426  
FXUS63 KLOT 110700  
AFDLOT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
200 AM CDT SUN OCT 11 2026  
   
KEY MESSAGES
 
 
- NEAR RECORD HIGH TEMPS POSSIBLE AND GUSTY SOUTHWEST WINDS  
MONDAY.  
 
- ACTIVE PATTERN NEXT WEEK WITH A SERIES OF PRECIPITATION  
CHANCES, AND THEN TURNING COLDER INTO NEXT WEEKEND.  
 

 
   
DISCUSSION
 
 
ISSUED AT 200 AM CDT SUN OCT 11 2026  
 
A WEAK RIDGE OF HIGH PRESSURE WILL SLOWLY DRIFT EAST OF THE AREA  
THIS AFTERNOON INTO THIS EVENING. THIS WILL ALLOW FOR LIGHT  
WINDS THIS MORNING TO SLOWLY BECOME SOUTH/SOUTHWEST THROUGH THE  
DAY. HIGH/MID CLOUDS EARLY WILL DEPART THIS MORNING LEAVING  
MOSTLY SUNNY SKIES WITH HIGHS RANGING FROM THE MID 70S EAST TO  
THE LOWER 80S WEST. ONSHORE WINDS WILL ALSO KEEP AREAS NEAR LAKE  
MICHIGAN COOLER, MAINLY IN THE LOWER 70S.  
 
AN UPPER RIDGE WILL BUILD ACROSS THE AREA TONIGHT INTO MONDAY  
ALLOWING FOR HIGH TEMPS TO REACH THE MID 80S AREAWIDE MONDAY  
WITH SOME AREAS LIKELY REACHING THE UPPER 80S. SOUTHWEST WINDS  
MAY ALSO GUST INTO THE 20-30 MPH RANGE MONDAY AFTERNOON. STILL  
SOME UNCERTAINTY ON THE EXTENT OF CLOUD COVER WHICH MAY BE A  
LIMITING FACTOR FOR TEMPS/WINDS BASED ON HOW MUCH MIXING OCCURS.  
STRONG LOW LEVEL WINDS MONDAY NIGHT SHOULD KEEP LOW TEMPS  
RATHER MILD, PERHAPS IN THE UPPER 50S/LOWER 60S FOR MUCH OF THE  
AREA. CONSENSUS AMONG THE MODELS NOW SUGGESTS WINDS WILL TURN  
WESTERLY TUESDAY MORNING AS A TROUGH OF LOW PRESSURE PASSES  
ACROSS THE AREA, BUT THE EXPECTED MAIN COLD FRONT WITH  
NORTHERLY WINDS MAY BE DELAYED UNTIL TUESDAY AFTERNOON/EVENING.  
THIS WOULD ALLOW FOR ANOTHER POTENTIALLY VERY WARM DAY TUESDAY  
WITH THE BLENDED TEMPS RANGING FROM THE UPPER 70S NORTH TO THE  
MID 80S SOUTH OF I-80 AND THESE ARE CERTAINLY POSSIBLE, SO MADE  
NO CHANGES FROM THIS DISTANCE.  
 
AS FOR PRECIP CHANCES, THERE IS A SMALL CHANCE FOR SOME WARM AIR  
ADVECTION SHOWERS MONDAY MORNING THAT APPEAR THEY WILL REMAIN  
NORTH OF THE AREA. THEN AS THE ABOVE MENTIONED TROUGH MOVES  
ACROSS THE AREA TUESDAY MORNING, THERE COULD BE SOME SHOWERS AND  
POSSIBLY A FEW THUNDERSTORMS, BUT COVERAGE LOOKS RATHER LOW AND  
EXPECTING MUCH OF THE AREA TO REMAIN DRY.  
 
A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS, FOR AT LEAST PART  
OF THE AREA WILL ARRIVE TUESDAY NIGHT INTO WEDNESDAY MORNING AS  
THE COLD FRONT IS PUSHING SOUTH INTO CENTRAL IL AND CENTRAL IN.  
CURRENT TRENDS SUGGEST THE BEST CHANCES FOR RAIN WILL BE SOUTH  
OF I-80, THOUGH STILL UNCERTAINTY FOR THE NORTHERN EXTENT WITH  
THIS PRECIP POTENTIAL. HIGH PRESSURE WILL QUICKLY MOVE ACROSS  
THE NORTHERN GREAT LAKES WEDNESDAY NIGHT, WHICH SHOULD PUSH THE  
FRONT AND PRECIP CHANCES FAR ENOUGH SOUTH FOR A BREAK IN THE  
PRECIP UNTIL THE FRONT LIFTS BACK NORTH THURSDAY AHEAD OF A  
STRONGER COLD FRONT THAT ARRIVES THURSDAY NIGHT OR FRIDAY  
MORNING. DESPITE VERY GOOD ENSEMBLE SUPPORT FOR AT LEAST A FEW  
DAYS OF MUCH COLDER TEMPERATURES ACROSS THE REGION, THE ECMWF IS  
WARMER AND ADDS UNCERTAINTY TO THE OVERALL TEMP EXPECTATIONS.  
BLENDED GUIDANCE NOW HAS LOW TEMPS IN THE MID/UPPER 30S FOR NEXT  
SUNDAY MORNING AND THESE SEEM REASONABLE GIVEN THE ENSEMBLES.  
THOUGH IF THE COLD AIR DOES MATERIALIZE ACROSS THE REGION, TEMPS  
COULD BE EVEN COLDER. CMS  
 

 
   
AVIATION /06Z TAFS THROUGH 12Z MONDAY/
 
 
ISSUED AT 1221 AM CDT SUN OCT 11 2026  
 
NO MAJOR FORECAST CONCERNS ARE EXPECTED FOR THIS TAF PERIOD AS  
MID-LEVEL RIDGING (HIGH PRESSURE) WILL KEEP TRANQUIL WEATHER IN  
PLAY. WINDS WILL BE LIGHT WITH SPEEDS AROUND 5-7 KTS THROUGH THE  
PERIOD WITH SOUTHEASTERLY DIRECTIONS TONIGHT BECOMING MORE  
SOUTH-SOUTHWEST BY MIDDAY ON SUNDAY. HOWEVER, A WEAK LAKE BREEZE  
IS FORECAST TO DEVELOP AND OOZE INLAND AT GYY AND MOST LIKELY  
MDW WHICH WILL KEEP WINDS MORE EASTERLY AT THESE SITES THROUGH  
SUNDAY EVENING BEFORE WINDS TURN SOUTHWESTERLY SUNDAY NIGHT.  
WHILE THE LAKE BREEZE COULD GET AS FAR WEST AS ORD, CONFIDENCE  
IS LOW ON IT REACHING THERE AT THIS TIME SO HAVE LEFT IT OUT OF  
THE CURRENT FORECAST. OTHERWISE, EXPECT THE LINGERING VFR CIRRUS  
FROM THE REMNANTS OF ISAIAS TO EXIT THE AREA BY DAYBREAK  
RESULTING IN MOSTLY CLEAR SKIES FOR THE FORECAST PERIOD.  
 
YACK  
 

 
   
LOT WATCHES/WARNINGS/ADVISORIES
 
 
IL...NONE.  
IN...NONE.  
LM...NONE.  
 

 
 

 
 
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