734  
FXUS63 KLOT 110138  
AFDLOT  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE, IL  
738 PM CST WED DEC 10 2025  
   
KEY MESSAGES
 
 
- ADDITIONAL CLIPPER SYSTEMS WILL MOVE ACROSS THE BROAD REGION  
TOMORROW AND SATURDAY. AT THIS POINT, SHOVEABLE-SNOW APPEARS  
MOST FAVORED ALONG AND SOUTH OF INTERSTATE 80 WITH BOTH.  
 
- BITTERLY COLD TEMPERATURES AND POTENTIALLY DANGEROUSLY COLD  
WIND CHILLS ARE EXPECTED THIS WEEKEND.  
 
- THERE IS A GROWING SIGNAL FOR A PATTERN CHANGE TOWARD MILDER  
(AND LESS SNOWY) CONDITIONS NEXT WEEK.  
 

 
   
UPDATE
 
 
ISSUED AT 738 PM CST WED DEC 10 2025  
 
RECENT RADAR IMAGERY ACROSS THE REGION DEPICTS A COMPACT REGION  
OF FLURRIES AND SNOW SHOWERS EXTENDING FROM NEAR DAVENPORT,  
IOWA TO BLOOMINGTON, ILLINOIS. THE AREA OF SNOW APPEARS TO BE  
TIED TO A WEAKENING MID-LEVEL WAVE, WHICH IS POISED TO MORE OR  
LESS SHEAR OUT WHILE PASSING INTO CENTRAL ILLINOIS OVER THE NEXT  
3 TO 6 HOURS. WITH SURFACE OBSERVATIONS INDICATING LARGELY 10  
MILE VISIBILITY BENEATH ALL RADAR RETURNS, EARLIER CONCERNS  
ABOUT A QUICK HIT OF SNOW AND SLIPPERY TRAVEL CONDITIONS ARE  
THANKFULLY GOING AWAY. NEVERTHELESS, WILL MAINTAIN SOMEWHAT HIGH  
POPS (>60%) FOR SNOW SHOWERS, FOCUSED SOUTHWEST OF A LINE FROM  
MENDOTA TO CISSNA PARK, IL.  
 
OUTSIDE THE COMPACT REGION OF SNOW SHOWERS, NIGHTTIME  
MICROPHYSICS SATELLITE IMAGERY CAPTURES EXPANSIVE STRATUS ACROSS  
THE REGION QUITE WELL AT THIS HOUR, WHICH HAS THUS FAR LIMITED  
THE ABILITY FOR TEMPERATURES TO FALL MUCH FROM WHERE THE WERE  
BEFORE SUNSET. MODEL GUIDANCE IS PRETTY AWFUL AT HANDLING COOL  
SEASON STRATUS, SO DO SHARE THE SAME DOSE OF SKEPTICISM AS THE  
DAY SHIFT THAT CLOUDS WILL CLEAR ALLOWING FOR TEMPERATURES TO  
TANK OVERNIGHT AS DEPICTED IN MOST MODEL GUIDANCE. WITH THAT  
SAID, HAVE BEEN WATCHING THE VERY SLOW PROGRESS OF THE CLEARING  
LINE ACROSS NORTHEASTERN WISCONSIN, WHICH DOES APPEAR POISED TO  
EVENTUALLY WORK SOUTHWARD ERODING STRATUS ACROSS FAR NORTHERN OR  
NORTHEASTERN IL BY DAYBREAK THURSDAY. AT THIS POINT, FEEL  
PRETTY COMFORTABLE MAINTAINING THE INHERITED OVERNIGHT  
TEMPERATURE FORECAST SHOWING TEENS NORTH OF I-88 AND LOW TO MID  
20S SOUTH OF I-80, KEEPING IN MIND EITHER LOCATION COULD END UP  
LOWER (NORTH) OR HIGHER (SOUTH) DEPENDING ON EVENTUAL CLOUD  
TRENDS.  
 
WITH REGARD TO THE CLIPPER SYSTEM TOMORROW... AM NOTING A  
SURPRISING SPREAD IN THE STRUCTURE OF THE SYSTEM ADVERTISED BY  
THE LATEST MODEL GUIDANCE GIVEN THE SHORT LEAD TIME. IT SEEMS  
LIKE THE STRUCTURAL DIFFERENCES ARE AT LEAST PARTIALLY TIED TO  
THE SPEED AT WHICH THE UPPER-LEVEL LOW CURRENTLY OVER THE  
NORTHERN GREAT LAKES SHIFTS NORTHEASTWARD TOWARD NOVA SCOTIA  
TONIGHT INTO TOMORROW. A SLOWER EVOLUTION OF THE DEPARTING  
UPPER-LEVEL LOW KEEPS THE CLIPPER SYSTEM SOMEWHAT SUPPRESSED AND  
TO THE SOUTHWEST, WITH THE SURFACE LOW PASSING MORE OR LESS  
FROM KANSAS CITY, MISSOURI TO PADUCAH, KENTUCKY. THE BAND OF  
SNOW WITH THE CLIPPER WOULD BE TIED TO A PLUME OF STEEP MID-  
LEVEL LAPSE RATES JUST NORTH OF THE SURFACE LOW EXTENDING FROM  
CENTRAL IOWA TOWARD EASTERN KENTUCKY, WITH A SHARP EDGE MORE OR  
LESS SLICING THROUGH NORTHERN ILLINOIS (TERMINATING SOMEWHERE  
ALONG A LINE FROM MENDOTA, ILLINOIS TO FOWLER, INDIANA?). THIS  
SCENARIO IS ADVERTISED BY THE GEFS/EPS/NAM SUITE AND IS  
CURRENTLY REFLECTED IN OUR GRIDDED DATABASE.  
 
A SLIGHTLY FASTER EVOLUTION OF THE DEPARTING UPPER-LEVEL LOW,  
AS DEPICTED BY RAP/HRRR/RRFS GUIDANCE, OPENS THE DOOR FOR A  
STRONGER CLIPPER/SURFACE LOW TRACKING FROM OMAHA, NEBRASKA TO  
BLOOMINGTON, INDIANA. THE RAP/HRRR/RRFS SUITE HAS BEEN LOCKED  
ONTO SUCH AN EVOLUTION, INCLUDING NOTABLY STRONGER/BACKED  
850-700MB LOW-LEVEL FLOW DIRECTED RIGHT INTO NORTHERN ILLINOIS.  
SUCH STRONGER/BACKED 850-700MB FLOW WOULD TIGHTEN THE LOW-LEVEL  
BAROCLINIC ZONE AND ELUCIDATE A STRONGER FRONTOGENETICAL  
RESPONSE, ALTOGETHER SUPPORTING A MUCH BROADER SHIELD OF SNOW  
ENCOMPASSING MUCH OR OUR AREA WELL TO THE NORTH OF THE LAPSE-  
RATE DRIVEN SNOW ACROSS CENTRAL ILLINOIS. WHILE THE QPF WITH A  
STRONGER SYSTEM WOULD NOT BE OVERLY IMPRESSIVE (GENERALLY 0.15  
NEAR THE WISCONSIN STATE LINE TO 0.35" NEAR/SOUTH OF US-24),  
RESPECTABLE LIFT (AROUND 15 UBAR/SEC) FOCUSED RIGHT BELOW THE  
DGZ (THE SO-CALLED "CROSS-HAIRS" SIGNATURE) WOULD SUPPORT  
SLIGHTLY FLUFFIER SNOW RATIOS OF 15:1, ALTOGETHER LEADING TO A  
BROAD SWATH OF 2 TO LOCALLY 5 INCHES OF SNOW RIGHT ACROSS  
NORTHERN ILLINOIS AND NORTHWESTERN INDIANA. THIS SCENARIO WOULD  
OBVIOUSLY BE A BIT MORE PROBLEMATIC IN TERMS OF IMPACTS ACROSS  
OUR AREA. (THOUGH IT SHOULD BE NOTED THAT SHOVABLE-SNOW DOES  
FALL ACROSS OUR SOUTHERN FORECAST AREA IN EITHER SCENARIO).  
 
AT THIS POINT, IT'S HARD TO SAY EXACTLY WHICH OUTCOME IS MORE  
LIKELY. INCOMING 00Z HRRR GUIDANCE SEEMS PRETTY SIMILAR TO PRIOR  
RUNS, PROVIDING LITTLE INSIGHT INTO WHETHER ONE CAMP IS CAVING  
TOWARD TOWARD THE OTHER. AND, OF COURSE, SOMETHING IN BETWEEN IS  
VERY MUCH A REASONABLE OUTCOME AS WELL. GIVEN DIFFERENCES  
BETWEEN THE GEFS/EPS/NAM AND RAP/HRRR/RRFS SUITES START TO  
BECOME DISCERNIBLE BY ABOUT 06 TO 09Z TONIGHT, THE MIDNIGHT  
SHIFT SHOULD BE IN A BETTER POSITION TO EVALUATE THE FORTHCOMING  
EVOLUTION OF THE CLIPPER SYSTEM AND DETERMINE THE NEED FOR A  
WINTER WEATHER ADVISORY ACROSS PART (OR ALL?) OR OUR AREA. SO,  
WILL LEAVE THE GRIDDED DATABASE UNCHANGED FOR NOW.  
 
UPDATED TEXT PRODUCTS (REALLY COSMETIC UPDATES) WILL BE SENT  
SOON.  
 
BORCHARDT  
 

 
   
DISCUSSION
 
 
ISSUED AT 228 PM CST WED DEC 10 2025  
 
THROUGH THURSDAY NIGHT:  
 
ACTIVE WINTER WEATHER PATTERN WILL CONTINUE WITH A COUPLE MORE  
SHOTS OF SNOW JUST IN THE NEXT 24-36 HOURS.  
 
FIRST UP, SHEARED/CHANNELIZED SHORTWAVE IS NOTED ON WATER VAPOR  
IMAGERY OVER WESTERN MN EARLY THIS AFTERNOON. FAIRLY WIDESPREAD  
SNOW IS ACCOMPANYING THIS FEATURE OVER EASTERN MN, WITH 1-3SM  
VSBY PRETTY COMMON AND A FEW LESS THAN 1SM SNOW OBS. MOST  
GUIDANCE IS REALLY NOT HANDLING THIS FEATURE PARTICULARLY WELL,  
THOUGH RAP/NAMNEST APPEAR TO BE HANDLING IT THE BEST. HAVE  
INCREASED POPS TO LIKELY THIS EVENING OVER SOUTHWESTERN CWA  
WHERE RAP/NAMNEST ARE FAVORING THE BEST, ALBEIT STILL QUITE  
LIGHT QPF (JUST A HUNDREDTH OR TWO).  
 
THICKER STRATUS ASSOCIATED WITH THIS SNOW SHOWS UP QUITE NICELY  
ON VISIBLE SATELLITE IMAGERY, WITH RECENT SATELLITE TRENDS  
LEAVING ME A LITTLE CONCERNED THAT THIS LIGHT SNOW ACTIVITY  
COULD END UP A BIT FARTHER EAST AND DEEPER INTO OUR CWA THAN  
GUIDANCE WOULD SUGGEST. FOR NOW STRETCHED THE CHANCE POPS  
FARTHER EAST, BUT ONCOMING EVENING SHIFT WILL NEED TO CLOSELY  
MONITOR SATELLITE AND RADAR TRENDS AND MAY NEED TO TWEAK  
FORECAST ACCORDINGLY. THINKING ACCUMULATION SHOULD END UP AN  
INCH OR LESS, BUT WITH TEMPS BELOW FREEZING AND LINGERING ROAD  
TREATMENT PROBABLY MOSTLY WASHED AWAY, EVEN A COATING OF SNOW ON  
ROADS COULD CAUSE HAZARDOUS TRAVEL CONDITIONS.  
 
STRATUS DECK BLANKETS MOST OF THE WESTERN GREAT LAKES AND  
MIDWEST AND IS ALSO NOT BE HANDLED PARTICULARLY WELL BY MOST  
GUIDANCE. FORECAST SOUNDINGS MAINTAIN A FRONTAL INVERSION  
THROUGH THE NIGHT AND INTO TOMORROW MORNING WITH THIS STRATUS  
DECK TRAPPED BENEATH IT. LACKING ANY PARTICULARLY STRONG  
SUBSIDENCE, THE STRATUS SHOULD HANG ON THROUGH THE NIGHT, SO  
HAVE BUMPED UP CLOUD COVER AND TEMPS ACCORDINGLY IN THE GRIDS  
FOR TONIGHT.  
 
SHORTWAVE ON THE NOSE OF A 160KT 300MB JET HAVE PLOWED ONSHORE  
INTO SOUTHERN BRITISH COLUMBIA THIS MORNING. THIS FEATURE IS  
PROGGED TO ZIP ACROSS THE SOUTHERN CANADIAN ROCKIES TONIGHT  
BEFORE DIVING SOUTHEAST AROUND THE WESTERN FLANKS OF THE DEEP  
LONGWAVE TROUGH OVER THE GREAT LAKES AND EASTERN CANADA. THERE  
REMAIN SPLIT SOLUTIONS IN HANDLING THIS FEATURE, WITH MOST  
HI-RES/CAM GUIDANCE FAVORING A FARTHER NORTH TRACK WITH OUR CWA  
GROUND ZERO FOR THE HEAVIEST SNOWFALL. GLOBAL MODELS ON THE  
OTHER HAND ARE FARTHER SOUTH, WITH THE AXIS OF HIGHEST SNOWFALL  
TOTALS ACROSS CENTRAL IL. IN FACT, GFS AND ECMWF WOULD KEEP  
ACCUMULATING SNOW SOUTH OF THE CITY OF CHICAGO WITH A COUPLE OF  
INCHES OF ACCUMULATION ACROSS OUR FAR SOUTHERN AND SOUTHWESTERN  
CWA.  
 
GIVEN THIS SHORTWAVE WAS STILL OFFSHORE AT 12Z THIS MORNING, I  
TEND TO LEAN A BIT MORE TOWARD THE GLOBAL MODEL'S HANDLING OF  
THIS FEATURE. OF THE 3 BIG GLOBAL MODELS, THE GFS IS THE  
FARTHER NORTH AND HAVE LARGELY FOLLOWED THAT SOLUTION AS A BIT  
OF COMPROMISE. NBM POPS HAVE TRENDED DOWNWARD NORTHERN CWA AND  
THIS SEEMS REASONABLE, SO MADE NO ADJUSTMENTS TO NBM POPS.  
WHICH CONVEYS THE UNCERTAINLY WITH FARTHER NORTH CAM/HIRES  
GUIDANCE. IF GLOBAL MODELS DON'T SHIFT BACK NORTH, THEN POPS  
OVER NORTHERN CWA WILL NEED TO BE LOWERED IN SUBSEQUENT FORECAST  
UPDATES.  
 
- IZZI  
 
FRIDAY THROUGH WEDNESDAY:  
 
WITH GOOD AGREEMENT IN ALL ACCUMULATING SNOW LIKELY HAVING SHIFTED  
OUT OF THE AREA PRIOR TO DAYBREAK FRIDAY, POPS NUDGED DOWN TO  
SLIGHT CHANCE IN THE MORNING WILL PROBABLY BE ABLE TO BE REMOVED  
WITH LATER FORECASTS. A SHORT-WAVE ASSOCIATED WITH WEAK SURFACE  
LOW PRESSURE OVER LAKE SUPERIOR WILL PUSH ACROSS THE WESTERN  
LAKES IN THE AFTERNOON AND EARLY EVENING. THIS WAVE MAY BRING A  
GLANCING BLOW OF FLURRIES AND PERHAPS A FEW TRUE SNOW SHOWERS  
(~20% POPS) TO APPROXIMATELY THE NORTHEASTERN 1/2 OR 1/3 OF THE  
CWA TOWARDS AND AFTER SUNSET. THE COLD FRONT TRAILING FROM THE  
SURFACE LOW WILL BRING THE FIRST SHOT OF MODIFIED ARCTIC AIR FOR  
THE BITTERLY COLD WEEKEND IN STORE (MORE ON THAT BELOW).  
 
EXPANSIVE 1040+ MB ARCTIC HIGH PRESSURE WILL GRADUALLY SPREAD  
SOUTHEASTWARD FRIDAY THROUGH THE WEEKEND, FROM THE CANADIAN  
PRAIRIES FRIDAY, TO THE MID-UPPER MO RIVER VALLEY SATURDAY  
NIGHT, AND TO CENTRAL ILLINOIS AND INDIANA SUNDAY NIGHT. THE  
INITIAL COLD FRONT PASSAGE FRIDAY NIGHT WILL BRING LOWS IN THE  
SINGLE DIGITS AND LOWER TEENS AND WIND CHILLS OF ABOUT 0 TO 15  
BELOW. THE FINAL CLIPPER-LIKE SYSTEM IN THE PARADE OF THESE  
SYSTEMS OVER THE PAST 7-10 DAYS WILL LIKELY BRING A SWATH OF  
ACCUMULATING SNOW TO PORTIONS OF THE REGION DURING THE DAY ON  
SATURDAY, INTERACTING WITH A TIGHT LOWER TO MID-LEVEL BAROCLINIC  
ZONE IN PLACE (IMPLIED FRONTOGENESIS FOR ENHANCED MESOSCALE  
BANDING).  
 
SIMILAR TO THE THURSDAY NIGHT SYSTEM, THE SOUTHWARD SHIFT OF THE  
FOCUS FOR A POTENTIALLY PLOWABLE FLUFFY SNOWFALL IN RECENT MODEL  
CYCLES CONTINUED WITH THE 12Z GLOBAL ENSEMBLE GUIDANCE. WITH THIS  
IN MIND, THE HIGHEST POPS OF NEARLY 70% ARE FOCUSED NEAR/SOUTH OF  
THE ILLINOIS AND KANKAKEE RIVER VALLEYS. THAT SAID, FELT  
COMFORTABLE WITH LIKELY THRESHOLD (55-60%) POPS STILL UP TO THE  
I-88 CORRIDOR FOR A FEW KEY REASONS. LOW AMPLITUDE FEATURES LIKE  
SATURDAY'S ARE PRONE TO LARGER SHIFTS IN RELATIVELY SHORT LEAD  
TIMES IN THEIR MEANINGFUL QPF AND ACCUMULATING SNOW FOOTPRINTS.  
IN ADDITION, THERE'S STILL A RESPECTABLE % OF ENSEMBLE MEMBERS  
(ROUGH ESTIMATE OF ABOUT 30%) WITH THE FAVORED AXIS AS FAR NORTH  
AS THE CHICAGO METRO.  
 
ANOTHER IMPORTANT ITEM TO KEEP IN MIND IS THAT WITH SURFACE TEMPS  
IN THE SINGLE DIGITS AND TEENS, MUCH OF THE COLUMN WILL RESIDE IN  
THE DGZ, AND THUS IT WON'T TAKE MUCH FOR LIGHT SNOW TO BE WRUNG  
OUT. ALSO, NOTABLY FOR THIS ASPECT, WITH AIR TEMPS SO COLD, ROAD  
TREATMENTS ARE TYPICALLY RENDERED LESS EFFECTIVE AND OFTEN MAKE  
FOR WORSE TRAVEL IMPACTS WITH ONLY LIGHT AMOUNTS OF SNOW VS. WITH  
TEMPS CLOSER TO FREEZING (SUCH AS TODAY). WHEREVER THE ENHANCED  
MESOSCALE BANDING SETS UP, THE DEEP DGZ AND MORE FAVORABLY ALIGNED  
ASCENT THROUGH IT COULD CERTAINLY PRESENT A CHANCE FOR WELL ABOVE  
CLIMO 15-20:1 RATIOS AND ONLY MODEST QPF FLUFFING UP TO SEVERAL  
INCHES OF SNOW. EXPERIMENTAL PROBABILITIES BASED ON ENSEMBLE  
MEMBERSHIP CURRENTLY WOULD SUGGEST THE HIGHEST CHANCES OF THIS  
BEING SOMEWHERE ACROSS CENTRAL ILLINOIS AND INDIANA.  
 
REGARDLESS OF HOW THE SATURDAY DAYTIME SNOW PLAYS OUT (OR IF SOME  
AREAS ARE EVEN MISSED ALTOGETHER), THE SNOW COVER ACROSS THE  
REGION, APPROACHING ARCTIC HIGH, AND 850 MB TEMPS OF -15 TO -20C  
WILL SET THE STAGE FOR THE COLDEST NIGHT OF THE MONTH THUS FAR.  
SUSTAINED NORTHWEST WINDS OF 10-15 MPH AND TEMPS PLUNGING BELOW  
ZERO FOR MOST OF THE AREA (POSSIBLY NEAR -10F IN SPOTS WEST OF  
THE FOX VALLEY) WILL YIELD WIND CHILLS OF 15 TO 30 BELOW ZERO. A  
COLD WEATHER ADVISORY WILL LIKELY BE NEEDED FOR MOST OF, IF NOT  
THE ENTIRE CWA INTO SUNDAY MORNING.  
 
THE SURFACE HIGH WILL SLIDE EAST OVERHEAD ON SUNDAY, LIMITING  
MIXING HEIGHTS BUT ALSO BRINGING LIGHTER WINDS AS HIGHS REACH THE  
POSITIVE SINGLE DIGITS AND LOWER TEENS. THE SURFACE HIGH POSITION  
OVER CENTRAL IL SUNDAY EVENING WILL BE CLOSE ENOUGH FOR TEMPS TO  
TANK EVERYWHERE EXCEPT PROBABLY CHICAGO DESPITE ONSET OF WARM AIR  
ADVECTION ALOFT. EXPECT RECOVERY INTO THE 20S ON MONDAY AND THEN  
LOWS IN THE TEENS MONDAY NIGHT. THIS WILL BE MERELY A PRELUDE TO  
NOTABLY MILDER CONDITIONS EXPECTED THE REST OF NEXT WEEK WITH A  
CHANGE TO A ZONAL JET STREAM PATTERN. TEMPERATURES MAY APPROACH  
40F NEXT WEDNESDAY BARRING SUBSTANTIAL EFFECTS FROM LOW CLOUDS,  
WHICH IS POSSIBLE THIS TIME OF YEAR. CURRENT SIGNS POINT TO THE  
OVERALL MILDER PATTERN LINGERING TOWARDS CHRISTMAS. PRECIP  
CHANCES WILL REMAIN LOW THROUGH THE CURRENT DAY 7.  
 
CASTRO  
 

 
   
AVIATION /00Z TAFS THROUGH 06Z FRIDAY/
 
 
ISSUED AT 545 PM CST WED DEC 10 2025  
 
FORECAST CONCERNS FOR THE TERMINALS...  
 
- PERIOD OF LIGHT SNOW SHOWERS/FLURRIES THIS EVENING.  
 
- MVFR CEILINGS TO PREVAIL THROUGH TONIGHT BEFORE LIFTING  
THURSDAY AFTERNOON.  
 
- ANOTHER PERIOD OF ACCUMULATING SNOW THURSDAY EVENING AND  
NIGHT.  
 
WINDS WILL CONTINUE TO SUBSIDE THIS EVENING AS THE ATMOSPHERE  
DECOUPLES WITH GENERALLY 8-10 KT WINDS OVERNIGHT FROM THE  
NORTHWEST. HOWEVER, A SUBTLE DISTURBANCE IN EASTERN IA WILL  
PIVOT OVER NORTHERN IL AND PORTIONS OF NORTHWEST IN LATER THIS  
EVENING RESULTING IN A PERIOD OF LIGHT SNOW SHOWERS AND/OR  
FLURRIES. WHILE THE BETTER MOISTURE ALOFT IS FORECAST TO RESIDE  
CLOSER TO RFD AND WESTERN IL, IT SEEMS SUFFICIENT MOISTURE WILL  
BE PRESENT IN THE SNOW GROWTH REGION TO SUPPORT A 40-50% CHANCE  
FOR FLURRIES AS FAR EAST AS THE CHICAGO AREA TERMINALS. GIVEN  
THE LOWER COVERAGE OF ANY SNOW SHOWERS/FLURRIES HAVE OPTED TO  
INTRODUCE TEMPOS INTO THE TAFS. REGARDLESS, ANY ACCUMULATIONS  
FROM SAID SNOW IS EXPECTED TO BE MINIMAL WITH UP TO A DUSTING AT  
WORST MAINLY AT RFD.  
 
SNOW WILL TAPER SHORTLY AFTER MIDNIGHT TONIGHT WITH OTHERWISE  
DRY CONDITIONS EXPECTED FOR THE REST OF TONIGHT AND MUCH OF THE  
DAY ON THURSDAY. WHILE IT DOES LOOK AS IF CEILINGS WILL LIFT  
TOWARDS THE VFR RANGE BY THURSDAY AFTERNOON, SOME LOW-LEVEL  
MOISTURE IS FORECAST TO HANG AROUND WHICH MAY ALLOW SOME MVFR  
CLOUDS TO LINGER THROUGH THIS TIMEFRAME AS WELL. AS FOR WINDS,  
EXPECT DIRECTIONS TO BECOME MORE WEST-SOUTHWEST ON THURSDAY  
BEFORE SETTLING INTO AN EASTERLY DIRECTION THURSDAY EVENING.  
THOUGH SPEEDS WILL REMAIN LIGHT (AROUND 5-6 KTS) THROUGH THE  
PERIOD.  
 
FINALLY, ANOTHER DISTURBANCE WILL MOVE INTO NORTHERN IL AND  
NORTHWEST IN THURSDAY EVENING BRINGING WITH IT ANOTHER PERIOD OF  
ACCUMULATING SNOW. LATEST FORECAST GUIDANCE CONTINUES TO FAVOR  
AREAS SOUTH AND WEST OF A ROCHELLE, IL TO RENSSELAER, IN LINE AS  
GETTING THE MOST SNOWFALL (2-4+ INCH AMOUNTS) BUT THERE IS A  
GROWING SIGNAL FOR SOME BETTER FORCING TO GET AS FAR EAST AS THE  
CHICAGO TERMINALS. WITH THIS SIGNAL BEING SOMEWHAT PERSISTENT  
AMONG HI-RES GUIDANCE HAVE OPTED TO TREND 30-HOUR TAFS TOWARDS  
THIS POTENTIAL BY INTRODUCING MVFR VISIBILITIES AFTER 03Z  
THURSDAY EVENING. THAT SAID, IF CONFIDENCE GROWS MAY NEED TO  
CONSIDER LOWER VISIBILITIES. AS FOR AMOUNTS, IT APPEARS THE TAF  
SITES WILL LIKELY SEE SNOW TOTALS IN THE 1-2 INCH RANGE (1-3  
INCH CLOSER TO RFD) FROM THIS EVENT THOUGH LOCALLY HIGHER  
AMOUNTS COULD BE SEEN IF THE AFOREMENTIONED FORCING PANS OUT.  
 
YACK  
 

 
   
LOT WATCHES/WARNINGS/ADVISORIES
 
 
IL...NONE.  
IN...NONE.  
LM...SMALL CRAFT ADVISORY UNTIL 4 AM CST THURSDAY FOR WINTHROP  
HARBOR IL TO GARY IN.  
 
SMALL CRAFT ADVISORY UNTIL NOON CST THURSDAY FOR GARY TO BURNS  
HARBOR IN-BURNS HARBOR TO MICHIGAN CITY IN.  
 

 
 

 
 
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