406  
FXUS63 KLOT 220548  
AFDLOT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
1248 AM CDT SUN MAR 22 2026  
   
KEY MESSAGES  
 
- MILD WEATHER CONTINUES THIS EVENING, BUT A COLD FRONTAL  
PASSAGE EARLY SUNDAY MORNING WILL RESULT IN BLUSTERY AND  
SHARPLY COLDER AND CLOUDY CONDITIONS FOR SUNDAY.  
 
- COOLER WEATHER PERSISTS ON MONDAY, BEFORE TEMPERATURES  
MODERATE INTO MIDWEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 200 PM CDT SAT MAR 21 2026  
 
MID AND HIGH LEVEL CLOUD COVER WILL CONTINUE TO CLEAR THE AREA  
THIS AFTERNOON, FOSTERING A MAINLY SUNNY AFTERNOON. TEMPERATURES  
THIS AFTERNOON WILL TOP OUT WELL INTO THE 70S, IF NOT THE LOW  
80S (IN SOME AREAS) AS BREEZY SOUTHWESTERLY LOW-LEVEL FLOW  
DEVELOPS IN RESPONSE TO THE COMPACT SURFACE LOW TRACKING INTO  
NORTHERN WI. CONDITIONS WILL ALSO WARM THROUGH THE AFTERNOON  
ALONG THE LAKE MICHIGAN SHORE AS THE FLOW SHIFTS SOUTHWESTERLY.  
 
THESE UNSEASONABLY MILD CONDITIONS WILL PERSIST TONIGHT, BUT  
WILL COME TO A QUICK END EARLY SUNDAY MORNING AS A STRONG COLD  
FRONT DROPS SOUTH ACROSS THE AREA. IN ADVANCE OF THIS FRONT,  
TEMPERATURES WILL HOVER IN THE UPPER 50S TO THE LOW 60S FOR MOST  
OF TONIGHT. HOWEVER, WITH THE FRONTAL PASSAGE AROUND, OR A BIT  
BEFORE DAYBREAK SUNDAY MORNING, A MUCH COLDER LOW-LEVEL AIRMASS  
WILL BE DRIVEN IN OFF OF LAKE MICHIGAN ON GUSTY (30-35 MPH)  
NORTH-NORTHEASTERLY WINDS. THE RESULT WILL BE QUICKLY FALLING  
TEMPERATURES INTO THE 40S SUNDAY MORNING (AFTERNOON) ALONG AND  
NORTH (SOUTH) OF THE ILLINOIS AND KANKAKEE RIVERS. ONCE  
TEMPERATURES DO DROP, DO NOT EXPECT MUCH IF ANY RECOVERY SUNDAY  
AFTERNOON. IN FACT, THE PRESENCE OF A CONTINUAL FEED OF COLDER  
AIR OFF OF LAKE MICHIGAN ALONG WITH AN EXTENSIVE POST FRONTAL  
LOW-LEVEL STATUS DECK WILL HOLD TEMPERATURES FAIRLY STEADY IN  
THE 40S SUNDAY AFTERNOON (LOW 40S NEAR THE LAKE). THE  
POSSIBILITY ALSO EXISTS FOR SOME SCATTERED POST FRONTAL SHOWERS  
DURING THE DAY.  
 
THE COOLER WEATHER WILL PERSIST ON MONDAY AS A SURFACE HIGH  
SHIFTS INTO THE WESTERN GREAT LAKES. ACCORDINGLY, HIGH  
TEMPERATURES ARE GENERALLY EXPECTED TO BE IN THE 40S (COOLEST  
NEAR THE LAKE). THE MAIN DIFFERENCES FROM SUNDAY'S WEATHER WILL  
BE THE LIGHTER NORTHEASTERLY WINDS AND LESS CLOUD COVER FOR THE  
DAY MONDAY.  
 
BROAD WNW MID AND UPPER-LEVEL FLOW WILL TAKE HOLD ACROSS THE  
REGION NEXT WEEK. THIS WILL RESULT IN A SERIES OF WEATHER  
DISTURBANCES AND ASSOCIATED SURFACE COLD FRONTS CROSSING THE  
GREAT LAKES REGION DURING THE MIDDLE AND LATER PART OF NEXT  
WEEK. IN ADVANCE OF THESE FRONTS, CONDITIONS WILL WARM BACK WELL  
INTO THE 50S ON SOUTHWESTERLY LOW-LEVEL WINDS ON TUESDAY.  
THEREAFTER, MILD WEATHER DOES LOOK TO PERSIST TO SOME DEGREE FOR  
WEDNESDAY AND THURSDAY. HOWEVER, A COUPLE OF COLD FRONTS MAY  
SHIFT INTO THE AREA. THE FIRST MAY SHIFT INTO NORTHERN PARTS OF  
THE AREA ON WEDNESDAY BEFORE STALLING JUST SOUTH OF THE LAKE. IF  
THIS OCCURS, ONSHORE FLOW NORTH OF THE BOUNDARY WOULD BE LIKELY  
TO PROMOTE COOLER CONDITIONS THAN CURRENTLY FORECAST FOR  
WEDNESDAY, PARTICULARLY ACROSS NORTHEASTERN IL. OTHERWISE,  
TEMPERATURES COULD EASILY MAKE A RUN BACK AROUND 60F FOR  
WEDNESDAY. THURSDAY COULD THEN END UP BEING THE WARMEST DAY NEXT  
WEEK AS A LOW-LEVEL THERMAL RIDGE ADVECTS OVER THE AREA IN  
ADVANCE OF THE NEXT APPROACHING COLD FRONT. THIS SECOND COLD  
FRONT LOOKS TO BE MORE SUBSTANTIAL THAN WEDNESDAY'S.  
ACCORDINGLY, TEMPERATURES ARE EXPECTED TO TREND BACK DOWN INTO  
THE 40S AND LOW 50S ON BREEZY NORTHEASTERLY WINDS AT THE END OF  
THE WEEK.  
 
GENERALLY DRY WEATHER IS EXPECTED THROUGH THE PERIOD, WITH ONLY  
SOME LOW (20-30%) CHANCES OF PRECIPITATION SUNDAY, AND AGAIN  
THURSDAY.  
 
KJB  
 
 
   
AVIATION /06Z TAFS THROUGH 12Z MONDAY/  
 
ISSUED AT 1248 AM CDT SUN MAR 22 2026  
 
- WIND SHIFT TO GUSTY NNE EXPECTED EARLY THIS MORNING WITH  
FAIRLY STRONG AND GUSTY WINDS EXPECTED TO PERSIST THROUGH THE  
DAY.  
- MVFR CIGS PROBABLE, MAINLY NEAR THE LAKE, LATE THIS MORNING  
THROUGH THE AFTERNOON.  
 
LAKE ENHANCED COLD FRONT WILL SWEEP ACROSS THE TERMINALS EARLY  
THIS MORNING RESULTING IN WIND SHIFT TO RATHER STRONG AND GUSTY  
NORTH-NORTHEAST. THE STRONG NNE WINDS WILL PERSIST THROUGH THE  
DAY TODAY AT ALL TERMINALS; PROBABLY REMAINING STRONG AND GUSTY  
INTO THIS EVENING FOR THE TERMINALS CLOSER TO THE LAKE  
(ORD/MDW/GYY). PEAK GUSTS OCCASIONALLY TO AROUND 30KT ARE  
EXPECTED LATE THIS MORNING THROUGH THE AFTERNOON AT ORD, MDW,  
AND GYY.  
 
FAIRLY DRY AIR MASS BEHIND THE FRONT HAS THUS FAR PREVENTED ANY  
STRATUS DEVELOPMENT, HOWEVER, MVFR STRATOCUMULUS FIELD IS  
EXPECTED TO DEVELOP LATER THIS MORNING INTO THE AFTERNOON.  
THIS WILL PROBABLY RESULT IN SOME MVFR CIGS, PARTICULARLY CLOSER  
TO LAKE MICHIGAN, THOUGH CONFIDENCE IN CIGS ISN'T TERRIBLY HIGH  
AT THIS TIME.  
 
- IZZI  
 
 
   
LOT WATCHES/WARNINGS/ADVISORIES  
 
IL...NONE.  
IN...NONE.  
LM...SMALL CRAFT ADVISORY FROM 7 AM THIS MORNING TO 1 PM CDT MONDAY  
FOR THE IL NEARSHORE WATERS.  
 
SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 PM CDT  
MONDAY FOR THE IN NEARSHORE WATERS.  
 
 
 
 
 
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