849
FXUS63 KLOT 091128
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
528 AM CST MON FEB 9 2026
KEY MESSAGES
- MILDER TEMPERATURES ARE EXPECTED FOR MUCH OF THE UPCOMING
WORK WEEK.
DISCUSSION
ISSUED AT 126 AM CST MON FEB 9 2026
A PERSISTENT STRATUS LAYER WITH BASES AROUND 5-7 KFT SHOULD
GRADUALLY SHIFT NORTHEAST AND SLOWLY ERODE THROUGH THIS MORNING
AS THE CLOUD-BEARING FLOW TURNS SOUTHWESTERLY WITH TIME.
SATELLITE IMAGERY INDICATES WE'LL CONTINUE TO PICK UP ADDITIONAL
HIGH-LEVEL CLOUD COVER THIS MORNING AND AFTERNOON, BUT PRECIP-
FREE CONDITIONS ARE EXPECTED. WARM ADVECTION WILL INTENSIFY A
BIT THIS AFTERNOON WHICH SHOULD ALLOW TEMPERATURES TO PUSH INTO
THE 40S ACROSS THE SOUTHWEST QUADRANT OF THE CWA, EVEN AMIDST
TEMPERED INSOLATION WITH THE INCOMING CIRRUS CLOUD COVER.
THIS EVENING/OVERNIGHT, A MODEST 1005 MB SURFACE LOW IS FORECAST
TO SLIDE ACROSS SOUTHERN WISCONSIN. AHEAD OF THE LOW, AN
IMPRESSIVE LLJ IS FORECAST TO RAMP UP THROUGH THE NIGHT, WITH
GUIDANCE RESOLVING 55-60 KT FLOW AROUND 900 MB. NEAR-SURFACE
STABILITY WILL LIMIT MUCH OF THIS MOMENTUM FROM TRANSFERRING TO
THE GROUND, BUT SOME INTERMITTENT GUSTS AROUND 20-25 KTS WILL BE
POSSIBLE AT TIMES. EVENTUALLY, A COLD FRONT WILL SWEEP ACROSS
THE AREA THROUGH EARLY TUESDAY MORNING. ASIDE FROM THE TYPICALLY
TOO-MOIST NAM/NAMNEST, NOT SEEING A STRONG SIGNAL FOR DRIZZLE AS
THE LOW PIVOTS INTO LOWER MICHIGAN AND HAVE RESULTANTLY
MAINTAINED A DRY FORECAST.
IN THE WAKE OF THE MORNING FRONTAL PASSAGE, FAIRLY STOUT
PRESSURE RISES (5-6 MB/3 HRS) COMBINED WITH STEEPENING LOW-LEVEL
LAPSE RATES SHOULD FACILITATE THE DEVELOPMENT OF GUSTY WNW/NW
WINDS THROUGH TUESDAY MORNING INTO THE AFTERNOON. NBM WINDS LOOK
UNDERDONE IN THE POST-FRONTAL AIRMASS ON TUESDAY, AND SUSPECT
SOME BOOSTING WILL BE NECESSARY WITH GUIDANCE SUPPORTING A
PERIOD OF 30 MPH GUSTS POST FROPA. EVEN WITH LOW-LEVEL CAA
CONTINUING INTO THE AFTERNOON, HIGH TEMPERATURES LOOK LIKE
THEY'LL MANAGE TO TO PUSH INTO THE LOW 40S ACROSS MOST OF THE
REGION, AND EVEN INTO THE MID/UPPER 40S SOUTH OF I-80.
THE NEXT DISTURBANCE IS SLATED TO MARCH ACROSS THE REGION ON
THURSDAY. EPHEMERAL/DISORGANIZED MID-LEVEL FRONTOGENESIS IS
FORECAST TO DEVELOP THROUGH THURSDAY MORNING AS 700-600 MB
CONFLUENCE INCREASES AS AN ASSOCIATED SHORTWAVE SHIFTS OUT OF
THE DAKOTAS. FORECAST SOUNDINGS REVEAL A DECENT AMOUNT OF
ANTECEDENT DRY AIR BELOW 700 MB AS EAST TO SOUTHEAST LOW-LEVEL
FLOW DEVELOPS, SO THERE'S SOME UNCERTAINTY REGARDING WHETHER
PRECIPITATION (SNOW) WILL BE ABLE TO BREAK THROUGH. NBM POPS ON
THURSDAY-THURSDAY NIGHT HAVE BEEN PRETTY STEADY IN THE 20-30
PERCENT RANGE AND THIS STILL LOOKS REPRESENTATIVE AT THIS POINT
WITH RELATIVELY BETTER CHANCES FOR SNOW TO OUR WEST.
ON FRIDAY, A SOUTHERN STREAM WAVE APPEARS LIKELY TO MOVE ACROSS
BAJA CALIFORNIA INTO SONORA, MEXICO AND EVENTUALLY THROUGH THE
ARKLATEX ON SATURDAY. WHETHER OR NOT THIS WAVE LOOSELY PHASES
WITH A SERIES OF NORTHERN STREAM DISTURBANCES REMAINS A BIT
UNCLEAR, BUT THESE FEATURES COLLECTIVELY MAY BRING SOME
POTENTIAL FOR PRECIP BACK INTO PARTS OF THE REGION LATE IN THE
WEEKEND.
CARLAW
AVIATION /12Z TAFS THROUGH 18Z TUESDAY/
ISSUED AT 528 AM CST MON FEB 9 2026
FORECAST CONCERNS FOR THE TERMINALS...
- PERIOD OF LOW-LEVEL WIND SHEAR TONIGHT
- GUSTY NORTHWEST WINDS BEHIND A COLD FRONT TUESDAY MORNING
MID-LEVEL RIDGING (HIGHER PRESSURE) WILL SWING THROUGH THE
TERMINALS TODAY RESULTING IN QUIET WEATHER AND GENERALLY LIGHT
WINDS. WIND DIRECTIONS WILL START THE DAY OUT OF THE SOUTHEAST
BUT WILL GRADUALLY BECOME MORE SOUTHERLY THIS AFTERNOON BEFORE
TURNING SOUTHWESTERLY THIS EVENING. WINDS SPEEDS THROUGH THE
AFTERNOON SHOULD GENERALLY BE IN THE 5-10 KT RANGE WITH SPEEDS
INCREASING SLIGHTLY TO AROUND 10-13 KTS OVERNIGHT AS A SURFACE
LOW DEVELOPS AND MOVES ACROSS THE UPPER MIDWEST.
AHEAD OF THIS SURFACE LOW WILL BE A RATHER STOUT LOW-LEVEL JET
(50-60 KTS) WHICH WILL PIVOT OVER NORTHERN IL AND NORTHWEST IN
TONIGHT RESULTING IN A PERIOD OF LLWS FROM 03-04Z TO 11-12Z,
EARLIEST AT RFD AND LATER AT THE CHICAGO TERMINALS. WHILE MOST
GUIDANCE KEEPS THE STRONGEST WINDS JUST ABOVE 2000 FT AGL,
45-50 KT WESTERLY WINDS WILL BE RESIDING AROUND 1500 FT DURING
THIS TIME. GIVEN THE STRENGTH OF THE LOW-LEVEL JET SOME
OCCASIONAL 20-25 KT GUSTS MAY BE SEEN AT TIMES OVERNIGHT, BUT
DUE TO THE EXPECTED LOW FREQUENCY HAVE LEFT OUT OF THE TAFS.
HEADING INTO TUESDAY, A COLD FRONT WILL PIVOT THROUGH THE
TERMINALS AND TURN WINDS NORTHWESTERLY IN ITS WAKE. BEHIND THE
FRONT WINDS WILL ALSO QUICKLY INCREASE WITH 25-30 KT GUSTS
EXPECTED THROUGH AT LEAST TUESDAY MORNING. THAT SAID, DEPENDING
ON HOW QUICKLY THE ATMOSPHERE MIXES BEHIND THE FRONT LOCALLY
HIGHER GUSTS IN EXCESS OF 30 KTS ARE POSSIBLE.
OTHERWISE, EXPECT GRADUALLY INCREASING VFR CLOUDS THROUGH THE
TAF PERIOD. HOWEVER, THERE IS A SMALL CHANCE (<15%) FOR SOME
2500-3000 FT CLOUDS TO DEVELOP EARLY TUESDAY MORNING WITH THE
COLD FRONT. SINCE THE COVERAGE THESE CLOUDS IS MORE UNCERTAIN
HAVE OPTED TO JUST TEASE WITH A SCT030 MENTION FOR NOW.
YACK
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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