790
FXUS63 KLOT 111109
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
609 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 /12Z TAFS THROUGH 18Z MONDAY/
ISSUED AT 609 AM CDT SUN OCT 11 2026
FORECAST CONCERNS FOR THE TERMINALS...
- POTENTIAL FOR LOW-LEVEL WIND SHEAR TONIGHT, ESPECIALLY NEAR
RFD.
- BREEZY SOUTHWEST WINDS GUSTING 20-25 KTS ON MONDAY.
MID-LEVEL RIDGING (HIGH PRESSURE) WILL CONTINUE TO RESIDE ACROSS
THE REGION THROUGH THE TAF PERIOD WHICH WILL KEEP GENERALLY
QUIET WEATHER AROUND. SOUTHEAST WINDS THIS MORNING WILL
GRADUALLY BECOME MORE SOUTH-SOUTHWESTERLY BY MIDDAY WITH SPEEDS
REMAINING AROUND 5-7 KTS. THE EXCEPTION WILL BE AT GYY AND MDW
WHERE A WEAK LAKE BREEZE WILL KEEP WINDS MORE EASTERLY BEFORE
DIRECTIONS BECOME SOUTHWEST AFTER SUNSET THIS EVENING.
OTHERWISE, EXPECT THE CURRENT VFR CIRRUS TO EXIT THE AREA LATER
THIS MORNING LEAVING US WITH MOSTLY CLEAR SKIES THROUGH THE
PERIOD.
THERE IS A POTENTIAL FOR SOME LOW-LEVEL WIND SHEAR TO DEVELOP
AFTER MIDNIGHT TONIGHT AS A 30-35 KT LOW-LEVEL JET PIVOTS INTO
THE AREA. GIVEN THAT SURFACE WINDS WILL SLOWLY BE INCREASING
OVERNIGHT IT SEEMS THE LLWS THREAT IS VERY MARGINAL AND THUS
HAVE LEFT OUT OF THE TAFS FOR NOW. BUT WILL CONTINUE TO MONITOR
FORECAST TRENDS. REGARDLESS, BREEZY SOUTHWEST WINDS WILL DEVELOP
ON MONDAY WITH GUSTS PEAKING INTO THE 20-25 KT FOR MONDAY
AFTERNOON.
YACK
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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