244  
FXUS63 KIND 221734  
AFDIND  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE INDIANAPOLIS IN  
134 PM EDT FRI MAY 22 2026  
   
KEY MESSAGES
 
 
- RAIN SPREADS NORTH ACROSS MUCH OF CENTRAL INDIANA TODAY WITH  
CONTINUED BELOW NORMAL TEMPERATURES. SOME POTENTIAL FOR  
LOCALIZED FLOODING IN SE PORTIONS OF CENTRAL INDIANA THIS  
EVENING AND TONIGHT.  
 
 
- RAIN CHANCES CONTINUE THROUGH THE HOLIDAY WEEKEND INTO NEXT WEEK,  
BUT TEMPERATURES WILL BECOME ABOVE NORMAL FOR MUCH OF THE PERIOD.  
 

 
   
DISCUSSION (THIS EVENING THROUGH FRIDAY)
 
 
ISSUED AT 128 PM EDT FRI MAY 22 2026  
 
TODAY AND TOMORROW...  
 
FOR THIS WEEKEND, CENTRAL INDIANA WILL BE WITHIN AN ACTIVE  
PORTION OF A SUBTROPICAL JET STREAK, OF WHICH WILL AID IN THE  
DEVELOPMENT OF SHORTWAVES AND THEREFOR MULTIPLE CHANCES FOR  
RAINFALL. THE FIRST OF WHICH IS PASSING THROUGH TODAY AND TONIGHT.  
THIS PARTICULAR SHORTWAVE IS EJECTING OUT OF THE GULF WITH  
ABUNDANT MOISTURE THROUGHOUT. THE ENHANCED DIABATIC PROCESSES OF  
THIS GULF LOW WILL AID IN LOW LEVEL PRESSURE DEPLETION OVER THE  
NEXT 12-24 HOURS, RESULTING IN A MORE MATURE SURFACE LOW LATE  
TODAY AND TONIGHT.  
 
INITIAL RAINFALL IS EXPECTED TO BE ASSOCIATED WITH WEAK FRONTAL  
CONVERGENCE IN THE 850-700MB LAYER AS DRY NE FLOW INTERACTS WITH  
VERY MOIST SE FLOW OVER THE OHIO VALLEY. CURRENT RADAR AND IR  
IMAGERY SHOWCASE THIS WELL WITH WIDESPREAD RAIN ALONG THE OH/IN  
BORDER QUICKLY SURGING NORTHWARD. THIS RAIN IS EXPECTED TO BE IN  
THE INDIANAPOLIS AREA AROUND 2PM FRIDAY AFTERNOON. CONSISTENT  
LIGHT TO MODERATE RAINFALL IS EXPECTED TO BE THE NORM FOR MOST OF  
THE AFTERNOON AND EARLY EVENING OVER THE SE HALF OF CENRAL INDIANA  
WITH THE ONE EXCEPTION BEING A LOW CHANCE FOR THERMODYNAMICALLY  
ENFORCED CONVECTION OVER FAR SOUTHERN CENTRAL INDIANA. HOWEVER,  
LATE THIS EVENING AND TONIGHT, SLANTWISE INSTABILITY IN THE FRONT  
RIGHT QUADRANT OF THE ADVANCING LOW WILL AID UPWARD LIFT, LIKELY  
PROMOTING A PERIOD OF MODERATE TO HEAVY RAINFALL AND ISOLATED  
LIGHTNING PRODUCTION.  
 
WHEN ALL IS SAID AND DONE, TOTAL RAIN AMOUNTS WILL VARY ACROSS THE  
REGION, BUT GENERALLY THOSE S/E OF I-69 ARE EXPECTED TO GET 0.5-1.5"  
WITH LESSER AMOUNTS TO THE N/W. THE CSI BANDING POTENTIAL OVERNIGHT  
COULD LEAD TO NARROW CORRIDORS OF 2-3 INCHES, OF WHICH WILL CREATE  
A LOW END FLOODING THREAT GIVEN ALREADY SATURATED SOILS FROM  
PRIOR RAINFALL.  
 
A QUASI STATIONARY BOUNDARY WILL LINGER NORTH OF CENTRAL INDIANA  
FOLLOWING THE PASSAGE OF THE WAVE. ALONG AND SOUTH OF THIS BOUNDARY,  
THERE WILL BE ENOUGH MOISTURE AND INSTABILITY FOR ISOLATED  
CONVECTION TO OCCUR, BUT THE ONLY FORCING WILL LIKELY BE  
ASSOCIATED WITH MICROSCALE FLUCTUATIONS AND WEAK SYNOPTIC LIFT  
WITHIN THE ENTRANCE REGION OF THE SUBTROPICAL JET. THE CURRENT  
EXPECTATION IS FOR A LARGE MAJORITY OF CENTRAL INDIANA TO REMAIN  
DRY TOMORROW, WITH A FEW AREAS SEEING A BRIEF SHOWER OR STORM IN  
THE MORNING TO EARLY AFTERNOON.  
 
SUNDAY...  
 
THE NEXT SHORTWAVE WILL ARRIVE FROM THE WEST LATE SATURDAY NIGHT  
THROUGH SUNDAY. MOISTURE WITH THIS WAVE PASSAGE WILL NOT BE AS  
ABUNDANT, BUT WITH ANTECEDENT DEW POINTS ALREADY IN THE MID TO UPPER  
60S, THERE SHOULD BE ENOUGH INSTABILITY FOR CONVECTIVE INITIATION TO  
OCCUR AS THE WAVE PASSES THROUGH. HIGH RESOLUTION GUIDANCE IS MIXED  
ON WAVE TIMING AS OF 12Z FRIDAY. SPECIFICALLY FOR INDIANAPOLIS THERE  
IS A RANGE FROM 15-18Z START TIME AND A 20-00Z END TIME FOR STORM  
CHANCES. GIVEN WEAK SHEAR WITHIN THE PASSING WAVE ALONG WITH 500-  
1000 J/KG OF SBCAPE, ISOLATED STRONG TO SEVERE THUNDERSTORMS CAN  
ALSO NOT BE RULED OUT DURING THIS TIMEFRAME. AFTER THE WAVE PASSES  
THROUGH SUNDAY LATE AFTERNOON/EVENING MODEST SUBSIDENCE SHOULD  
QUICKLY REDUCE RAIN CHANCES WITH DRY WEATHER EXPECTED SUNDAY EVENING  
AND NIGHT.  
 
TEMPERATURES WILL LIKELY BE SLIGHTLY WARMER SUNDAY WITH WEAK  
SOUTHERLY FLOW RETURNING, BUT WILL GREATLY DEPEND ON WHERE  
CONVECTION AND RELATED CLOUD COVER OCCURS. GENERAL EXPECTATION IS  
FOR AFTERNOON HIGHS IN THE UPPER 70S.  
 
MEMORIAL DAY ONWARD...  
 
FOLLOWING SUNDAY'S WAVE PASSAGE, AMPLIFIED RIDGING WILL START TO  
BUILD OVER THE SOUTHERN APPALACHIA TO THE OHIO VALLEY REGIONS  
DECREASING UPPER LEVEL FORCING. HOWEVER, IN THE LOWER LEVELS, A  
STAGNANT BOUNDARY IS EXPECTED TO DEVELOP NEAR THE OHIO RIVER. WEAK  
FORCING AND REMNANT MOISTURE ALONG THE BOUNDARY WILL LIKELY INDUCE A  
SCATTERED SHOWERS MONDAY THROUGH TUESDAY OVER THIS SAME AREA. AREAS  
TO THE NORTH (A MAJORITY OF CENTRAL INDIANA) ARE EXPECTED REMAIN  
DRY. TEMPERATURES LOOK TO BE SLIGHTLY ABOVE NORMAL WITH SOME  
INFLUENCE FROM THE RIDGING TO THE EAST EXPECTED.  
 
FORECAST CONFIDENCE DECREASES SIGNIFICANTLY WEDNESDAY ONWARD AS  
ENSEMBLES INTRODUCE ANOTHER WAVE ENTERING THE REGION FROM THE  
WEST. GENERALLY, THIS WILL INCREASE POPS FOR WEDNESDAY, BUT  
SPECIFICS FOR THIS WAVE PASSAGE ARE STILL HIGHLY VARIABLE.  
 

 
   
AVIATION (18Z TAF ISSUANCE)
 
 
ISSUED AT 128 PM EDT FRI MAY 22 2026  
 
IMPACTS:  
 
- CONDITIONS DETERIORATE TO IFR AT MOST SITES THIS AFTERNOON  
- SHOWERS SPREAD NORTH THIS AFTERNOON  
- WIND GUSTS AROUND 20KT AT KLAF TODAY  
 
DISCUSSION:  
 
MOISTURE WILL CONTINUE TO INCREASE TODAY, WITH GRADUALLY LOWERING  
CEILINGS. AS LOW PRESSURE APPROACHES FROM THE SOUTH THIS AFTERNOON,  
SHOWERS WILL SPREAD NORTH ACROSS THE SITES. BY 21Z, IFR CEILINGS AND  
SHOWERS WILL BE COMMON. KLAF WILL TAKE LONGER TO REACH IFR AND WILL  
HAVE THE LOWEST CHANCES FOR SHOWERS.  
 
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING, BUT  
COVERAGE WILL BE TOO LOW TO MENTION IN THE TAFS. BEST CHANCES FOR  
THUNDER WILL BE AT KBMG. LOW CEILINGS WILL PERSIST INTO SATURDAY  
MORNING. WINDS WILL STAY EASTERLY THROUGHOUT THE EVENING AND TONIGHT  
BEFORE QUICKLY SWITCHING TO WESTERLY TOMORROW MORNING.  
 

 
   
IND WATCHES/WARNINGS/ADVISORIES
 
 
FLOOD WATCH THROUGH LATE TONIGHT FOR INZ071-072.  
 

 
 

 
 
AVIATION...50/UPDIKE  
DISCUSSION...UPDIKE  
 
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