072  
FXUS63 KIND 220554  
AFDIND  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE INDIANAPOLIS IN  
154 AM EDT TUE SEP 22 2026  
   
KEY MESSAGES
 
 
- MAINLY CLOUDY AND COOL THROUGH MIDWEEK  
 
- DRY AND SEASONABLE LATE WEEK INTO THE WEEKEND WITH GRADUALLY  
WARMING TEMPERATURES  
 

 
   
FORECAST UPDATE
 
 
ISSUED AT 912 PM EDT MON SEP 21 2026  
 
SURFACE ANALYSIS THIS EVENING SHOWS STRONG, CANADIAN HIGH PRESSURE  
IN PLACE OVER ONTARIO AND QUEBEC. THIS HIGH WAS INFLUENCING THE  
WEATHER ACROSS THE GREAT LAKES AND SOUTH TO THE OHIO RIVER. COOL AND  
DRY NORTHEASTERLY FLOW WAS IN PLACE ACROSS INDIANA, ALONG WITH A  
MODERATE PRESSURE GRADIENT. GOES19 SHOWS ABUNDANT CLOUD COVER ACROSS  
CENTRAL INDIANA AND THE REGION. THE HIGH TO THE NORTH WAS RESULTING  
IN A COOL NW DIRTY FLOW.  
 
OVERNIGHT, VERY LITTLE CHANGE IN THE OVERALL FORECAST. CLOUDS WILL  
REMAIN ACROSS THE AREA AMID THE CONTINUED EASTERLY FLOW. FORECAST  
SOUNDINGS CONTINUE TO INDICATE SATURATION WITHIN THE LOWER LEVELS  
WITH A TRAPPING INVERSION ALOFT. THUS CLOUDY SKIES WILL PERSIST  
THROUGH THE NIGHT. THE CLOUDS AND WINDS WILL KEEP TEMPERATURES FROM  
FALLING TOO MUCH AS THEY REACH THE MID AND UPPER 50S.  
 

 
   
DISCUSSION (THIS EVENING THROUGH MONDAY)
 
 
ISSUED AT 220 PM EDT MON SEP 21 2026  
 
MUCH COOLER AIR HAS OVERSPREAD THE REGION IN THE WAKE OF THE  
FRONTAL PASSAGE LATE SUNDAY. CLOUDY AND BREEZY CONDITIONS ARE  
EXPECTED THROUGH WEDNESDAY AS AN UPPER LOW MOVES SLOWLY THROUGH THE  
AREA. THIS FEATURE WILL CUTOFF OVER THE MID ATLANTIC BY LATE  
WEEK...WITH MUCH DRIER AIR BEING PULLED SOUTH INTO THE OHIO VALLEY  
THROUGH THE WEEKEND.  
 
REST OF TODAY THROUGH WEDNESDAY NIGHT  
 
IN THE WAKE OF THE MORNING RAIN...A DAMP AND DREARY AIRMASS REMAINS  
ACROSS CENTRAL INDIANA UNDER A THICK STRATUS DECK AND WITH BREEZY  
NORTHEAST WINDS. 18Z TEMPERATURES WERE MUCH COOLER THAN WHAT HAS  
BEEN EXPERIENCED OVER THE LAST SEVERAL DAYS WITH MUCH OF CENTRAL  
INDIANA IN THE 60S.  
 
THERE REMAIN A FEW LIGHT SHOWERS OR SPRINKLES OVER THE SOUTHEAST  
HALF OF THE FORECAST AREA BUT THE OVERALL TREND SINCE THE MORNING  
HAS BEEN FOR RAINFALL COVERAGE TO DECREASE EXTENSIVELY AS THE  
FRONTAL BOUNDARY THAT MOVED THROUGH THE AREA SUNDAY AFTERNOON AND  
EVENING HAS NOW MOVED WELL SOUTH INTO THE TENNESSEE VALLEY.A FEW  
LIGHT SHOWERS REMAIN POSSIBLE FOR THE NEXT FEW HOURS BEFORE  
DEPARTING. ABUNDANT MOISTURE PERSISTS THROUGH THE BOUNDARY LAYER  
TRAPPED BENEATH A STOUT INVERSION. MODEL SOUNDINGS SHOW THE  
INVERSION WEAKENING SLIGHTLY THIS EVENING WHICH MAY BE JUST ENOUGH  
TO ALLOW FOR A BRIEF PERIOD WITH BREAKS IN THE STRATUS DECK. AS THE  
INVERSION STRENGTHENS OVERNIGHT HOWEVER...EXPECT THE STRATUS DECK TO  
THICKEN BACK UP WITH CEILINGS LOWERING AGAIN INTO TUESDAY MORNING.  
CANNOT ENTIRELY RULE OUT A FEW SPRINKLES TONIGHT BUT LOW CONFIDENCE  
IN THIS OCCURRING.  
 
CLOUDS WILL REMAIN ON TUESDAY AS AN UPPER LOW PIVOTS INTO THE REGION  
FROM THE NORTHWEST. THE UPPER LOW WILL BRING ISOLATED LIGHT SHOWERS  
ACROSS THE FAR NORTHEAST PORTION OF THE FORECAST AREA OTHERWISE  
EXPECT A CONTINUATION OF WEATHER TODAY WITH THICK STRATUS AND COOL  
N/NE FLOW. THE UPPER LOW WILL BE SLOW TO SHIFT EAST OF THE AREA AS  
IT BECOMES CUTOFF FROM THE MEAN FLOW ALOFT WELL TO THE NORTH OF THE  
REGION. THIS WILL KEEP AN ABUNDANCE OF CLOUDS OVER MOST OF THE  
FORECAST AREA THROUGH WEDNESDAY AS WELL WITH AGAIN A LOW CHANCE FOR  
A FEW SHOWERS ACROSS OUR NORTHEAST COUNTIES. MORE SUBSTANTIAL BREAKS  
IN THE CLOUDS SHOULD COME WEDNESDAY NIGHT AS RIDGING ALOFT SLOWLY  
SPREADS INTO THE OHIO VALLEY FROM THE WEST.  
 
TEMPS...HIGHS WILL NOT GET OUT OF THE 60S THIS AFTERNOON FOR MUCH OF  
THE FORECAST AREA...THE COOLEST DAY SINCE MAY 23. EXPECT SIMILAR  
TEMPERATURES BOTH TUESDAY AND WEDNESDAY WITH HIGHS RANGING FROM THE  
MID 60S NORTHEAST TO THE LOWER 70S SOUTHWEST. LOWS WILL BE IN THE  
50S.  
 
THURSDAY THROUGH SUNDAY  
 
THE AFOREMENTIONED UPPER LOW WILL SETTLE OVER THE MID ATLANTIC  
REGION DURING THE SECOND HALF OF THE WEEK. COOL E/NE FLOW AND AT  
LEAST SOME LINGERING CLOUD COVER ON THE BACK SIDE OF THE DEVELOPING  
CUTOFF LOW WILL MAINTAIN BELOW NORMAL TEMPERATURES THURSDAY WITH  
HIGHS RANGING FROM THE UPPER 60S TO THE MID 70S FROM NORTHEAST TO  
SOUTHWEST. RIDGING ALOFT WILL GRADUALLY SHIFT INTO THE OHIO VALLEY  
WITH AN AXIS OF DEEPENING SUBSIDENCE ADVECTING INTO THE REGION FROM  
THE NORTH. UNDER MAINLY CLEAR SKIES...TEMPERATURES WILL RECOVER BACK  
TO LATE SEPTEMBER NORMALS WITH HIGHS WARMING INTO THE MID AND UPPER  
70S BY SUNDAY AND PERHAPS INTO THE LOWER 80S OVER PARTS OF THE  
FORECAST AREA BY MONDAY. THE COOLEST NIGHT SINCE THE SPRING COMES  
FRIDAY NIGHT AS LOWS IN THE MID AND UPPER 40S WILL BE COMMON...WITH  
TEMPERATURES RECOVERING INTO THE 50S FOR LOWS BY THE END OF THE  
WEEKEND.  
 

 
   
AVIATION (06Z TAF ISSUANCE)
 
 
ISSUED AT 154 AM EDT TUE SEP 22 2026  
 
IMPACTS:  
 
- MVFR CEILINGS PERSIST, IFR POSSIBLE THIS EVENING INTO WEDNESDAY.  
- PATCHY DRIZZLE THIS EVENING INTO WEDNESDAY, ISOLATED SHOWERS  
POSSIBLE.  
 
DISCUSSION:  
 
STRONG SURFACE HIGH PRESSURE RESIDES OVER SOUTHEASTERN CANADA,  
PROVIDING A STEADY NORTHEASTERLY BREEZE ACROSS CENTRAL INDIANA.  
WINDS HAVE BEEN BETWEEN 10-15KT FROM LAF TO IND, AND 5-10KT FROM HUF  
TO BMG. LITTLE CHANGE IN WINDS SPEED IS ANTICIPATED THROUGH THE TAF  
PERIOD, WITH ONLY THE PREVAILING DIRECTION BECOMING MORE  
NORTHEASTERLY WITH TIME.  
 
PERIODIC MVFR CEILINGS ARE OCCURRING ACROSS THE REGION AS WELL, WITH  
COVERAGE GRADUALLY EXPANDING. WE CURRENTLY EXPECT THAT STRATUS WILL  
EXPAND UNTIL IT BECOMES AN OVC LAYER THIS MORNING. CEILINGS BETWEEN  
1500-2500FT ARE EXPECTED THROUGH THIS AFTERNOON, LOWERING THIS  
EVENING INTO WEDNESDAY.  
 
AN UPPER-LEVEL LOW IS EXPECTED TO ARRIVE TONIGHT. THIS SHOULD INDUCE  
BROAD CYCLONIC CURVATURE IN THE SURFACE WIND FIELD, ALLOWING CLOUD  
COVER TO THICKEN AND LOWER. IFR CEILINGS ARE POSSIBLE AFTER 00Z,  
BECOMING LIKELY AFTER 06Z. ADDITIONALLY, SUBTLE LIFT MAY ALLOW FOR  
SOME PATCHY DRIZZLE TO DEVELOP OVERNIGHT INTO WEDNESDAY MORNING.  
THIS MAY REDUCE VISIBILITY AT TIMES. A FEW RAIN SHOWERS CANNOT BE  
RULED OUT EITHER.  
 

 
   
IND WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
UPDATE...PUMA  
AVIATION...ECKHOFF  
DISCUSSION...RYAN  
 
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