497
FXUS63 KLOT 152320
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
620 PM CDT MON SEP 15 2025
KEY MESSAGES
- WARM AND DRY CONDITIONS PERSIST THROUGH THE WORK WEEK.
- PERIODIC SHOWER AND THUNDERSTORM CHANCES RETURN FOR THE WEEKEND
(20-40%).
DISCUSSION
ISSUED AT 136 PM CDT MON SEP 15 2025
A BLOCKY UPPER-LEVEL FLOW PATTERN, CENTERED ACROSS THE GREAT
LAKES, WILL CONTINUE TO SUPPORT QUIESCENT WEATHER CONDITIONS
ACROSS OUR AREA THROUGH THE WEEK. ACCORDINGLY, DRY WEATHER WITH
MOSTLY CLEAR SKIES EACH DAY WILL FOSTER UNSEASONABLY WARM
TEMPERATURES, WITH INLAND HIGHS IN THE 80S TO NEAR 90 (WARMEST
TOWARD WESTERN AND CENTRAL ILLINOIS) THROUGH THE REMAINDER OF THE
WORK WEEK. CLOSER TO THE LAKE, RELATIVELY WEAK SURFACE FLOW AMIDST
EXPANSIVE SURFACE HIGH PRESSURE WILL FAVOR DAILY INLAND DRIFTING
LAKE BREEZES. THIS WILL THUS RESULT IN COOLER TEMPERATURES (MAINLY
IN THE 70S) NEAR THE LAKE MICHIGAN LAKESHORE.
WHILE QUIET AND DRY WEATHER WILL PERSIST IN THIS BLOCKED PATTERN
THROUGH THE REST OF THE WORK WEEK, THIS PATTERN WILL BEGIN TO
BREAK LATE IN THE WEEK AS A WESTERN TROUGH (AND/OR POTENTIAL CUT-
OFF LOW) BEGINS TO SLIDE EASTWARD TOWARDS THE GREAT LAKES. THE NET
RESULT OF THIS WILL BE INCREASING CHANCES FOR PERIODIC SHOWERS
AND THUNDERSTORMS FOR THIS WEEKEND INTO EARLY NEXT WEEK. THIS
WILL ALSO BE PAIRED WITH COOLER MORE SEASONABLE TEMPERATURES IN
THE 70S.
KJB
AVIATION /00Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 620 PM CDT MON SEP 15 2025
NO SIGNIFICANT WEATHER CONCERNS THROUGH THE CURRENT TAF PERIOD.
EAST TO NORTHEAST WINDS WILL GRADUALLY DIMINISH THIS EVENING
BECOMING LIGHT AND EVEN VARIABLE. STEADIER EAST TO EAST-
SOUTHEAST WINDS WILL RETURN TOWARD MIDDAY TUESDAY. VFR
CONDITIONS ARE EXPECTED FOR MOST OF THE AREA. LOCALIZED SHALLOW
FOG TOWARD DAYBREAK CANNOT BE COMPLETELY RULED OUT CLOSER TO THE
LAKE AND THE WISCONSIN STATELINE. WITH A DRIER AIR MASS NEAR
THE SURFACE, THERE IS HIGHER CONFIDENCE OF LIMITED TO NO
IMPACTS TO TERMINALS.
DK
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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