503  
FXUS63 KIWX 152238  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
638 PM EDT SUN JUN 15 2025  
   
KEY MESSAGES
 
 
- WARMING TREND CONTINUES INTO MONDAY AND TUESDAY. PEAK AFTERNOON  
HEAT INDICES NEAR 90 DEGREES BY TUESDAY.  
 
- THERE IS A LOW (20-40%) CHANCE FOR WIDELY SCATTERED SHOWERS  
AND STORMS ALONG AND SOUTHEAST OF THE US 24 CORRIDOR MONDAY  
AFTERNOON-NIGHT.  
 
- MULTIPLE ROUNDS OF SHOWERS AND STORMS LIKELY LATE TUESDAY  
NIGHT THROUGH WEDNESDAY NIGHT. THERE IS THE POTENTIAL FOR  
SEVERE STORMS AND HEAVY RAINFALL ON WEDNESDAY.  
 
- THE WARMEST AND MOST HUMID AIR OF THE SEASON ARRIVES NEXT  
WEEKEND.  
 

 
   
DISCUSSION
 
 
ISSUED AT 233 PM EDT SUN JUN 15 2025  
 
THE WESTERN FRINGES OF LOW LEVEL RIDGING WILL MAINTAIN DRY  
CONDITIONS LOCALLY INTO TONIGHT AND MONDAY MORNING AS AN INSTABILITY  
AXIS REMAINS OFF TO THE SOUTH AND WEST. A WEAK SFC TROUGH AND DEEPER  
MOISTURE DOES LIFT NORTH INTO AREAS MAINLY SOUTH OF THE US 24  
CORRIDOR MONDAY AFTERNOON-NIGHT IN RESPONSE TO A CONVECTIVELY  
INDUCED SHORTWAVE (NOW OVER FAR SOUTHWEST MISSOURI) PROPAGATING EAST-  
NORTHEAST THROUGH THE OHIO VALLEY. THIS MAY BE ENOUGH TO GENERATE  
WIDELY SCATTERED SHOWERS/STORMS IN OUR SOUTHEAST WITH A SLIGHT  
EXPANSION/INCREASE TO POPS.  
 
A WARMER, MORE HUMID, AIRMASS WILL OVERSPREAD THE ENTIRE AREA  
TUESDAY INTO WEDNESDAY. THE BETTER LOW LEVEL RETURN FLOW AND  
PRIMARY MUCAPE AXIS LIKELY REMAINS OFF TO THE WEST FOR MUCH OF  
TUESDAY IN BETWEEN SHORTWAVES FOR ONLY A LOW CHANCE POP (20-30%).  
 
MULTIPLE ROUNDS OF MORE ORGANIZED CONVECTION STILL LOOKING LIKELY  
LATE TUESDAY NIGHT THROUGH WEDNESDAY EVENING AS A MORE PRONOUNCED  
SHORTWAVE AND ASSOCIATED FRONTAL WAVE EJECTS EAST-NORTHEAST FROM THE  
CENTRAL PLAINS TO THE LOWER GREAT LAKES. INCREASING LOW-MID LEVEL  
SOUTHWEST FLOW PRECEDING THE WAVE PROVIDES IMPRESSIVE MOISTURE  
TRANSPORT (~70F SFC DEWPOINTS AND 1.80" PLUS PWATS) HINTING AT A  
HEAVY RAIN/FLOODING THREAT, AND POTENTIALLY AN ORGANIZED SEVERE RISK  
BY WEDNESDAY AFTERNOON-EVENING. THE EVOLUTION OF A POTENTIAL MORNING  
CONVECTIVE COMPLEX, AND WHERE THE PRIMARY MCS OUTFLOW/COLD POOL  
BOUNDARY LIES OUT BY PEAK HEATING WILL DICTATE WHERE THIS SEVERE  
RISK MATERIALIZES DURING THE PM HOURS ON WEDNESDAY. CONFIDENCE IS  
OBVIOUSLY LOW REGARDING THESE MESOSCALE DETAILS 4 DAYS OUT, BUT  
DEFINITELY SOMETHING TO MONITOR IN THE COMING DAYS.  
 
THEREAFTER, EXPECT A BRIEF COOLDOWN POST-FRONTAL INTO THURSDAY, WITH  
THE WARMEST AND MOST HUMID AIR OF THE SEASON ARRIVING BY NEXT  
WEEKEND UNDER AN UPPER LEVEL RIDGE EXPANDING NORTHEAST INTO THE  
GREAT LAKES.  
 

 
   
AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
 
 
ISSUED AT 634 PM EDT SUN JUN 15 2025  
 
HIGH PRESSURE WILL KEEP VFR TAF FORECAST THROUGH THE PERIOD FOR  
BOTH TAF SITES. CONTINUED LIGHT NORTHEASTERLY WINDS LESS THAN  
10 KTS WILL VEER MORE SOUTHEASTERLY AFTER 18Z MON.  
 

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

 
 

 
 
DISCUSSION...STEINWEDEL  
AVIATION...ANDERSEN  
 
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