023  
FXUS63 KIWX 261007  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
607 AM EDT SAT SEP 26 2026  
   
KEY MESSAGES
 
 
- THIS WEEKEND, COOL, CRISP MORNINGS GIVE WAY TO AFTERNOON  
TEMPERATURES IN THE LOW-TO-MID 70S. TEMPERATURES TREND WARMER  
INTO THE EARLY WORK WEEK.  
 
- DRY CONDITIONS PERSIST UNTIL EARLY WEDNESDAY MORNING.  
 
- RAIN CHANCES TAKE OVER FROM THE MID WORK WEEK POTENTIALLY  
CONTINUING INTO THE WEEKEND. UNCERTAINTY STILL REMAINS WITH  
HEAVY RAIN/THUNDERSTORM CHANCES.  
 

 
   
DISCUSSION
 
 
ISSUED AT 124 AM EDT SAT SEP 26 2026  
 
A RELATIVELY VIGOROUS SHORTWAVE CONTINUES TO SINK SOUTHWARD THROUGH  
THE DAY TODAY DOING NOTHING MORE THAN PROVIDING A FEW CLOUDS TO THE  
AREA. THE COLUMN IS RATHER DRY AS SURFACE HIGH PRESSURE NOSES IN  
FROM THE NORTH. STILL THE AREA LOOKS ENTRENCHED ON THE WESTERN SIDE  
OF A REX BLOCK AS A STRONG UPPER LOW DEEPENS ALONG THE EAST COAST  
AND A HIGH PRESSURE SYSTEM SITS IN SOUTHEASTERN CANADA. THIS BLOCK  
HELPS TO DAMPEN A WAVE AS IT APPROACHES FROM THE WEST SUNDAY  
NIGHT/MONDAY AND THIS ALLOWS DRY WEATHER TO CONTINUE AS ANOTHER  
SURFACE HIGH APPROACHES FROM THE WEST LATER MONDAY INTO MONDAY  
NIGHT. FINALLY, A PACIFIC WAVE APPROACHES THE NORTHERN PLAINS AND  
WESTERN GREAT LAKES BETWEEN MONDAY AND TUESDAY HELPING TO KICK THE  
STALLED STRONG AREA OF LOW PRESSURE ALONG THE EAST COAST OUT TO SEA.  
 
THIS OPENS TO THE DOOR TO INCREASED MOISTURE AS A MID LEVEL WAVE  
WITH ITS STRONGEST SUPPORT IN THE UPPER JET MORE IN CANADA AND A  
SHEARING AREA OF VORTICITY TO ITS SOUTH THAT TRIES TO EDGE INTO THE  
AREA INTO TUESDAY NIGHT. THE BEST COLUMNAR MOISTURE SWINGS THROUGH  
NORTHERN AND WESTERN AREAS LATE TUESDAY NIGHT INTO EARLY WEDNESDAY  
MORNING. MODELS CURRENTLY ONLY HAVE MID 50S TO LOW 60S DEW POINTS  
MOVING IN DURING THAT TIME, BUT 850 MB DEW POINTS DO SURPASS 10C.  
THE ECMWF HAS MINIMAL MUCAPE TO WORK WITH. THIS ALL SEEMS TO  
INDICATE ISSUES WITH MOISTURE WORKING INTO THE REGION OVERALL AND  
POTENTIALLY SOME ISSUES WITH DRY AIR CHOKING MOISTURE TRANSPORT UP  
AND TO THE SURFACE EVEN WITH A MOISTURE CONNECTION TO THE GULF.  
 
AFTER THE PRIOR WAVE MOVES THROUGH INTO AT LEAST THE FIRST PART OF  
WEDNESDAY, IT APPEARS THERE'S A BIT OF A BREAK IN RAIN UNTIL THE  
WASHED OUT FRONT FROM WEDNESDAY MOVES BACK NORTHWARD AS A WARM FRONT  
FOR THURSDAY. THIS FRONT STALLS OUT ACROSS THE AREA AND SERVES AS A  
FOCUS FOR SHOWERS FROM THURSDAY INTO THE WEEKEND. STORM POTENTIAL  
WILL BE DEPENDENT ON THE EVENTUAL LOCATION OF THE FRONT, AS  
BETTER INSTABILITY COULD STAY SOUTH OF THE AREA. SURFACE DEW  
POINTS REACH 65F THURSDAY AND FRIDAY THE ECMWF HAS GOOD LARGE  
SCALE ASCENT ACROSS THE AREA THURSDAY AM AS WELL AS PARTS OF  
FRIDAY AND SATURDAY. THERE IS STILL PLENTY OF DISAGREEMENT  
BETWEEN WHEN A CUTOFF LOW IN THE SOUTHWEST MAKES IT UP HERE, BUT  
SOMETIME BETWEEN FRIDAY AND SATURDAY LOOKS LIKELY. IF THERE WAS  
ONE DAY THAT LOOKS LIKE THERE COULD BE SOME STRONGER  
THUNDERSTORMS, IT'S SATURDAY, BUT WE HAVE A LONG TIME TO GET  
THERE YET.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z SUNDAY/
 
 
ISSUED AT 606 AM EDT SAT SEP 26 2026  
 
SURFACE HIGH PRESSURE TO THE NORTH OF THE AREA KEEPS DRY AIR  
ENTRENCHED OVERHEAD AND HELPS THE AREA RETAIN VFR CONDITIONS  
THROUGH THE PERIOD. WINDS STAY OUT OF THE NORTHEAST AND WILL BE  
LIGHT, STAYING LESS THAN 10 KTS SUSTAINED.  
 

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

 
 

 
 
DISCUSSION...ROLLER  
AVIATION...ROLLER  
 
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