260
FXUS63 KILX 031632
AFDILX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LINCOLN IL
1032 AM CST WED DEC 3 2025
KEY MESSAGES
- WIDESPREAD FLURRIES AND PATCHY FREEZING DRIZZLE BEGINS EARLY
THIS AFTERNOON. ONLY LIMITED TRAVEL IMPACTS ARE ANTICIPATED, BUT
THERE COULD BE A FEW SLICK SPOTS WHEREVER WINTRY PRECIP BECOMES
FOCUSED. DRIVE WITH CAUTION, ESPECIALLY DURING THE AFTERNOON AND
EVENING COMMUTE.
- THE COLDEST AIR OF THE SEASON SO FAR WILL ARRIVE TONIGHT AND
LAST THROUGH FRIDAY MORNING. TAKE IMMEDIATE STEPS TO PROTECT
PEOPLE, PETS, AND PIPES FROM THE COLD.
UPDATE
ISSUED AT 1032 AM CST WED DEC 3 2025
SKIES ARE CLOUDIER THAN EXPECTED AND LOTS OF VERY LOW CLOUDS ARE
ADVECTING INTO THE CWA FROM THE SOUTH. THE THICKER CLOUD COVER
WILL HOLD TEMPS BACK THIS AFTERNOON, SO WILL BE LOWERING DAYTIME
HIGHS A COUPLE OF DEGREES OVER MOST OF THE AREA. COLD FRONT IS
STILL EXPECTED TO MOVE THROUGH THE AREA FROM THE NORTHWEST. A
NARROW RIBBON OF LIFT IS STILL BEING FORECASTED ALONG THE FRONT,
SO PRECIP IS POSSIBLE ALONG THE FRONT TODAY THROUGH TONIGHT. RADAR
RETURNS SHOW PRECIP SHOULD BE OCCURRING ACROSS PARTS OF IL.
HOWEVER, MOST OF THE RETURNS OVER THE CWA ARE NOT REACHING THE
GROUND AT THIS TIME. AS MOISTURE INCREASES BELOW THE CLOUD LAYER,
PRECIP WILL BEGIN TO OCCUR AT THE SURFACE. BASED ON FORECAST
SOUNDINGS, MOST OF THE PRECIP WILL BE SNOW. HOWEVER, FORECAST
SOUNDINGS SHOW US LOOSING CLOUD ICE BEHIND THE FRONT. SO, BELIEVE
SOME FZDZ IS POSSIBLE ALONG AND BEHIND THE FRONT IN AREAS WHERE
VERY LOW CLOUDS AND LOWER VISIBILITIES ARE PRESENT. ALREADY HAVE
SOME ISOLATED SPOTS OF FZDZ AND FZRA (15-25%) IN THE GRIDS AND SEE
NO REASON TO CHANGE THAT AT THIS TIME.
REMAINDER OF FORECAST FOR THIS AFTERNOON INTO THIS EVENING LOOKS
FINE. UPDATED GRIDS/FORECAST HAVE ALREADY BEEN SENT.
AUTEN
DISCUSSION
ISSUED AT 239 AM CST WED DEC 3 2025
A GOOD SURGE OF WARM AIR ADVECTION IS CURRENTLY UNDERWAY EARLY
THIS MORNING. THIS IS DUE TO SURFACE WINDS SHIFTING SOUTHERLY AS
SURFACE HIGH PRESSURE DEPARTS. AS A RESULT, TEMPERATURES ARE
EXPECTED TO SLOWLY CLIMB INTO THE LOWER 30S THIS AFTERNOON, AHEAD
OF AN APPROACHING COLD FRONT.
A DECENT SIGNAL PERSISTS FOR WINTRY PRECIPITATION TO DEVELOP
BEHIND THE FRONT BY EARLY AFTERNOON. THIS IS LINKED TO A
SHARPENING 700 MB FRONTOGENETIC (FGEN) BAND BENEATH A PAIR OF
PHASING JET STREAKS ALOFT. THE LATEST HREF GUIDANCE PLACES THE
GREATEST CHANCE (30-50%) FOR POPS ALONG THE I-70 CORRIDOR AROUND
00Z, WHERE WET-BULB TEMPERATURES ARE COLD ENOUGH TO SUPPORT SNOW.
THE MAIN CHALLENGE IS A PARTICULARLY NON-UNIFORM VERTICAL
MOISTURE PROFILE, WITH CLOUD ICE PRESENT IN SOME AREAS BUT ABSENT
IN OTHERS. THIS CREATES A PRECIPITATION TYPE (P-TYPE) CHALLENGE,
MAKING BOTH SNOW SHOWERS AND FREEZING DRIZZLE PLAUSIBLE. HREF QPF
LPMM STILL SUGGESTS A RANGE OF A TRACE TO 0.10 INCHES, WITH THE
HIGHER END MOST LIKELY WHERE THE FGEN BAND DEVELOPS, AND THE LOWER
END ELSEWHERE.
IN TOTAL, THIS POINTS TO WIDESPREAD FLURRIES AND PATCHY FREEZING
DRIZZLE, WITH THE POTENTIAL FOR A NARROW STRIPE OF LIGHT
ACCUMULATING SNOW. OUR BASE CASE FORECAST CALLS FOR A SKIFT OF
WINTRY PRECIPITATION IN MOST AREAS, BUT UP TO ONE INCH OF NEW SNOW
ACCUMULATION IS POSSIBLE (10% CHANCE) ALONG OR NEAR THE I-70
CORRIDOR THIS EVENING.
THE REGION THEN BRACES FOR THE COLDEST AIR OF THE SEASON SO FAR,
ARRIVING BEHIND THE ARCTIC FRONT AND LASTING FROM TONIGHT THROUGH
FRIDAY MORNING. THIS EXCEPTIONALLY COLD SPELL FOR EARLY DECEMBER
WILL BRING TEMPERATURES ABOUT 25-30 DEGREES BELOW AVERAGE.
OVERNIGHT LOWS WILL PLUMMET TO THE SINGLE DIGITS, AND DAYTIME
HIGHS WILL STRUGGLE TO REACH THE 20 DEGF, ESPECIALLY NORTH OF
I-70. ADDITIONALLY, WIND CHILL VALUES IN OUR NORTHERN AREAS ARE
EXPECTED TO APPROACH ADVISORY CRITERIA BOTH TONIGHT AND WEDNESDAY
NIGHT.
MARGINALLY WARMER AND CONTINUED DRY WEATHER IS EXPECTED BY THE
END OF THE WEEK, AS THE STORM SYSTEM PREVIOUSLY OF CONCERN FOR
FRIDAY REMAINS FORECAST TO PASS TO THE SOUTH. HOWEVER, A SIGNAL
FOR LIGHT ACCUMULATING SNOW RETURNS THIS WEEKEND. THIS IS
ATTRIBUTED TO A CLIPPER-LIKE SYSTEM MOVING ACROSS THE CORN BELT,
DRIVEN BY A CHOPPY NORTHWEST FLOW. THE LATEST GUIDANCE FROM THE
NBM AND GRAND ENSEMBLE (GEFS, GEPS AND EPS) CURRENTLY GIVES A LOW
(LESS THAN 20%) CHANCE FOR AT LEAST ONE INCH OF SNOW, THOUGH THIS
PROBABILITY MAY BE UNDERSTATED DUE TO EXISTING DIFFERENCES IN
TIMING AMONG THE MODELS.
THE EXTENDED FORECAST HINTS AT A SUBSTANTIAL WARM-UP BY THE
MIDDLE OF NEXT WEEK. THIS IS DUE TO A LONGWAVE RIDGE SETTLING OVER
THE WESTERN US, WHICH WILL BRING WARM, DOWNSLOPE FLOW ACROSS THE
PLAINS, EVENTUALLY ADVECTING INTO THE MIDWEST. DURING THIS PERIOD,
A SERIES OF CLIPPER SYSTEMS ARE EXPECTED TO TRACK ACROSS THE
UPPER MISSISSIPPI VALLEY INTO THE GREAT LAKES, POTENTIALLY GRAZING
OUR NORTHERN FORECAST AREAS AT TIMES.
MJA
AVIATION
(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 519 AM CST WED DEC 3 2025
VFR CONDITIONS HAVE RETURNED TO MOST REGIONAL TERMINALS THIS
MORNING, WITH THE EXCEPTION OF KCMI, WHERE IFR STRATUS PERSISTS,
MAINLY ALONG AND EAST OF I-57. THIS STRATUS IS FORECAST TO
GRADUALLY ERODE LATER THIS MORNING.
A COLD FRONT WILL MOVE INTO THE AREA THIS AFTERNOON. EXPECT SSW
WINDS OF 10-15 KT TO SLOWLY SHIFT TO WESTERLY, AND THEN
NORTHWESTERLY, AHEAD OF AND BEHIND THE FRONT. AS THE FRONT SETTLES
IN, MVFR/IFR CEILINGS ARE EXPECTED TO REDEVELOP. THERE IS A 30%
CHANCE OF LIGHT PRECIPITATION, WITH THE TYPE REMAINING UNCERTAIN
(LIGHT SNOW OR DRIZZLE) DUE TO SURFACE TEMPERATURES HOVERING NEAR
FREEZING THROUGHOUT THE AFTERNOON AND EARLY EVENING.
VFR CONDITIONS ARE FORECAST TO RETURN LATE TONIGHT AT ALL SITES
AS CLOUDS LIFT AND BREAK BEHIND THE DEPARTING FRONT.
MJA
ILX WATCHES/WARNINGS/ADVISORIES
NONE.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page