819  
FXUS63 KIWX 082323  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
723 PM EDT WED OCT 8 2025  
   
KEY MESSAGES  
 
- AREAS OF FROST THURSDAY AND FRIDAY MORNING.  
 
- TEMPERATURES WARM BACK TO NEAR OR SLIGHTLY ABOVE NORMAL THIS  
WEEKEND INTO NEXT WEEK.  
 
- RAIN WILL REMAIN SPARSE THROUGH THE NEXT 7 DAYS.  
 
 
   
DISCUSSION  
 
ISSUED AT 216 PM EDT WED OCT 8 2025  
 
HIGH PRESSURE OVER WI THIS AFTERNOON SHIFTS EAST THROUGH TIME,  
BRINGING BACK-TO-BACK CRISP AND FROSTY NIGHTS. WITH LOW PRESSURE  
WELL OFF THE NORTHEAST US COAST, CONFIDENCE IS HIGH IN LIGHT WIND  
OVERNIGHT AND CLEAR SKIES. CURRENT FORECAST LOWS ARE ON THE  
COLDER SIDE OF GUIDANCE, WHICH, GIVEN THIS PATTERN CHANGE,  
PLACEMENT OF THE SURFACE HIGH, AND 850MB TEMPERATURES OF 2C TO  
4C, AIMING TO THE COLD SIDE OF GUIDANCE APPEARS WARRANTED. AS A  
RESULT, HAVE OPTED FOR AN AREA-WIDE FROST ADVISORY. THE ARGUMENT  
COULD BE MADE THAT SOME NORTHWEST OH COUNTIES AND INDIANA  
COUNTIES SOUTH OF US 24 MAY NOT HAVE A LONG ENOUGH DURATION OF  
36F, BUT THIS SEEMS TO BE SPLITTING HAIRS IN THE GRAND SCHEME.  
ADVISORIES WILL NEED TO BE CONSIDERED AGAIN FOR FRIDAY MORNING.  
 
RETURN, SOUTHERLY FLOW, TAKES PLACE FRIDAY BUT IS AT ODDS WITH  
FALLING HEIGHTS ALOFT AHEAD OF AN INCOMING LOW. THIS LOW DEEPENS AND  
RACES ACROSS MICHIGAN SATURDAY. THIS UPPER-LEVEL LOW IS MOISTURE  
STARVED GIVEN ITS CONTINENTAL POLAR SOURCE REGION. HOWEVER,  
GUIDANCE HAS BEEN TRENDING WETTER THESE PAST COUPLE OF DAYS AS  
SOLUTIONS HAVE BECOME MORE AMPLIFIED. NOT A WASHOUT FOR OUR AREA,  
BUT AT LEAST NORTHERN POTIONS OF THE FORECAST AREA HAVE A 20% CHANCE  
OF SHOWERS FRIDAY NIGHT AND SATURDAY.  
 
UPPER-LEVEL RIDGING RESUMES IN THE WAKE OF THIS LOW. HIGH  
TEMPERATURES WILL RETURN TO THE 70S. PROSPECTS FOR RAIN NEXT WEEK  
REMAIN MURKY AND DEPENDENT ON THE PLACEMENT AND MAGNITUDE OF THIS  
UPPER-LEVEL RIDGE TAKING SHAPE. IN THE MEANTIME, IN-HOUSE BLEND HAS  
SPURIOUS SLIGHT-CHANCE POPS NEAR THE LAKE.  
 
 
   
AVIATION /18Z TAFS THROUGH 18Z THURSDAY/  
 
ISSUED AT 1229 PM EDT WED OCT 8 2025  
 
AS HIGH PRESSURE SLIDES BY TO THE NORTH, NORTH WINDS AND CLEAR SKIES  
WILL PROVIDE VFR CONDITIONS THROUGH THE TAF PERIOD. LAV GUIDANCE  
HAS CROSS-OVER TEMPERATURES THAT ARE NOT CONDUCIVE TO CREATING  
FOG. SLIGHTLY LOWER TEMPERATURES, AS CAN HAPPEN IN THESE  
RADIATIONAL COOLING SETUPS, COULD CREATE FOG, BUT IT WOULD  
LIKELY ONLY CREATE SHALLOW FOG AT BEST GIVEN FORECAST SOUNDING  
SHAPE. AS SUCH WILL KEEP THESE TAFS IN VFR. CLEAR SKIES AND  
MIXING WOULD NORMALLY CREATE A GUSTY DAY, BUT A WEAK GRADIENT  
UNDERNEATH THE SURFACE HIGH WEAKENS THE LOW LEVEL JET SO  
SUSTAINED WINDS SHOULD STAY BELOW 10 KTS. NORTH WINDS BECOME  
MORE EASTERLY LATE TONIGHT OR EARLY THURSDAY MORNING.  
 
 
   
IWX WATCHES/WARNINGS/ADVISORIES  
 
IN...FROST ADVISORY FROM 4 AM EDT /3 AM CDT/ TO 9 AM EDT /8 AM CDT/  
THURSDAY FOR INZ005>009-012>015-017-018-020-022>027-  
032>034-103-104-116-203-204-216.  
OH...FROST ADVISORY FROM 4 AM TO 9 AM EDT THURSDAY FOR OHZ001-002-  
004-005-015-016-024-025.  
MI...FROST ADVISORY FROM 4 AM TO 9 AM EDT THURSDAY FOR MIZ078>081-  
177-277.  
MARINE...NONE.  
 
 
 
 
 
DISCUSSION...BROWN  
AVIATION...ROLLER  
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