614  
FXUS63 KLOT 160009  
AFDLOT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
609 PM CST THU JAN 15 2026  
   
KEY MESSAGES  
 
- ACCUMULATING SNOW IS EXPECTED TONIGHT, LIKELY RESULTING IN  
HAZARDOUS TRAVEL CONDITIONS.  
 
- ISOLATED TO SCATTERED GUSTY SNOW SHOWERS LATE FRIDAY AFTERNOON  
INTO EARLY EVENING MAY PRODUCE LOCALLY SLIPPERY TRAVEL FOR  
THE EVENING COMMUTE.  
 
- SEVERAL CLIPPER-LIKE SYSTEMS WITHIN NORTHWEST FLOW ALOFT WILL  
BRING PERIODS OF SNOW SHOWERS AND RENEWED BOUTS OF VERY COLD  
AND WINDY CONDITIONS. BITTERLY COLD CONDITIONS ARE EXPECTED  
SUNDAY NIGHT THROUGH EARLY TUESDAY.  
 
 
   
DISCUSSION  
 
ISSUED AT 250 PM CST THU JAN 15 2026  
 
THROUGH EARLY FRIDAY AFTERNOON:  
 
AFTERNOON WATER VAPOR IMAGERY DEPICTS A SHORTWAVE IMPULSE  
WORKING ACROSS MINNESOTA EN ROUTE TO WISCONSIN. REGIONAL RADAR  
IMAGERY SHOWS A FEW POCKETS OF SNOW SHOWERS ON THE LEADING EDGE  
OF THIS WAVE WORKING INTO NORTHWESTERN PORTIONS OF WI. AHEAD OF  
THE SNOW SHOWERS IS A PLUME OF SNOW ALOFT THAT DOESN'T APPEAR TO  
BE MAKING IT TO THE GROUND OWING TO DRY LOW LEVEL AIR PRECEDING  
THE WAVE. THE SYSTEM WILL WORK ACROSS NORTH-CENTRAL WI TONIGHT  
AND DRAG ITS COLD FRONT ACROSS THE CWA PROVIDING OUR NEXT  
OPPORTUNITY FOR ACCUMULATING SNOW. ISENTROPIC ASCENT WILL KICK  
OFF LATE THIS AFTERNOON IN THE LOW LEVEL WARM ADVECTION WING IN  
ADVANCE OF THIS WAVE. HOWEVER, WITH THE LOW LEVELS BEING SO DRY,  
THERE WON'T BE MUCH MOISTURE TO LOFT INITIALLY AND WE TOO MAY  
END UP WITH A FEW HOUR PERIOD OF VIRGA SNOW SHOWERS OR POSSIBLY  
A FEW FLURRIES. THE SNOW SHOWER POTENTIAL WILL REALLY PICK UP  
DURING THE MID-LATE EVENING PERIOD WHILE THE LOW LEVELS QUICKLY  
MOISTEN UP. FROM THERE, WE EXPECT A FEW HOUR PERIOD OVER ANY  
GIVEN LOCATION OF LIGHT ACCUMULATING SNOW INTO THE OVERNIGHT.  
THIS SHOULD LEAD TO REDUCTIONS IN VISIBILITY, POSSIBLY DOWN TO  
OR EVEN BELOW ONE MILE FROM TIME TO TIME, AND SLIPPERY ROAD  
CONDITIONS.  
 
MODEL GUIDANCE LIKES THE IDEA OF A FEW HOUR LULL IN ACTIVITY  
AHEAD OF THE STORM'S COLD FRONT IN WHICH WE MAY END UP DRY OR  
WITH ONLY LINGERING FLURRIES LATE OVERNIGHT INTO VERY EARLY  
FRIDAY. THE FRONT WILL APPROACH OUR WESTERN CWA DURING THE  
PREDAWN HOURS AND A SECOND PUSH OF ACCUMULATING LIGHT SNOW IS  
ANTICIPATED ALONG AND IMMEDIATELY AHEAD OF THE BOUNDARY. THE  
TIME WINDOW FOR THIS SECOND PUSH WOULD BE PREDAWN IN OUR WEST  
THROUGH ABOUT MID-MORNING TO EXIT TO OUR EAST. THIS WILL  
REINFORCE THE VISIBILITY AND SLIPPERY TRAVEL CONCERNS FOR THE  
MORNING COMMUTE. WHILE THIS DOESN'T APPEAR TO BE AN OVERLY  
IMPACTFUL EVENT, AT THE LEAST EXPECT A SLOWER-MOVING COMMUTE  
TOMORROW. BY THE END OF TOMORROW MORNING, WIDESPREAD  
ACCUMULATIONS AROUND OR JUST OVER AN INCH ARE FORECAST WITH 2"  
BEING ON THE HIGHER END OF EXPECTATIONS. AFTER THE TROUGH AXIS  
SHOVES THE MAIN BODY OF PRECIP TO OUR EAST, THE LATE MORNING  
THROUGH EARLY AFTERNOON PERIOD COULD FEATURE SCATTERED FLURRIES  
AROUND THE AREA.  
 
THERE IS A WEAK SIGNAL AMONG SOME CAMPS FOR US TO LOSE OUT ON  
CLOUD ICE DURING A FEW HOUR WINDOW OVERNIGHT AND AGAIN DURING  
THE MORNING. FORECAST SOUNDINGS FROM THE GFS AND NAM ARE MOST  
BULLISH ON THIS POTENTIAL, BUT EVEN THEN THE SIGNAL IS VERY  
MARGINAL AND NEITHER MODEL RESOLVES ANY FREEZING PRECIP  
OUTRIGHT. LATEST RAP AND HRRR SOUNDINGS DEPICT A DEEPER  
SATURATED LAYER THROUGH THE NIGHT WHICH WOULD FAVOR ALL SNOW. IF  
ANYTHING, THE SIGNAL IS SLIGHTLY STRONGER TOMORROW DURING THE  
LATE MORNING AND EARLY AFTERNOON, BUT THIS WOULD COME AFTER THE  
SYSTEM PRECIP AND IN THE FORM OF ONLY A BRIEF PERIOD OF LIGHT  
FREEZING DRIZZLE, IF AT ALL. PLUS, TEMPERATURES SHOULD BE  
PUSHING ABOVE FREEZING RIGHT AROUND THIS TIME WHICH SHOULD  
FURTHER LIMIT ANY POTENTIAL IMPACTS. EXPECTATIONS FOR NOW ARE  
FOR PRECIP TO REMAIN IN THE FORM OF SNOW WITH NO FORMAL MENTION  
OF FREEZING RAIN/DRIZZLE IN THE FORECAST, BUT WILL KEEP A CLOSE  
EYE ON OBSERVATIONS AS THE SYSTEM MOVES ACROSS.  
 
THE COLD AIR WILL REALLY BEGIN TO FILL IN ALOFT DURING THE  
AFTERNOON. THIS WILL STEEPEN UP LOW LEVEL LAPSE RATES AS A  
SECONDARY TROUGH AXIS AND VORT LOBE ARE PROGGED TO SWING ACROSS  
THE CWA. THIS WILL PROVIDE YET ANOTHER CHANCE FOR ACCUMULATING  
SNOW, POSSIBLY HEAVIER AT TIMES. MORE DETAILS ON THIS  
AFTERNOON/EVENING POTENTIAL CAN BE FOUND IN THE LONG TERM  
DISCUSSION BELOW.  
 
IN OTHER NEWS, THE WARM ADVECTION LATER TODAY WILL KEEP  
TEMPERATURES RATHER STEADY IN THE LOWER AND MIDDLE 20S FROM NOW  
THROUGH MOST OF THE OVERNIGHT. THE STRONGER WARM ADVECTION JUST  
IN ADVANCE OF THE COLD FRONT WILL DRIVE TEMPERATURES UP A FEW  
DEGREES PRIOR TO DAYBREAK AND WE SHOULD WAKE UP TO MIDDLE AND  
UPPER 20S. WE'RE LOOKING AT MIDDLE AND UPPER 30S FOR THE  
AFTERNOON. GUSTS WILL ALSO BEGIN TO PICK UP OVERNIGHT WITH THE  
INITIAL PUSH OF SNOW AND STAY UP THROUGH THE DAY ON FRIDAY.  
SOUTHWEST TO WEST WINDS WILL GUST TO BETWEEN 25 AND 30 MPH, WITH  
THE STRONGEST WINDS EXPECTED OVERNIGHT AND FRIDAY AFTERNOON.  
 
DOOM  
 
LATE FRIDAY AFTERNOON THROUGH THURSDAY:  
 
STOUT RIDGING CURRENTLY DEVELOPING OVER THE EASTERN PACIFIC  
TOWARD THE GULF OF ALASKA WILL DISLODGE A SERIES OF ARCTIC  
DISTURBANCES SSE TOWARD THE GREAT LAKES REGION THIS WEEKEND  
THROUGH EARLY NEXT WEEK. BITTERLY COLD CONDITIONS ARE EXPECTED,  
ESPECIALLY SUNDAY NIGHT INTO TUESDAY. EACH SHOT OF COLDER AIR AS  
WELL AS PERSISTENT CYCLONIC FLOW ALOFT WILL SUPPORT PERIODIC  
SNOW SHOWERS AND FLURRIES DURING THIS TIME.  
 
THE FIRST ARCTIC FRONT WILL SWEEP ACROSS THE AREA LATE FRIDAY  
AFTERNOON INTO MID-EVENING. LOW-LEVEL MOISTURE PROFILES APPEAR  
MARGINAL FOR SNOW SHOWERS WITH THE FRONT, BUT A MODESTLY DEEP  
LAYER (UP TO 10KFT) OF STEEP LOW-LEVEL LAPSE RATES COMBINED WITH  
TEMPS QUICKLY FALLING THROUGH THE 20S AND WNW WINDS GUSTING TO  
30 MPH OR HIGHER DOES RAISE CONCERN FOR LOCALIZED SNOW SQUALL  
CONDITIONS ROUGHLY IN THE 4-8PM WINDOW. GIVEN THAT THIS ALIGNS  
WITH THE PEAK FRIDAY EVENING COMMUTE TIME, IT WOULD NOT TAKE  
LONG FOR IMPACTS TO QUICKLY MOUNT. STILL FEEL MOISTURE  
AVAILABILITY WILL BE THE LIMITING FACTOR FOR GENUINE ROBUST  
SQUALLS, THOUGH UPSTREAM TRENDS ACROSS IOWA EARLIER IN THE  
AFTERNOON SHOULD PROVIDE SOME LEAD TIME IF COVERAGE AND/OR  
INTENSITY IS HIGHER THAN CURRENTLY EXPECTED.  
 
ANOTHER PAIR OF TROUGH AXES WILL BRING A RENEWED CHANCE OF SNOW  
SHOWERS SATURDAY EVENING AND AGAIN SUNDAY AFTERNOON INTO THE  
EVENING. INVERSION HEIGHTS LOWERING TO UNDER 6KFT WILL LIMIT  
INTENSITY, BUT WITH THE CLOUD LAYER RESIDING MOSTLY IN THE DGZ  
FOR BOTH PERIODS, EVEN MEAGER MOISTURE WILL RESULT IN AT LEAST  
SOME LIGHTER SNOW SHOWERS.  
 
EXPECT DAYTIME HIGHS THIS WEEKEND TO SETTLE IN THE MID TO UPPER  
TEENS AMID GUSTY WNW TO WSW WINDS, RESULTING IN WIND CHILLS  
TOPPING OUT ONLY JUST ABOVE ZERO. A NEXT PUSH OF ARCTIC AIR WILL  
ARRIVE LATE SUNDAY AFTERNOON AND EVENING, WITH NOTABLY COLDER  
CONDITIONS SUNDAY NIGHT INTO TUESDAY. MINIMUM WIND CHILLS MONDAY  
MORNING ARE EXPECTED TO BE AROUND -20 DEGREES, WITH THE  
POTENTIAL THAT A COLD WEATHER ADVISORY (-25 DEGREES) IS NEEDED  
FOR AT LEAST SOME OF THE AREA. WITH THE COLD START TO THE DAY,  
HIGHS MONDAY MAY STRUGGLE TO REACH 10 DEGREES, WITH MAXIMUM WIND  
CHILLS REMAINING SOLIDLY BELOW ZERO. WINDS WILL BEGIN TO  
DIMINISH MONDAY NIGHT AS A SURFACE HIGH PASSES SOUTH OF THE  
AREA, BUT WIND CHILLS AS LOW AS -15 DEGREES CAN BE EXPECTED  
TUESDAY MORNING.  
 
BEYOND TUESDAY, STRONG BAROCLINICITY DEVELOPING ACROSS THE  
CENTRAL CONUS WILL SUPPORT A MORE ACTIVE PERIOD OF WEATHER NEAR  
OR SOUTH OF THE AREA. STILL A LOT OF DISCREPANCIES IN THE  
BROADER MODEL/ENSEMBLE SYSTEMS CHIEFLY DUE TO UNCERTAINTY AS TO  
WHERE THE BAROCLINIC ZONE RESIDES WITH RESPECT TO OUT AREA.  
 
KLUBER  
 
 
   
AVIATION /00Z TAFS THROUGH 06Z SATURDAY/  
 
ISSUED AT 609 PM CST THU JAN 15 2026  
 
KEY MESSAGES:  
 
- TWO PERIODS OF STEADY SNOWFALL ARE EXPECTED TONIGHT, EACH  
LIKELY WITH IFR VISIBILITIES.  
 
- GUSTY SNOW SHOWERS WILL LIKELY AFFECT THE TERMINALS TOMORROW  
AFTERNOON/EVENING.  
 
- MVFR CEILINGS ARE EXPECTED TO BE PREVALENT THROUGH MUCH OF  
THE TAF PERIOD.  
 
MULTIPLE ROUNDS OF SNOW ARE EXPECTED DURING THE 00Z TAF PERIOD  
AS A SPRAWLING WEATHER SYSTEM TRAVERSES THE GREAT LAKES. AN  
INITIAL THUMP OF SNOW IS EXPECTED TO ARRIVE DURING THE LATTER  
HALF OF THIS EVENING. WHILE THE STEADIER SNOWFALL ISN'T EXPECTED  
TO LAST FOR MORE THAN 3 HOURS, IT WILL LIKELY FALL AT A STEADY  
ENOUGH CLIP TO REDUCE VISIBILITIES TO IFR LEVELS FOR A TIME AND  
PRODUCE A QUICK COATING OF SNOW ACCUMULATION. THEREAFTER, A 3-4  
HOUR LULL IN THE STEADIER SNOWFALL IS EXPECTED, THOUGH IT  
REMAINS POSSIBLE THAT SOME FLURRIES OR POOR QUALITY SNOW SHOWERS  
OCCUR DURING THIS RELATIVE LULL.  
 
A SECOND WAVE OF STEADY SNOWFALL WILL LIKELY ARRIVE AT THE  
TERMINALS CLOSER TO DAYBREAK. MUCH LIKE THE FIRST ROUND OF SNOW,  
THIS FOLLOW-UP ROUND OF SNOW WILL ALSO LIKELY LAST NO MORE THAN  
3-4 HOURS AT ANY ONE LOCATION WHILE ALSO PRODUCING IFR  
VISIBILITIES AND ANOTHER QUICK COATING OF ACCUMULATION. THE  
TOTAL SNOWFALL ACCUMULATION BETWEEN THE TWO ROUNDS OF STEADIER  
SNOWFALL WILL LIKELY END UP BEING SOMEWHERE AROUND ONE INCH.  
 
ANOTHER LULL IN THE SNOWFALL IS EXPECTED FROM MID-MORNING  
THROUGH THE EARLY AFTERNOON TOMORROW. HOWEVER, SCATTERED GUSTY  
SNOW SHOWERS ARE LIKELY TO DEVELOP DURING THE AFTERNOON AND  
PRODUCE ON-AND-OFF VISIBILITY REDUCTIONS THROUGH AT LEAST THE  
EARLY EVENING TOMORROW. AIR TEMPERATURES WARMING INTO THE MID  
30S BY THIS POINT SHOULD TEND TO LIMIT ANY DUSTINGS TO COLDER  
AND GRASSY SURFACES, IF THAT.  
 
CEILINGS ARE GENERALLY FAVORED TO STAY IN THE MVFR FLIGHT  
CATEGORY FROM DURING AND AFTER THE FIRST ROUND OF SNOW THROUGH  
MUCH OF THE REST OF THE TAF PERIOD, THOUGH THERE IS SOME CHANCE  
FOR IFR CEILINGS TO BE OBSERVED BOTH DURING AND JUST AFTER THE  
STEADIEST SNOWFALL. WINDS WILL REMAIN OUT OF A SOUTHWESTERLY  
DIRECTION THROUGH TOMORROW MORNING, GUSTING IN EXCESS OF 20 KTS  
ON AT LEAST AN OCCASIONAL BASIS. THEY WILL THEN SHIFT WESTERLY  
BEHIND A COLD FRONT TOMORROW AFTERNOON, THOUGH SIMILAR (OR  
SLIGHTLY HIGHER) WIND MAGNITUDES ARE EXPECTED TO BE RETAINED  
BEHIND THE FRONT.  
 
OGOREK  
 
 
   
HYDROLOGY  
 
ISSUED AT 1209 PM CST THU JAN 15 2026  
 
THE UPCOMING EXTENDED PERIOD OF VERY COLD TEMPERATURES WILL LIKELY  
RESULT IN THE RAPID DEVELOPMENT OF ICE ON AREA RIVERS AND STREAMS  
WHICH MAY INCREASE THE CHANCE OF LOCALIZED ICE JAM FLOODING. LAST  
WEEK'S HEAVY RAINFALL HAS RESULTED IN INCREASED STREAMFLOW IN  
SEVERAL BASINS, INCLUDING THE FOX, DES PLAINS, AND ILLINOIS RIVER  
BASINS. THIS HIGHER STREAMFLOW WILL RESULT IN A GREATER POTENTIAL  
FOR FREEZE UP ICE JAM FLOODING.  
 
- IZZI  
 
 
   
LOT WATCHES/WARNINGS/ADVISORIES  
 
IL...NONE.  
IN...NONE.  
LM...SMALL CRAFT ADVISORY UNTIL 6 PM CST FRIDAY FOR WINTHROP HARBOR  
IL TO GARY IN.  
 
SMALL CRAFT ADVISORY UNTIL 6 PM CST FRIDAY FOR GARY TO BURNS  
HARBOR IN-BURNS HARBOR TO MICHIGAN CITY IN.  
 
 
 
 
 
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