180  
FXUS63 KILX 201112  
AFDILX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LINCOLN IL  
612 AM CDT TUE OCT 20 2026  
   
KEY MESSAGES
 
 
- DRY AND MILD WEATHER IS EXPECTED THROUGH THIS WEEKEND ALONG  
WITH A FAIR AMOUNT OF SUNSHINE AND FAIRLY LIGHT WINDS. HIGHS  
WILL CLIMB INTO THE 70S WITH LOWS IN THE 40S AND LOWER 50S  
TODAY THROUGH SUNDAY.  
 

 
   
DISCUSSION
 
 
ISSUED AT 315 AM CDT TUE OCT 20 2026  
 
DELIGHTFUL FALL WEATHER WILL LIKELY CONTINUE THROUGH AT LEAST  
EARLY NEXT WEEK ACROSS CENTRAL AND SOUTHEAST IL. THE 08Z/3 AM  
SURFACE MAP SHOWS LARGE 1031 MB HIGH PRESSURE OVER EASTERN  
ONTARIO PROVINCE AND RIDGING SSW ACROSS THE GREAT LAKES REGION  
AND IL/IN. ALOFT A MID/UPPER LEVEL RIDGE WAS OVER THE MS RIVER  
VALLEY WITH CUTOFF UPPER LEVEL LOWS/TROF OFF THE MID ATLANTIC  
COAST AND WEST COAST/CA. NIGHTTIME MICROPHYSICS SATELLITE  
IMAGERY SHOWS A SWIRL OF SCATTERED TO BROKEN MID/HIGH CLOUDS  
OVER CENTRAL AND SOUTHERN IL, AND MORE WIDESPREAD HIGH CLOUDS  
IN SOUTHERN/SW IL. TEMPERATURES NOT AS COOL AS PAST FEW NIGHTS,  
WITH CURRENT MERCURY LEVELS IN THE 40S, RANGING FROM 38F AT NWS  
LINCOLN TO 51F AT THE BLOOMINGTON AIRPORT AND 50F AT PEORIA  
AIRPORT. LIGHT TO CALM WINDS WITH DEWPOINTS IN THE LOW TO MID  
40S, WITH A FEW SPOTS HAVING UPPER 30S AT LINCOLN AND LACON.  
 
SURFACE HIGH PRESSURE STRENGTHENS TO ~1033 MB AS IT DRIFTS  
EASTWARD INTO QUEBEC BY SUNSET WHILE STILL RIDGING BACK OVER IL  
AND UPPER LEVEL RIDGE STAYING OVER IL. STRONG SUBSIDENCE OVER IL  
TODAY, WITH HIGH CLOUDS DECREASING DURING THIS MORNING, LASTING  
LONGEST IN SOUTHEAST IL WHERE PARTLY TO MOSTLY CLOUDY SKIES  
EARLY THIS MORNING GIVES WAY TO SUNNY SKIES BY LATE MORNING.  
WITH DEWPOINTS A BIT HIGHER AND WITH LIGHT TO CALM WINDS AND  
HIGH CLOUDS DECREASING, COULD SEE PATCHY SHALLOW GROUND FOG  
EARLY THIS MORNING NEAR RIVERS/CREEK BEDS AND OTHER WATER AREAS  
BUT COVERAGE LIMITED AND WHATEVER FOG DEVELOPS WILL LIFT QUICKLY  
AFTER SUNRISE. HIGHS TODAY IN THE LOWER 70S WITH VERY LIGHT  
WINDS WITH HIGH PRESSURE RIDGE OVERHEAD. FAIR TONIGHT WITH LOWS  
40-45F. LITTLE CHANGE WITH WEATHER ON WED AS SURFACE AND UPPER  
LEVEL RIDGE STAY OVER IL. SOME CLOUDS INCREASING OVER THE IL  
RIVER VALLEY/WESTERN CWA ON WED BUT STILL A FAIR AMOUNT OF  
SUNSHINE WED. TEMPS 1-2 DEGREES WARMER WITH HIGHS 70-75F AND  
VERY LIGHT TO CALM WINDS.  
 
ANOTHER HIGH PRESSURE DRIFTS EASTWARD ACROSS SOUTHERN ONTARIO  
WED NIGHT AND PUSHES A WEAKENING COLD FRONT SOUTHWARD INTO THE  
SOUTHERN GREAT LAKES BY EARLY THU MORNING AND WILL HAVE LITTLE  
AFFECT ON OUR WEATHER WITH NEARBY HIGH PRESSURE RIDGE AND LIGHT  
NE FLOW DEVELOPING OVER CWA ON THU. AMPLE SUNSHINE THU WITH  
HIGHS IN THE LOW TO MID 70S. THE LARGE HIGH PRESSURE SYSTEM  
STRENGTHENS TO 1036 MB OR STRONGER AS IT MOVES OVER PA/NY BY  
SATURDAY MORNING AND STAYS NEAR THE MID ATLANTIC STATES THROUGH  
THE WEEKEND AND SURFACE RIDGING SW INTO THE LOWER MS RIVER  
VALLEY PINCHING OFF GULF MOISTURE FROM RETURNING TO IL.  
CIRCULATION AROUND HIGH PRESSURE GIVES A LIGHT SE FLOW ON FRIDAY  
WITH SUNNY SKIES, AND HIGHS IN LOW TO MID 70S. STRONG MID/UPPER  
LEVEL RIDGE INTO THE EASTERN PLAINS ON FRIDAY SHIFTS EAST INTO  
IL ON SATURDAY ENSURE DRY AND MILD WEATHER. A BIT STRONGER SSE  
WINDS SATURDAY AND SOME INCREASING CLOUDS OVERNIGHT FRI NIGHT  
INTO SATURDAY AS SKIES BECOME PARTLY CLOUDY. SW WINDS ON SUNDAY  
WITH PARTLY SUNNY SKIES AND HIGHS IN THE MID TO UPPER 70S.  
 
GFS MODEL IS MOST AGGRESSIVE WITH PUSHING A COLD FRONT AND SOME  
RAIN CHANCES SE INTO CENTRAL IL LATE MONDAY AFTERNOON AND  
MONDAY NIGHT WHILE GEM AND ECMWF MODELS KEEP CWA DRY AS SYSTEM  
WEAKENS SINCE MOVING INTO STRONG MID/UPPER LEVEL RIDGE FROM THE  
OH/TN RIVER VALLEYS INTO THE SOUTHEAST STATES. HIGHS 70-75F OVER  
CENTRAL/SE IL MON AND UPPER 60S NW OF THE IL RIVER BUT IF FRONT  
IS SLOWER TO MOVE IN WOULD LIKELY BE WARMER THERE TOO. TEMPS  
COOL CLOSER TO SEASONABLE LEVELS NEXT TUE/WED.  
 
THE CLIMATE PREDICTION CENTER (CPC) 6-10 DAY OUTLOOK FOR OCT  
25-29TH HAS 50-60% CHANCE OF ABOVE NORMAL TEMPERATURES OVER IL  
AND 35-45% CHANCE OF BELOW NORMAL PRECIPITATION (ESPECIALLY  
SOUTHEAST IL). CPC 8-14 DAY OUTLOOK FOR OCT 27-NOV 2 HAS 55-60%  
CHANCE OF ABOVE NORMAL TEMPERATURES OVER CENTRAL/SE IL AND  
35-45% CHANCE OF ABOVE NORMAL PRECIPITATION (ESPECIALLY IN  
WESTERN IL). AS OF OCT 18TH, ILLINOIS HAS 63% OF CORN HARVESTED  
AND 66% OF SOYBEANS HARVESTED, RUNNING 5% AHEAD OF SCHEDULE.  
GENERALLY LOOKS LIKE FAVORABLE WEATHER CONDITIONS INTO NEXT WEEK  
FOR THE 2ND HALF OF HARVEST SEASON. GIVEN THE DRY AND MILD  
WEATHER PATTERN FOR AT LEAST NEXT WEEK, AND DEVELOPING MODERATE  
DROUGHT IN SOUTHEAST IL, SOME FIRE WEATHER CONCERN WITH POSSIBLE  
FIELD FIRES. THOUGH LIGHTER WINDS AND RH'S STAYING ABOVE  
CRITICAL THRESHOLDS SHOULD HELP LIMIT FIELD FIRES.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/
 
 
ISSUED AT 612 AM CDT TUE OCT 20 2026  
 
VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES NEXT 24HRS WITH  
FEW CIRRUS AND CLEAR SKIES. WINDS WILL REMAIN LIGHT AND  
VARIABLE UNDER HIGH PRESSURE.  
 

 
   
ILX WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  
 

 
 

 
 
KEY MESSAGES...07  
DISCUSSION...07  
AVIATION...AUTEN  
 
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