A fast-moving upper-level disturbance tracked through central Illinois on December 19, 2009, bringing a period of light snow to the area. with higher amounts northwest of the Illinois River.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS ILX wrote it up.
A fast-moving upper-level disturbance tracked through central Illinois on December 19, 2009, bringing a period of light snow to the area. Total snowfall was generally around 1 inch...with higher amounts northwest of the Illinois River. Due to the light accumulation of snow, many area roads became slick and hazardous. As a result, a few traffic accidents were reported. The most serious accident involved a car on I-55 in Springfield that skidded off the road and hit a light post, killing the driver.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Lincoln, IL wrote its last area forecast discussion before the first event at Dec 18, 11:45 PM CST, 15 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 1145 PM CST FRI DEC 18 2009 .DISCUSSION... ISSUED 859 PM CST FRI DEC 18 2009 BAND OF LIGHT SNOW IS CONTINUING TO SLOWLY PIVOT EAST THROUGH THE FORECAST AREA. IT HAS HAD A TOUGH TIME MAKING PROGRESS INTO A DRIER LOW/MID LEVEL AIR MASS. THIS BAND OF SNOW IS ASSOCIATED WITH A WEAK DEFORMATION ZONE ASSOCIATED WITH A DEPARTING UPPER WAVE. HOWEVER...THE FORCING WITH THIS FEATURE HAS NOT BEEN AND IS NOT EXPECTED TO BECOME VERY STRONG. ALSO...DUE TO A MAJOR STORM SYSTEM STARTING TO WORK ITS WAY UP THE EAST COAST...IT DOES NOT HAVE MUCH MOISTURE TO WORK WITH. GOING FORECAST IS IN GOOD SHAPE OVERALL. ONLY PLAN ON MINOR TWEAKS FOR THE LATEST AND EXPECTED TRENDS. BAK && .AVIATION... ISSUED 1145 PM CST FRI DEC 18 2009 A WEAK TROF HAS PUSHED EAST OF THE CENTRAL ILLINOIS TERMINALS THIS EVENING...AND WINDS SHIFTED MORE NORTHERLY ON ITS BACK SIDE. WINDS WILL GRADUALLY TURN NORTHWEST ON SATURDAY AND INCREASE TO 10-15 KTS AS THE PRESSURE GRADIENT INCREASES. LOW LEVEL DRY AIR HAS DELAYED THE ARRIVAL OF THE SNOW...BUT IT IS CURRENTLY ALONG AND WEST OF HE I-55 CORRIDOR. THIS AREA OF SNOW...BEHIND THE SURFACE TROF...WILL PIVOT THROUGH THE TERMINAL AREA OVERNIGHT INTO EARLY SATURDAY. IFR CONDITIONS EXPECTED AS THE SNOW MOVES THROUGH. WHILE CONDITIONS WILL IMPROVE SOMEWHAT AS THE SNOW THREAT TAPERS OFF BY SATURDAY MORNING...EXPECT CIGS/VSBYS TO STAY IFR/LOW END MVFR THROUGH THE END OF THE 06Z TAF PERIOD. ANOTHER UPPER DISTURBANCE MOVING THROUGH MAY PRODUCE A FEW FLURRIES FOR MUCH OF SATURDAY...BUT HAVE ONLY CARRIED VCSH WITH THIS FEATURE AT THIS TIME. BAK && .PREV DISCUSSION... ISSUED 115 PM CST FRI DEC 18 2009 LATEST SURFACE ANALYSIS INDICATING AN INVERTED TROF SITUATION RIGHT ACROSS THE FORECAST AREA EARLY THIS AFTN. MOST OF THE PRECIP WAS OCCURRING ALONG AND WEST OF THE ILLINOIS RIVER VALLEY WITH A MIX OF RAIN AND SNOW...WITH MOSTLY SNOW FURTHER NW CLOSER TO GALESBURG. FURTHER SOUTH...A MUCH STRONGER SURFACE LOW WAS SITUATED ACRS THE FLORIDA PANHANDLE AND WILL TRACK NE AND BE THE MAIN WEATHER MAKER FOR AREAS TO OUR EAST OVR THE NEXT SEVERAL DAYS. STILL QUITE A BIT OF UNCERTAINTY WITH RESPECT TO THE MIDWEEK STORM WITH MODELS MUCH FURTHER NORTHWEST WITH THE SFC SYSTEM THAN YESTERDAY AT THIS TIME. SHORT TERM...TONIGHT THROUGH MONDAY MAIN FORECAST CONCERN WL BE WITH SNOW AMTS TNT...MAINLY ACRS THE WEST HALF...AND THE TIMING OF PRECIP ACRS OUR FAR EASTERN COUNTIES LATE TNT AS FORECAST SOUNDINGS ARE SLOW TO SATURATE THE LOW LEVELS UNTIL AFTR 06Z. NOT TOO MUCH TO CHOOSE FROM MODEL WISE DURING THIS TIME PERIOD AS THE INVERTED TROF BECOMES ABSORBED BY THE MUCH LARGER WEATHER SYSTEM TO OUR SOUTH LATER TNT INTO SATURDAY. MODELS CONTINUE TO INDICATE THE BEST MID LEVEL FORCING WL BE TO THE WEST AND NORTHWEST OF THE TROF WHICH WOULD BE WEST OF THE INTERSTATE 55 CORRIDOR. SNOW RATIOS RUNNING ARND 12:1 WHICH WOULD SUPPORT UP TO 2 INCHES WITH LIGHTER AMTS AS YOU HEAD EAST LATER TNT INTO SATURDAY MRNG. FORECAST SOUNDINGS CONTINUE TO INDICATE A VERY SLOW INCREASE IN MOISTURE AT THE LOW LEVELS ACRS OUR ERN COUNTIES WITH THE BEST SATURATION FOR PRECIP NOT OCCURRING UNTIL AFTR 06Z. AS THE MAIN UPPER ENERGY SHIFTS EAST OF THE AREA ON SATURDAY...WE SHOULD SEE A DECREASE IN THE COVERAGE OF THE PRECIP FROM WEST TO EAST DURING THE DAY WITH THE HIGHEST POPS ACRS THE EAST. FORECAST SOUNDINGS SHOWING WE LOSE THE ICE CRYSTAL GROWTH FOR SNOW LATE TMRW INTO TMRW NIGHT SUGGESTING THE POTENTIAL FOR A LITTLE FREEZING DRIZZLE. FOR NOW WL HOLD OFF MENTIONING THAT BUT WL HAVE TO KEEP AN EYE ON THAT POSSIBILITY. NEXT WEATHER SYSTEM WILL BE TRACKING QUICKLY SE INTO THE NRN PLAINS LATE SUNDAY AND LIKE THE SOLUTION FROM THE GFS IN A FURTHER SOUTH TRACK TO THE LOW...BUT STILL EXPECTED TO STAY WELL NORTH OF OUR AREA. THE BEST LAYERED FORCING SHOULD REMAIN NORTH OF THE TRACK OF THE LOW...WITH ONLY THE BETTER CHANCE FOR LIGHT SNOW REMAINING ACRS OUR NORTH...WITH PROGRESSIVELY LOWER POPS WARRANTED AS YOU HEAD SOUTH. WEAK HIGH PRESSURE WILL THEN SETTLE IN FOR EARLY NEXT WEEK IN THE WAKE OF THE CLIPPER SYSTEM WITH LITTLE IN THE WAY OF APPARENT WEATHER FOR OUR AREA. LONG TERM...TUESDAY THROUGH FRIDAY SIGNIFICANT MODEL DIFFERENCES CONTINUE WITH RESPECT TO THE MAJOR STORM SYSTEM EXPECTED TO TAKE SHAPE ACRS THE PLAINS ON LATE TUESDAY INTO WEDNESDAY. YESTERDAY...THE SPLIT FLOW PATTERN SHOWED NO SIGNS OF ANY PHASING WHICH KEPT THE STRONG SFC LOW WELL SOUTH OF OUR AREA. WITH THE 00Z RUN OF THE ECMWF AND 06Z RUN OF THE OPERATIONAL GFS...THERE WAS A SIGNIFICANT CHANGE AS BOTH MODELS SHOWED SOME PHASING OF THE NRN AND SRN STREAMS ACRS THE PLAINS...WHICH EFFECTIVELY PUSHED THE LOW MUCH FURTHER TO THE WEST OF THE PREVIOUS TRACK YESTERDAY. THE LATEST CANADIAN MODEL HAS SHIFTED MUCH FURTHER NORTHWEST WITH THE STORM AS WELL. THE CLOSED SYSTEM THEN SLOWS DOWN TO A CRAWL LATER IN THE WEEK WHICH WOULD KEEP RAIN OR SNOW CHANCES GOING INTO THE WEEKEND. FOR NOW...WITH AS MUCH MODEL SPREAD AS THERE IS WITH THIS SYSTEM...WOULD PREFER TO KEEP THE CURRENT EXTENDED FORECAST AS IS WITH SOME MINOR ADJUSTMENTS IN TEMPERATURE AND PRECIP TIMING. WILL KEEP THE CHANCES FOR SNOW EXCPT IN THE SOUTH WHERE A MIX OF RAIN AND SNOW LOOKS MORE LIKELY. HOWEVER...IF THE FURTHER NW TREND CONTINUES WITH THE LATER MODEL RUNS...WL HAVE TO MAKE SOME SIG CHANGES TO THE PRECIP TYPE AND TEMPS FOR THE WED THRU AT LEAST XMAS DAY. AS MENTIONED YESTERDAY...THIS SYSTEM STILL HAS THE POTENTIAL TO BE A HIGH IMPACT EVENT FOR OUR AREA...WITH THE THREATS RANGING FROM HEAVY SNOW TO OUR NORTHWEST...TO HEAVY RAIN ACRS THE SOUTH AND EVEN THE THREAT FOR FREEZING RAIN FOR A TIME...ESP ACRS THE NORTH AS THE STORM SYSTEM HEADS IN OUR DIRECTION ON WED. STAY TUNED. SMITH && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LINCOLN IL 403 PM CST FRI DEC 18 2009 ILZ027>031-036>038-040-041-191200- FULTON-KNOX-MARSHALL-MASON-MCLEAN-PEORIA-SCHUYLER-STARK-TAZEWELL- WOODFORD- 403 PM CST FRI DEC 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL ILLINOIS. .DAY ONE...TONIGHT LIGHT SNOW WILL BECOME WIDESPREAD ALONG AND WEST OF THE ILLINOIS RIVER BY THIS EVENING. THE SNOW WILL CONTINUE OVERNIGHT...WITH AROUND 1 INCH OF ACCUMULATION BY SATURDAY MORNING. THIS WILL CREATE SLIPPERY CONDITIONS ON UNTREATED ROADS...PARTICULARLY THIS EVENING THROUGH TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY LIGHT SNOW SATURDAY MORNING WILL DIMINISH TO FLURRIES BY AFTERNOON. AREA ROADS MAY STILL BE SLICK IN SPOTS. THE NEXT CHANCE FOR SNOW WILL BE LATE WEDNESDAY NIGHT AND INTO CHRISTMAS EVE. AS A RESULT...PEOPLE PLANNING HOLIDAY TRAVEL ARE ADVISED TO STAY INFORMED OF THE LATEST FORECASTS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. ILZ047>051-191200- CASS-MENARD-MORGAN-SANGAMON-SCOTT- 403 PM CST FRI DEC 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL ILLINOIS. .DAY ONE...TONIGHT A MIX OF LIGHT RAIN AND SNOW BEGINING EARLY THIS AFTERNOON WILL CHANGE TO ALL SNOW THIS EVENING. THE SNOW WILL CONTINUE OVERNIGHT...WITH 1 TO 2 INCHES OF ACCUMULATION BY SATURDAY MORNING. THIS WILL CREATE SLIPPERY CONDITIONS ON UNTREATED ROADS...PARTICULARLY TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY LIGHT SNOW SATURDAY MORNING WILL DIMINISH TO FLURRIES BY AFTERNOON. AREA ROADS MAY STILL BE SLICK IN SPOTS. THE NEXT CHANCE FOR SNOW WILL BE LATE WEDNESDAY NIGHT AND INTO CHRISTMAS EVE. AS A RESULT...PEOPLE PLANNING HOLIDAY TRAVEL ARE ADVISED TO STAY INFORMED OF THE LATEST FORECASTS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. ILZ042>046-052>057-061-191200- CHAMPAIGN-CHRISTIAN-COLES-DE WITT-DOUGLAS-EDGAR-LOGAN-MACON- MOULTRIE-PIATT-SHELBY-VERMILION- 403 PM CST FRI DEC 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL ILLINOIS AND EAST CENTRAL ILLINOIS. .DAY ONE...TONIGHT A MIX OF LIGHT RAIN AND SNOW BEGINING EARLY THIS AFTERNOON WILL CHANGE TO ALL SNOW THIS EVENING. THE SNOW WILL CONTINUE OVERNIGHT...WITH UP TO 1 INCH OF ACCUMULATION BY SATURDAY MORNING...LESS THAN AN INCH EAST OF INTERSTATE 57. THIS WILL CREATE SLIPPERY CONDITIONS ON UNTREATED ROADS...PARTICULARLY TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY LIGHT SNOW SATURDAY MORNING WILL DIMINISH TO FLURRIES BY AFTERNOON. AREA ROADS MAY STILL BE SLICK IN SPOTS. THE NEXT CHANCE FOR SNOW WILL BE LATE WEDNESDAY NIGHT AND INTO CHRISTMAS EVE. AS A RESULT...PEOPLE PLANNING HOLIDAY TRAVEL ARE ADVISED TO STAY INFORMED OF THE LATEST FORECASTS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. ILZ071-072-191200- CLAY-RICHLAND- 403 PM CST FRI DEC 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ILLINOIS. .DAY ONE...TONIGHT THE LITTLE WABASH RIVER AT CLAY CITY WILL REMAIN ABOVE FLOOD STAGE FOR THE NEXT FEW DAYS. A MIX OF LIGHT RAIN AND SNOW BY THIS EVENING WILL CHANGE TO ALL SNOW OVERNIGHT. MINOR ACCUMULATIONS LESS THAN ONE HALF INCH ARE EXPECTED BY SATURDAY MORNING. THIS WILL CREATE A FEW SLIPPERY SPOTS ON UNTREATED ROADS...PARTICULARLY OVERNIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY LIGHT SNOW SATURDAY WILL DIMINISH TO FLURRIES BY EVENING. LITTLE ACCUMULATION IS ANTICIPATED...HOWEVER AREA ROADS MAY STILL BE SLICK IN SPOTS. THE NEXT CHANCE FOR SNOW WILL BE LATE WEDNESDAY NIGHT AND INTO CHRISTMAS EVE. AS A RESULT...PEOPLE PLANNING HOLIDAY TRAVEL ARE ADVISED TO STAY INFORMED OF THE LATEST FORECASTS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. ILZ062-063-066>068-073-191200- CLARK-CRAWFORD-CUMBERLAND-EFFINGHAM-JASPER-LAWRENCE- 403 PM CST FRI DEC 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL ILLINOIS AND SOUTHEAST ILLINOIS. .DAY ONE...TONIGHT A MIX OF LIGHT RAIN AND SNOW BY LATE THIS AFTERNOON WILL CHANGE TO ALL SNOW LATER THIS EVENING. THE SNOW WILL CONTINUE OVERNIGHT...WITH ACCUMULATIONS GENERALLY LESS THAN A HALF INCH BY SATURDAY MORNING. THIS WILL CREATE SLIPPERY SPOTS ON UNTREATED ROADS...PARTICULARLY OVERNIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY LIGHT SNOW SATURDAY WILL DIMINISH TO FLURRIES BY EVENING. LITTLE ACCUMULATION IS ANTICIPATED...HOWEVER AREA ROADS MAY STILL BE SLICK IN SPOTS. THE NEXT CHANCE FOR SNOW WILL BE LATE WEDNESDAY NIGHT AND INTO CHRISTMAS EVE. AS A RESULT...PEOPLE PLANNING HOLIDAY TRAVEL ARE ADVISED TO STAY INFORMED OF THE LATEST FORECASTS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED. DPK
The national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Due to icy road conditions, a car skidded off I-55 in Springfield near the Sangamon Avenue exit at 6:10 AM. The car struck a light post, killing the driver.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Winter Weather, Sangamon | 2009-12-19 | 78 | Male | Vehicle/Towed Trailer | Indirect |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2009Every state in 2009This day in weather historyWarnings in Illinois, December 2009
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 205300.