTH INTO THE LOWER GREAT LAKES.  
 

 
   
AVIATION /06Z TAFS THROUGH 06Z THURSDAY/
 
 
ISSUED AT 1225 AM EDT WED SEP 16 2026  
 
CONTINUED MOISTURE TRANSPORT INTO A FRONTAL ZONE WILL LIKELY  
ALLOW FOR AN ADDITIONAL ROUND OF SHOWERS AND STORMS (AND BRIEF  
VIS RESTRICTIONS) THIS MORNING, BEST CHANCES LATER TONIGHT  
THROUGH THE LATE MORNING HOURS AS AN UPSTREAM MCV TRACKS IN. LOW  
VFR TO MVFR CONDITIONS EXPECTED TO BUILD IN JUST NORTH OF THE  
SFC PORTION OF THE FRONT OTHERWISE TODAY WITH CONFIDENCE ON ANY  
ADDITIONAL THUNDERSTORM ACTIVITY LOW (20-30%) BY THIS AFTERNOON-  
EVENING.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
OH...NONE.  
MI...NONE.  
MARINE...NONE.  
 

 
 

 
 
DISCUSSION...STEINWEDEL  
AVIATION...STEINWEDEL  
 
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