566  
FXUS63 KIND 230159  
AFDIND  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE INDIANAPOLIS IN  
959 PM EDT TUE SEP 22 2026  
   
KEY MESSAGES  
 
- COOLER WEATHER WILL CONTINUE THROUGH THE UPCOMING WEEK, WITH  
AFTERNOON TEMPERATURES STAYING BELOW SEASONAL AVERAGES  
 
- A FEW LIGHT SHOWERS TONIGHT INTO TOMORROW, MAINLY ACROSS EASTERN  
INDIANA  
 
- PERSISTENT MOSTLY CLOUDY SKIES WILL BEGIN TO BREAK TOWARDS FRIDAY  
 
 
   
FORECAST UPDATE  
 
ISSUED AT 958 PM EDT TUE SEP 22 2026  
 
ONLY MINOR ADJUSTMENTS TO HOURLY TEMPERATURES WERE NEEDED, OTHERWISE  
FORECAST IS IN GOOD SHAPE.  
 
LOW CLOUDS AND SOMEWHAT BREEZY CONDITIONS PERSIST ACROSS CENTRAL  
INDIANA AND IS EXPECTED TO CONTINUE INTO TOMORROW. LIGHT DRIZZLE  
WILL BE POSSIBLE THROUGH THE NIGHT, GIVEN HOW LOW CLOUDS ARE, BUT  
THUS FAR ANY DRIZZLE THAT HAS BEEN REPORTED BY PEOPLE HAS BEEN LIGHT  
ENOUGH TO NOT BE PICKED UP BY OBSERVATION INSTRUMENTS OTHER THAN  
VISIBILITY REDUCTIONS.  
 
 
   
DISCUSSION (THIS EVENING THROUGH TUESDAY)  
 
ISSUED AT 202 PM EDT TUE SEP 22 2026  
 
OVERVIEW.  
 
CENTRAL INDIANA IS SET FOR A PROLONGED STRETCH OF COOL,  
DRY AUTUMN WEATHER. HIGH PRESSURE ANCHORED TO THE NORTH AND  
NORTHEAST WILL KEEP A CONTINUOUS SUPPLY OF COOL AIR MOVING INTO THE  
REGION ON NORTHEASTERLY WINDS. PERSISTENT LOW LEVEL MOISTURE  
COMBINED WITH COOLER AIR WILL KEEP SKIES MOSTLY CLOUDY TO CLOUDY  
THROUGH THURSDAY. SKIES WILL THEN CLEAR FRIDAY INTO THE WEEKEND WITH  
A SLIGHT WARMING TREND GOING INTO NEXT WEEK.  
 
TONIGHT THROUGH THURSDAY.  
 
BROAD HIGH PRESSURE CONTINUES TO REMAIN LOCKED IN PLACE ACROSS THE  
GREAT LAKES REGION ALONG WITH LOW PRESSURE TO THE SOUTHEAST ALLOWING  
FOR PERSISTENT NORTHEASTERLY FLOW BOTH AT THE SURFACE AND NEAR  
SURFACE. THIS IS HELPING TO KEEP WIDESPREAD CLOUD COVER IN PLACE  
ACROSS MUCH OF CENTRAL INDIANA ALONG WITH KEEPING TEMPERATURES  
SLIGHTLY BELOW NORMAL. A WEAK SHORTWAVE WILL PUSH SOUTHEAST ACROSS  
IOWA TONIGHT INTO TOMORROW WHICH WILL INTERACT WITH A REMNANT VORT  
MAX ACROSS OHIO DURING THE DAYTIME HOURS TO BRING FEW LIGHT RAIN  
SHOWERS TO CENTRAL INDIANA, MAINLY ACROSS THE EASTERN COUNTIES.  
BEYOND THOSE LOW CHANCES, DRY WEATHER IS EXPECTED THROUGH THE  
REMAINDER OF THE 7 DAY FORECAST WITH A FAIRLY STEADY-STATE WEATHER  
PATTERN CONTINUING INTO THURSDAY.  
 
FRIDAY THROUGH TUESDAY.  
 
INCREASING SUBSIDENCE ALOFT ALONG WITH WEAK UPPER LEVEL FLOW WILL  
BEGIN TO BREAK DOWN THE CLOUD COVER FRIDAY INTO THE WEEKEND WILL  
HELP TO BRING TEMPERATURES CLOSER TO NORMAL FOR THIS TIME OF THE  
YEAR. MIN RH VALUES WILL DROP BELOW 40 PERCENT ACROSS SOUTH CENTRAL  
INDIANA WHICH COMBINED WITH THE DRIER CONDITIONS OF LATE, MAY NEED  
TO BE MONITORED FOR A LOW-END FIRE DANGER. NEAR CALM WINDS WILL HELP  
TO LIMIT THAT THREAT.  
 
LOOKING FURTHER INTO EARLY NEXT WEEK, TEMPERATURES IN THE LOWER 80S  
LOOK TO RETURN AS THE SURFACE FLOW GRADUALLY GAINS A MORE SOUTHERLY  
COMPONENT ALONG WITH GRADUALLY INCREASING RAIN CHANCES TOWARDS LATE  
TUESDAY AHEAD OF THE NEXT SYSTEM.  
 
 
   
AVIATION (00Z TAF ISSUANCE)  
 
ISSUED AT 750 PM EDT TUE SEP 22 2026  
 
IMPACTS:  
 
-MVFR TO IFR CIGS THROUGH THE TAF PERIOD  
-LOW CHANCE FOR LIGHT RAIN LATE TONIGHT AND TOMORROW  
 
DISCUSSION:  
 
CIGS ARE EXPECTED TO REMAIN MVFR OR WORSE THROUGH THE TAF PERIOD  
WITH LEVELS GENERALLY AROUND 015-020 THROUGH THE REMAINDER OF THE  
DAY TODAY. HIGH IFR AROUND 007 WILL BE POSSIBLE DURING THE  
OVERNIGHT, MAINLY FROM 06Z TO 12Z WITH CIGS GENERALLY AROUND 015  
OTHERWISE. THERE MAY BE SOME DRIZZLE TONIGHT BUT WINDS SHOULD REMAIN  
STRONG ENOUGH TO LIMIT COVERAGE. BETTER CHANCES FOR RAIN ARRIVE  
TOMORROW AFTERNOON, MAINLY AT IND. WINDS WILL GENERALLY REMAIN  
NORTHEASTERLY AT 7-12KT THROUGH THE TAF PERIOD.  
 
 
   
IND WATCHES/WARNINGS/ADVISORIES  
 
NONE.  
 
 
 
 
UPDATE...KF  
AVIATION...KF  
DISCUSSION...WHITE  
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