979  
FXUS63 KIND 160703  
AFDIND  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE INDIANAPOLIS IN  
303 AM EDT SUN AUG 16 2026  
   
KEY MESSAGES  
 
- STORM THREAT CONTINUES THROUGH TONIGHT, WITH LOCALLY DAMAGING  
WINDS, HEAVY RAIN, AND RAPID ONSET FLASH FLOODING REMAINING  
POSSIBLE  
 
- HEAT INDEX VALUES IN EXCESS OF 100 POSSIBLE TODAY IN SOUTHERN  
PORTIONS OF CENTRAL INDIANA  
 
- DRY AND MILDER WEATHER EARLY IN THE WORK WEEK  
 
- ADDITIONAL STORMS POSSIBLE WEDNESDAY  
 
 
   
DISCUSSION (TODAY THROUGH SATURDAY)  
 
ISSUED AT 303 AM EDT SUN AUG 16 2026  
 
THROUGH TONIGHT...  
 
ONE OR MORE UPPER LEVEL WAVES, AT LEAST PARTIALLY CONVECTIVELY-  
ENHANCED, WILL TRAVERSE THE AREA THIS MORNING INTO TONIGHT, WITH  
ATTENDANT THREATS FOR ADDITIONAL SHOWERS AND THUNDERSTORMS. MODEST  
BUT SUFFICIENT DEEP LAYER SHEAR WILL REMAIN IN PLACE, ALONG WITH  
AMPLE INSTABILITY IN THE CONTINUED WARM AND VERY MOIST ENVIRONMENT.  
AREAS OF LOW LEVEL CONVERGENCE ASSOCIATED BOTH WITH SURFACE  
BOUNDARIES AND REMNANT CONVECTIVE OUTFLOWS WILL SERVE AS FOCI FOR  
DEVELOPMENT, BUT GIVEN THE COMPLEX SITUATION AND CAM STRUGGLES WITH  
PLACEMENT AND CONSISTENCY RUN-TO-RUN, CONFIDENCE IS LOWERED.  
LOCALIZED DAMAGING WIND GUSTS WILL REMAIN THE PRIMARY SEVERE THREAT.  
 
NEEDLESS TO SAY, FLASH FLOOD CONCERNS WILL REMAIN THE MOST PRESSING  
WORRY, HOWEVER. HREF LOCAL PROBABILITY MATCHED MEANS SUGGEST A  
THREAT FOR UP TO A 1-2+ INCHES OF RAIN WITH THE MOST INTENSE STORMS,  
WHICH WILL CONTINUE TO POSE A EXTREMELY RAPID ONSET FLASH FLOOD  
THREAT, THOUGH THERE IS SOME GUIDANCE SUGGESTION THAT THE HEAVIER  
RAINFALL THREAT MAY BE MORE CENTRAL AND SOUTH, WHICH, WHILE STILL  
QUITE WET, IS NOT QUITE IN AS ROUGH A SHAPE AS AREAS FROM INDY METRO  
NORTH AND NORTHEAST.  
 
MONDAY AND TUESDAY...  
 
AN AREA OF SURFACE HIGH PRESSURE WILL MERCIFULLY BRING AT LEAST A  
TEMPORARY END TO THE REPEATED ROUNDS OF THUNDERSTORMS EARLY IN THE  
WEEK, WITH DRY WEATHER AND NEAR NORMAL TEMPERATURES LIKELY EARLY  
MONDAY INTO TUESDAY.  
 
TUESDAY NIGHT INTO WEDNESDAY NIGHT...  
 
UNFORTUNATELY, AN ADDITIONAL ROUND OF THUNDERSTORMS APPEARS LIKELY  
LATE TUESDAY NIGHT INTO WEDNESDAY NIGHT AS ANOTHER COLD FRONT AND  
UPPER LEVEL WAVE ACCOMPANYING A STRONG JET STREAK ALOFT PASSES  
THROUGH THE REGION. PLENTIFUL MOISTURE WILL BE AVAILABLE, THOUGH  
PRECIPITABLE WATER VALUES MAY BE SLIGHTLY MORE MODEST (70-80TH  
PERCENTILE CLIMATOLOGICALLY). HOWEVER, SOMEWHAT STRONGER DEEP LAYER  
SHEAR MAY BE AVAILABLE. ANOTHER ROUND OF SEVERE STORMS WILL  
CERTAINLY BE POSSIBLE, THOUGH PREDICTABILITY IS GREATLY LIMITED  
GIVEN THE SENSITIVITY TO PRIOR ROUNDS OF STORMS AND MODEL  
INCONSISTENCIES 4 DAYS OUT.  
 
THAT SAID, EVEN WITH A COUPLE OF DAYS TO DRY OUT, FLASH FLOOD  
VULNERABILITY WILL REMAIN QUITE HIGH IN THE FACE OF ANY ADDITIONAL  
CONVECTIVE RAINFALL GIVEN THE EXTREME ANTECEDENT CONDITIONS, AND WE  
WILL NEED TO REMAIN VIGILANT THROUGH AT LEAST MID WEEK FOR THESE  
CONCERNS.  
 
THURSDAY ONWARD...  
 
AMPLIFICATION OF THE UPPER RIDGE OVER THE WESTERN CONUS AND  
SOUTHWARD DISPLACEMENT OF BOTH THE FRONTAL ZONE AND DEEPER MOISTURE  
BY SURFACE HIGH PRESSURE AND UPPER LEVEL TROUGHING SUGGEST MILDER  
TEMPERATURES AND MOSTLY DRY CONDITIONS LATE WEEK AND INTO THE  
WEEKEND, THOUGH SOME SLIGHT CHANCES FOR SHOWERS OR STORMS MAY LINGER  
ACROSS THE SOUTHERN PORTIONS OF CENTRAL INDIANA. IT WILL TAKE QUITE  
SOME TIME FOR ANTECEDENT CONDITIONS TO SIGNIFICANTLY IMPROVE,  
UNFORTUNATELY, AND ANY ADDITIONAL CONVECTIVE RAINFALL WITH PERIODIC  
FRONTAL PASSAGES OR UPPER LEVEL WAVES IN THE BROADER CYCLONIC FLOW  
NEXT WEEKEND AND INTO THE FOLLOWING WEEK WILL POSE AT LEAST MODEST  
FLASH FLOOD THREATS.  
 
 
   
AVIATION (06Z TAF ISSUANCE)  
 
ISSUED AT 128 AM EDT SUN AUG 16 2026  
 
IMPACTS:  
 
- THREAT FOR SHOWERS AND STORMS AGAIN AT TIMES THROUGH MID AFTERNOON  
 
- PATCHY MVFR FOG AT SOME SITES THROUGH DAYBREAK  
 
DISCUSSION:  
 
THE CONTINUED PRESENCE OF A VERY MOIST AND HUMID AIRMASS WILL  
PROMOTE PATCHY MVFR FOG THROUGH DAYBREAK AT ONE OR MORE OF THE  
OUTLYING SITES.  
 
ADDITIONALLY, ISOLATED TO WIDELY SCATTERED SHOWERS AND STORMS ARE  
DEVELOPING NEAR IND, AND ADDITIONAL ACTIVITY WILL LIKELY MOVE INTO  
THE AREA LATER THIS MORNING INTO THE EARLY TO MID AFTERNOON HOURS.  
WILL CARRY SHOWERS AND PROB30 GROUPS AT EACH SITE DURING THE MOST  
FAVORED TIME FRAME.  
 
WINDS WILL GENERALLY BE LIGHT AND VARIABLE TO CALM OVERNIGHT,  
BECOMING MORE WESTERLY WITH TIME AS HIGH AS 8-12KT.  
 
 
   
IND WATCHES/WARNINGS/ADVISORIES  
 
FLOOD WATCH UNTIL NOON EDT TODAY FOR INZ021-028>031-035>049-  
051>057-065.  
 
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR INZ060>063-067>071.  
 
 
 
 
 
AVIATION...NIELD  
DISCUSSION...NIELD  
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