202  
FXUS63 KIWX 021736  
AFDIWX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NORTHERN INDIANA  
1236 PM EST TUE DEC 2 2025  
   
KEY MESSAGES
 
 
- SOME LAKE EFFECT SNOW SHOWERS THROUGH EARLY AFTERNOON, BUT  
ADDITIONAL SNOW ACCUMULATIONS SHOULD BE LIGHT.  
 
- A STRONG COLD FRONT PUSHES ACROSS THE AREA ON WEDNESDAY AND  
WILL LIKELY BE ACCOMPANIED BY SOME LIGHT SNOW ACCUMULATIONS OF  
AROUND AN INCH.  
 
- MUCH COLDER AIR MOVES IN FOR MIDDLE OF THE WEEK WITH LOWS NEAR  
0 BY THURSDAY NIGHT AND WIND CHILLS AS COLD AS 10 BELOW. SOME  
MODERATION IN TEMPERATURES FOR THE WEEKEND, BUT STILL BELOW  
NORMAL.  
 

 
   
DISCUSSION
 
 
ISSUED AT 352 AM EST TUE DEC 2 2025  
 
FOR TONIGHT CENTER OF LOW LEVEL ANTICYCLONE WILL TRACK OF THE AREA  
WITH RETURN SOUTHERLY FLOW DEVELOPING OVERNIGHT. SOME HIRES GUIDANCE  
IS PICKING UP ON A FOG POTENTIAL IN THIS SETUP WITH RETURN FLOW OVER  
FRESH SNOWPACK. IF LOW CLOUDS CAN SCATTER THIS EVENING, RADIATIVE  
PROCESSES MAY HELP FOG FORM INITIALLY ALSO. HOWEVER, SOME POTENTIAL  
WITH STRONG LINGERING LOW LEVEL INVERSION THAT LOW CLOUDS COULD  
LINGER OR RE-FORM. THIS APPEARS TO BE A MUDDLED COMBINATION OF  
RADIATIVE/ADVECTIVE PROCESSES OVER TIME TONIGHT, BUT HAVE INCLUDED  
MENTION OF SOME PATCHY FOG ACROSS MOST AREAS THIS EVENING/OVERNIGHT.  
 
AFTER BRIEF WARM ADVECTION SHOT LATE TONIGHT INTO EARLY WEDNESDAY, A  
STRONG COLD FRONT WILL MAKE ITS WAY ACROSS THE AREA ON WEDNESDAY AS  
BROAD UPPER PV ANOMALY SHIFTS ACROSS HUDSON BAY/ONTARIO. STRONGEST  
UPPER FORCING SHOULD MIGRATE NORTH/NORTHEAST OF LOCAL AREA, BUT  
GLANCING BLOW OF FORCING WITH THIS UPPER TROUGH AND MODEST LOW LEVEL  
FGEN FORCING SHOULD SUPPORT A BAND OF SNOW FILLING IN ALONG LOW  
LEVEL FRONT. MOISTURE AND DURATION OF DEEP MOISTURE WILL BE A  
LIMITING FACTOR WITH JUST A NARROW AXIS OF 3 G/KG 850 MB MIXING  
RATIOS IN VICINITY OF THE FRONT. A BAND OF LIGHT SNOW WITH A  
POTENTIAL OF ONE INCH ACCUMULATIONS IS EXPECTED ACROSS SW LOWER  
MI/NW IN, WITH EXPECTATION THAT FRONTAL FORCING WILL BECOME A LITTLE  
MORE WASHED OUT WITH SOUTHEAST EXTENT AS THE UPPER PV ANOMALY SHIFTS  
ACROSS SOUTHEAST CANADA. SOME LAKE RESPONSE POSSIBLE LATE WEDNESDAY  
NIGHT INTO EARLY THURSDAY BUT DEPTH OF LAKE INDUCED INSTABILITY  
APPEARS LIMITED ONCE AGAIN.  
 
AN EXPANSIVE LOW LEVEL ANTICYCLONE SHIFTS ACROSS THE REGION WED  
NIGHT INTO THU NIGHT WITH COLDEST MINS OF THE SEASON EXPECTED  
THURSDAY NIGHT. TEMPS SHOULD RAPIDLY DROP OFF EARLY THURSDAY EVENING  
BEFORE LIKELY BECOMING MORE STEADY LATE IN THE NIGHT. LOWS AROUND  
ZERO LOOK LIKE A GOOD CHANCE FOR MANY AREAS, AND POTENTIALLY SUB-  
ZERO FOR AREAS WITH FRESH SNOWPACK FROM THE WEDNESDAY SYSTEM. SUBTLE  
INCREASE IN SOUTHERLY WINDS TOWARD DAYBREAK FRIDAY SHOULD ALLOW FOR  
SOME 5 TO 10 DEGREE BELOW WIND CHILLS. SOME MODERATION TEMPERATURES  
IS EXPECTED FOR THE WEEKEND BUT REMAINING BELOW NORMAL FOR EARLY  
DECEMBER. THE LARGE SCALE SYNOPTIC PATTERN OF WEST COAST RIDGING AND  
SE CANADIAN TROUGHING COULD PROVIDE FAVORABLE LOW LEVEL  
BAROCLINICITY FOR POTENTIAL ADDITIONAL SYSTEMS TO TRACK ACROSS THE  
MID MS VALLEY/GREAT LAKES NEXT WEEKEND AND HAVE MAINTAINED  
BROADBRUSH CHANCE SNOW POPS NEXT WEEKEND INTO EARLY NEXT WEEK.  
 

 
   
AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/
 
 
ISSUED AT 1223 PM EST TUE DEC 2 2025  
 
PATCHY FOG MAY CONTINUE TO IMPACT AREAS NEAR KSBN OVER THE NEXT FEW  
HOURS, BUT LOW CEILINGS ARE EXPECTED TO PERSIST WITH MVFR/IFR  
CONDITIONS EXPECTED TO PREVAIL THROUGH MUCH OF THE TAF PERIOD. AT  
KSBN, CEILINGS INITIALLY NEAR 3K FEET AGL ARE EXPECTED TO LOWER TO  
NEAR 1K FEET AGL AFTER 21Z, PERSISTING THROUGH AROUND 06Z BEFORE  
SLOWLY LIFTING. MVFR CEILINGS AROUND 1500 FEET AGL WILL PREVAIL AT  
KFWA THROUGH TONIGHT. WINDS AT BOTH TERMINALS WILL REMAIN LIGHT.  
 

 
   
IWX WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
OH...NONE.  
MI...NONE.  
MARINE...SMALL CRAFT ADVISORY FROM 1 AM WEDNESDAY TO 7 PM EST THURSDAY  
FOR LMZ043-046.  
 

 
 

 
 
DISCUSSION...MARSILI  
AVIATION...HAMMER  
 
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