551  
FXUS63 KILX 052300  
AFDILX  
 
AREA FORECAST DISCUSSION...UPDATED AVIATION  
NATIONAL WEATHER SERVICE LINCOLN IL  
500 PM CST FRI DEC 5 2025  
   
KEY MESSAGES
 
 
- EXPECTED SNOWFALL AMOUNTS THIS WEEKEND HAVE TRENDED DOWNWARD  
SOME, ESPECIALLY TOWARD THE I-72 CORRIDOR. THE HIGHEST CHANCES  
OF MORE THAN 2 INCHES ARE NORTH OF PEORIA AND GALESBURG (ABOUT A  
60% CHANCE).  
 
- SOME POTENTIAL EXISTS FOR LIGHT FREEZING DRIZZLE AS THE SNOW  
ENDS EARLY SUNDAY.  
 
- TEMPERATURES WARM ENOUGH FOR RAIN TO OCCUR WITH THE NEXT SYSTEM  
TOWARD MID WEEK.  
 

 
   
SHORT TERM
 
(THROUGH SUNDAY)  
ISSUED AT 200 PM CST FRI DEC 5 2025  
 
MAIN CONCERN DURING THIS TIME FRAME WILL BE WITH THE UPCOMING  
CLIPPER SYSTEM. MORNING MODELS HAVE TRENDED NORTHWARD IN THE TRACK  
OF THE SNOW ACCUMULATIONS, WITH THE CAM GUIDANCE BRINGING THE  
SURFACE LOW TO NEAR THE IA/IL/MO TRIPLE POINT BY EARLY SUNDAY. AS  
SUCH, HEAVIER SNOW AMOUNTS ARE FOCUSING FROM CENTRAL IOWA INTO  
NORTHERN ILLINOIS. TAIL END OF THE HREF HIGHLIGHTS ABOUT A 40-50%  
CHANCE OF MORE THAN 2 INCHES FROM ABOUT MONMOUTH-PONTIAC NORTH,  
WITH THE NBM ABOUT 10% HIGHER. THE I-72 CORRIDOR IS DOWN TO ABOUT  
A 30-40% CHANCE OF AN INCH. WITH THE NORTHERN TRACK, THERE IS A  
LITTLE MORE CONCERN FOR MIXED OR FREEZING PRECIP ACROSS THE HEART  
OF THE FORECAST AREA. LATEST NAM SOUNDINGS SHOW A NOTICEABLE  
INVERSION AROUND 3000 FEET AS THE COLUMN MOISTENS FROM THE TOP  
DOWN, AND A LOSS OF ICE CRYSTALS AS WE GET INTO EARLY SUNDAY  
MORNING. THIS WOULD POINT TO SOME DRIZZLE OR FREEZING DRIZZLE  
POTENTIAL, AS TEMPERATURES ARE EXPECTED TO RISE TO FREEZING ACROSS  
THE SOUTH HALF OF THE FORECAST AREA. HOWEVER, THERE IS NO  
SIGNIFICANT "WARM NOSE" OF ABOVE-FREEZING TEMPERATURES OFF THE  
SURFACE, GENERALLY ONLY GETTING UP TO AROUND +1C IN THE INVERSION.  
WILL NEED TO WATCH THIS POTENTIAL AS WE GET CLOSER, AS ROAD  
TEMPERATURES ARE LIKELY TO REMAIN BELOW FREEZING. FOR NOW, WILL  
ONLY MENTION SNOW OR A RAIN/SNOW MIX IN THE FORECAST. MUCH OF THE  
PRECIP SHOULD BE OUT OF THE AREA BY LATE SUNDAY MORNING. NO WINTER  
WEATHER HEADLINES ARE PLANNED AT THIS TIME.  
 
TEMPERATURES REMAIN BELOW NORMAL THROUGH THE WEEKEND, BUT THEY  
SHOULD AT LEAST BE MORE REASONABLE. CAN'T RULE OUT SOME 40 DEGREE  
READINGS SOUTH OF I-70 WHERE SNOW COVER IS MORE LIKELY TO MELT  
OFF THIS WEEKEND.  
 
GEELHART  
   
LONG TERM
 
(MONDAY THROUGH NEXT FRIDAY)  
ISSUED AT 200 PM CST FRI DEC 5 2025  
 
NO SIGNIFICANT CHANGES IN THE FORECAST THINKING FOR THE UPCOMING  
WORK WEEK. WHILE WE REMAIN A GENERAL NORTHWEST UPPER FLOW, A GOOD  
PORTION OF THAT WILL BE COMING FROM MORE OF A PACIFIC FLOW,  
RESULTING IN SOME MILDER (RELATIVELY SPEAKING) TEMPERATURES FOR A  
TIME. HOWEVER, RIDGING BECOMES MORE PROMINENT ALONG THE WEST COAST  
BY LATE WEEK, WITH ANOTHER SURGE OF COLDER TEMPERATURES INTO THE  
MIDWEST.  
 
CLIPPER SYSTEMS WILL ZIP SOUTHEAST EVERY COUPLE OF DAYS, WITH THE  
TUESDAY NIGHT SYSTEM THE STRONGEST. THIS ONE IS ALSO THE FARTHEST  
NORTH, AND IS LIKELY TO BE MORE OF A RAIN MAKER THIS FAR SOUTH.  
WHILE THE LONGER RANGE MODELS BRING THE NEXT ONE INTO THE CENTRAL  
U.S. THURSDAY NIGHT OR EARLY FRIDAY, THE GFS APPEARS TO BE TOO FAR  
NORTH AT THIS TIME. EUROPEAN ENSEMBLES ARE FURTHER SOUTH, BUT ARE  
FAIRLY EVENLY SPLIT IN THE TIMING AND/OR SNOW POTENTIAL. NBM  
PRECIPITATION CHANCES NEAR 20% WILL BE SUFFICIENT AT THIS POINT.  
 
GEELHART  
 

 
   
AVIATION
 
(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)  
ISSUED AT 500 PM CST FRI DEC 5 2025  
 
A COLD FRONT WAS PUSHING INTO CENTRAL IA AT 23Z, AND WILL CROSS  
THE CENTRAL IL TERMINALS FROM THE NORTHWEST TONIGHT. AHEAD OF THE  
FRONT SOUTH TO SOUTHWEST WINDS AROUND 10 KT AND VFR SKIES WILL  
PREVAIL. MVFR CEILINGS WILL OVERSPREAD THE REGION BEHIND THE  
FRONT, WITH HIGHEST PROBABILITIES OF IFR CONDITIONS OCCURRING AT  
KBMI-KDEC-KCMI. THESE CLOUDS LOOK TO LINGER OVER THE AREA THROUGH  
MUCH OF SATURDAY.  
 
25  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
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