741
FXUS63 KLOT 132312
AFDLOT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL
512 PM CST THU NOV 13 2025
KEY MESSAGES
- UNSEASONABLY WARM WEATHER EXPECTED FRIDAY AND SATURDAY.
- SLIGHT CHANCE (20%) FOR LIGHT RAIN/SPRINKLES NEAR SOUTHERN
LAKE MICHIGAN SATURDAY.
- PRECIPITATION CHANCES RETURN MONDAY NIGHT INTO TUESDAY OF NEXT
WEEK.
DISCUSSION
ISSUED AT 252 PM CST THU NOV 13 2025
AN UPPER-LEVEL RIDGE AXIS WILL SHIFT EASTWARD INTO THE WESTERN
GREAT LAKES LATE FRIDAY INTO EARLY SATURDAY. THIS IN COMBINATION
WITH THE RETURN TO SOUTHERLY LOW-LEVEL FLOW ALONG THE WESTERN
PERIPHERY OF A SURFACE HIGH PRESSURE WILL PROMOTE A PERIOD OF
UNSEASONABLY WARM WEATHER ACROSS OUR AREA FOR FRIDAY AND ON
SATURDAY. HIGH TEMPERATURES ON FRIDAY SHOULD LARGELY END UP IN
THE 60S, AS A NORTHWARD SURGE IN LOW-LEVEL MOISTURE THROUGH THE
DAY DRIVES SURFACE DEWPOINTS THROUGH THE 40S INTO THE LOW 50S BY
SUNSET. DEWPOINTS WILL REMAIN IN THE LOW 50S FRIDAY NIGHT, ACTING
AS A FLOOR FOR OVERNIGHT LOW TEMPERATURES. ACCORDINGLY, EXPECT A
RATHER WARM NIGHT FOR MID NOVEMBER.
THE UNSEASONABLE WARMTH CONTINUES IN ADVANCE OF AN APPROACHING
COLD FRONT ON SATURDAY. HOWEVER, LOW-LEVEL CLOUD COVER MAY START
THE DAY, ALONG WITH THE NON-ZERO POTENTIAL FOR A FEW LIGHT
SHOWERS OR EVEN DRIZZLE. OTHERWISE, BREEZY SOUTHWEST WINDS WILL
TURN NORTHWESTERLY IN THE AFTERNOON FOLLOWING THE COLD FRONTAL
PASSAGE. THE COLDER AIRMASS WILL LAG THE COLD FRONTAL PASSAGE, SO
AFTERNOON TEMPERATURES ARE EXPECTED TO TOP OUT WELL INTO THE 60S
TO AROUND 70.
DRY AND COOLER, MORE SEASONABLE TEMPERATURES ARE SLATTED TO RETURN
FOR SUNDAY IN THE WAKE OF SATURDAY'S FRONTAL PASSAGE. THESE COOLER
TEMPERATURES ARE EXPECTED TO PERSIST INTO NEXT WEEK, THOUGH WE
WILL ALSO HAVE A COUPLE OF INCREASED CHANCES FOR PRECIPITATION
NEXT WEEK. THE FIRST WILL COME MONDAY INTO TUESDAY AS A
DISTURBANCE EJECTS OUT ACROSS THE MID-MISSISSPPI VALLEY. CURRENTLY
IT APPEARS THE P-TYPES MAY FAVOR MAINLY RAIN WITH THIS
DISTURBANCE. HOWEVER, THE COLUMN LOOKS TO BE PRECARIOUSLY CLOSE TO
SUPPORTING SOME WET SNOW ACROSS NORTHERN IL, SO THIS SOMETHING WE
WILL HAVE TO KEEP AN EYE ON. GIVEN THE UNCERTAINTY THIS FAR OUT,
I OPTED TO NOT ALTER THE NBM CHANCES FOR JUST RA.
OUR NEXT THREAT OF PRECIPITATION LOOKS TO COME LATER IN THE WEEK
IN RESPONSE TO A LARGER TROUGH AND ASSOCIATED STORM SYSTEM
SHIFTING OUT ACROSS THE PLAINS AND INTO THE MID-MISSISSIPI VALLEY
REGION. NOT SURPRISING, THERE IS STILL A LARGE DEAL OF ENSEMBLE
SPREAD WITH THIS SYSTEM, WHICH DOES LIMIT CONFIDENCE IN A MORE
PRECISE TIMING OF PRECIPITATION. NEVERTHELESS, THERE IS A NOTABLE
SIGNAL IN THE GUIDANCE SUPPORTING A PERIOD OF WETTER WEATHER
IN OUR GENERAL REGION LATER NEXT WEEK.
KJB
AVIATION /00Z TAFS THROUGH 06Z SATURDAY/
ISSUED AT 512 PM CST THU NOV 13 2025
SURFACE HIGH PRESSURE RIDGE AXIS HAS DRIFTED JUST EAST OF THE
TERMINALS EARLY THIS EVENING, ALLOWING WINDS TO BACK LIGHT SOUTH
OR SOUTH-SOUTHEAST. OTHER THAN A FEW HOUR PERIOD OF BROKEN MID-
LEVEL CLOUD BASES AROUND 10 KFT SCATTERING OUT EARLY THIS
EVENING, THESE TRENDS SHOULD PERSIST THROUGH THE NIGHT.
WINDS WILL BECOME LIGHT SOUTHWEST NEAR 10 KTS FRIDAY MORNING,
EVENTUALLY BACKING MORE SOUTH AGAIN BY FRIDAY EVENING. A COUPLE
OF THINGS OF NOTE FOR FRIDAY NIGHT ARE THE POTENTIAL FOR SOME
MARGINAL LLWS CONDITIONS AS A 35-40 KT SOUTHWESTERLY LOW LEVEL
JET DEVELOPS ABOVE 1500 FEET, AND THE POSSIBILITY FOR SOME LOW-
END VFR OR MVFR STRATUS TO DEVELOP. SINCE THE LLWS APPEARS TO
BE MARGINAL, DID NOT INCLUDE IN ORD/MDW 30-HOUR FORECASTS. DID
HOWEVER ADD A FEW030 MENTION TO INDICATE THE POTENTIAL TREND OF
SOME PATCHY STRATUS DEVELOPMENT LATER IN THE NIGHT.
RATZER
LOT WATCHES/WARNINGS/ADVISORIES
IL...NONE.
IN...NONE.
LM...NONE.
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