A fairly long duration snow was seen across far northern Illinois from the late afternoon on the 23rd through the morning of the 24th. The surface low pressure center of this system actually passed well to our south, but the upper level low, strong mid-level winds and the associated favorable dynamics, and even some elevated instability passed over the area.
Snow began in the afternoon of the 23rd across northern Illinois, at times falling as very large and wet aggregate flakes. This would change back to rain or drizzle in many areas, except for much of McHenry and Lake Counties, where the precipitation type generally remained as snow into the night. A radar image of the initial snow band during the late afternoon can be seen below.
As the upper level low pressure approached, precipitation spread back east and south across almost the entire area. With the cooling atmosphere, this would mainly be all snow through much of the overnight and into early morning on the 24th. At times this was moderate in intensity, and such an area can be seen in the radar image below across Lake and northern Cook County, as well as Kane into DeKalb Counties. Lightning was reported in Boone County a few hours prior to this.
Visible Satellite Image of the Snow Cover from February 25th |
Snowfall Totals
NWS Cooperative Observer Precipitation Amounts (Liquid Equivalents) |
Regional Snowfall Map |
NWS Cooperative and CoCoRaHS Snowfall Reports
PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE CHICAGO IL 1000 AM CST FRI FEB 24 2012 ...MORNING SNOWFALL ROUNDUP... THE FOLLOWING ARE SNOW AMOUNTS FOR THE PREVIOUS 24-HOURS. OBSERVATIONS ARE USUALLY TAKEN AT 7 AM. REPORTS FROM NWS COOPERATIVE OBSERVERS AND COCORAHS OBSERVERS. 24-HOUR SNOWFALL AMOUNTS FOR FRIDAY(02/24/12)... NORTHERN ILLINOIS SNOW LOCATION (COUNTY): FALL(INCHES) BULL VALLEY 2WNW (MCHENRY)....................9.3 CARY 2NE (MCHENRY)............................8.5 MUNDELEIN (LAKE)..............................8.2 LAKE ZURICH (LAKE)............................8.0 WOODSTOCK 5NW (MCHENRY).......................7.8 GURNEE 2W (LAKE)..............................7.5 ROCKTON 1ESE (WINNEBAGO)......................7.5 MARENGO (MCHENRY).............................7.5 SPRING GROVE 2N (MCHENRY).....................7.5 GENOA (DE KALB)...............................7.3 GURNEE 2NE (LAKE).............................7.3 HARVARD (MCHENRY).............................7.0 LAKE VILLA 1SSW (LAKE)........................7.0 HAWTHORN WOODS 1N (LAKE)......................7.0 BEACH PARK 1W (LAKE)..........................6.7 WAUCONDA (LAKE)...............................6.7 BELVIDERE (BOONE).............................6.5 HOFFMAN ESTATES 5W (COOK).....................6.5 HUNTLEY 4W (MCHENRY)..........................6.5 INVERNESS 2S (COOK)...........................6.4 ROSCOE 2ESE (WINNEBAGO).......................6.1 ROSCOE 2SE (WINNEBAGO)........................6.1 BARRINGTON (LAKE).............................5.9 PALATINE 1E (COOK)............................5.9 ST. CHARLES 6NW (KANE)........................5.6 RIVERWOODS (LAKE).............................5.5 LAKEMOOR 2SE (LAKE)...........................5.5 BYRON 3N (OGLE)...............................5.3 LINCOLNSHIRE 1N (LAKE)........................5.2 ELGIN (KANE)..................................5.1 CRYSTAL LAKE (MCHENRY)........................5.0 MOUNT MORRIS (OGLE)...........................4.9 WAUKEGAN 2N (LAKE)............................4.8 ROCKFORD (WINNEBAGO)..........................4.8 ROCKFORD 4NW (WINNEBAGO)......................4.8 CORTLAND (DE KALB)............................4.6 ST CHARLES (KANE).............................4.5 ELGIN (KANE)..................................4.4 BOTANIC GARDENS (COOK)........................4.3 GENEVA 1SSW (KANE)............................4.3 DE KALB (DE KALB).............................4.2 WINFIELD (DU PAGE)............................4.2 SCHAUMBURG 2E (COOK).........................4.1 ELBURN (KANE).................................4.0 NORTH AURORA 2NE (KANE).......................4.0 ASHTON (LEE)..................................4.0 ROCKFORD 1NW (WINNEBAGO)......................4.0 SHABBONA (DE KALB)............................4.0 HANOVER PARK 2SSW (DU PAGE)...................3.8 ELK GROVE VILLAGE 1ESE (COOK).................3.6 ST CHARLES 7NW (KANE).........................3.2 NAPERVILLE 1NW (DU PAGE)......................3.1 BATAVIA 2WNW (KANE)...........................3.1 BATAVIA (KANE)................................3.0 ELK GROVE VILLAGE 2WSW (COOK).................3.0 PAW PAW (LEE).................................3.0 LOMBARD 1NNW (DU PAGE)........................2.8 SHERIDAN (LA SALLE)...........................2.8 MENDOTA 1N (LA SALLE).........................2.8 SUGAR GROVE 1NE (KANE)........................2.7 CAROL STREAM (DU PAGE)........................2.6 OHARE (COOK)..................................2.6 LISLE MORTON ARB (DU PAGE)....................2.6 WESTMONT 1SSE (DU PAGE).......................2.5 DOWNERS GROVE 2SE (DU PAGE)...................2.5 MARSEILLES 6WNW (LA SALLE)....................2.5 LA SALLE (LA SALLE)...........................2.4 YORKVILLE 2SE (KENDALL).......................2.4 LINCOLNWOOD 2E (COOK).........................2.3 WEST CHICAGO (DU PAGE)........................2.2 MONTGOMERY 1SSE (KENDALL).....................2.2 YORKVILLE 1NE (KENDALL).......................2.2 BATAVIA 1WNW (KANE)...........................2.1 OAK PARK 1NNE (COOK)..........................2.0 MENDOTA (LA SALLE)............................2.0 SENECA 2SSW (LA SALLE)........................1.8 OAK PARK 2S (COOK)............................1.5 LA GRANGE PARK 1SSW (COOK)....................1.5 LISLE (DU PAGE)...............................1.5 OSWEGO 5SSE (KENDALL).........................1.5 OTTAWA 2N (LA SALLE)..........................1.5 BURR RIDGE 2SW (DU PAGE)......................1.2 HOMER GLEN 1ENE (WILL)........................1.2 PLAINFIELD (WILL).............................1.2 COUNTRYSIDE 1ENE (COOK).......................1.0 AURORA 4SE (DU PAGE)..........................1.0 HOMER GLEN 4WNW (WILL)........................1.0 PLAINFIELD 1SW (WILL).........................1.0 MIDWAY 3SW (COOK).............................1.0 OTTAWA (LA SALLE).............................1.0 ROMEOVILLE (WILL).............................0.9 NEWARK (KENDALL)..............................0.9 OTTAWA 1NW (LA SALLE).........................0.8 MARSEILLES (LA SALLE).........................0.8 MANHATTAN 5ENE (WILL).........................0.7 JOLIET 2N (WILL)..............................0.7 MANHATTAN (WILL)..............................0.7 MARSEILLES 3NW (LA SALLE).....................0.6 NEW LENOX 2SE (WILL)..........................0.6 BRIDGEVIEW 1NNW (COOK)........................0.5 CHICAGO 6ESE (COOK)...........................0.5 ORLAND HILLS 1S (COOK)........................0.5 MINOOKA (GRUNDY)..............................0.5 AMBOY (LEE)...................................0.5 COAL CITY 4NNW (GRUNDY).......................0.4 CHICAGO RIDGE (COOK)..........................0.4 WORTH (COOK)..................................0.4 JOLIET 1.1N (WILL)............................0.4 COAL CITY (GRUNDY)............................0.3 CRETE 3E (WILL)...............................0.3 ROCHELLE (OGLE)...............................0.3 BURNHAM-HEGEWISCH 2NNW (COOK).................0.2 MONEE (WILL)..................................0.2 PEOTONE (WILL)................................0.1 PEOTONE (WILL)................................0.1 STREATOR (LIVINGSTON).........................0.1 BOURBONNAIS (KANKAKEE)......................TRACE DRESDEN LOCK/DAM (GRUNDY)...................TRACE DWIGHT (LIVINGSTON).........................TRACE PAXTON (FORD)...............................TRACE WATSEKA 5W (IROQUOIS).......................TRACE SENECA 1NE (LA SALLE).......................TRACE JOLIET LOCK/DAM (WILL)......................TRACE PARK FOREST (COOK)..........................TRACE PONTIAC (LIVINGSTON)........................TRACE NORTHWEST INDIANA SNOW LOCATION (COUNTY): FALL(INCHES) VALPARAISO 5NNE (PORTER)......................0.8 VALPARAISO 5NNE (PORTER)......................0.8 CROWN POINT 8E (PORTER).......................0.6 PORTAGE 1ESE (PORTER).........................0.6 VALPARAISO 1SE (PORTER).......................0.4 PORTER 1S (PORTER)............................0.4 DYER 1WNW (LAKE)..............................0.3 SCHERERVILLE 2WSW (LAKE)......................0.3 CROWN POINT 2WSW (LAKE).......................0.3 HEBRON 4NE (PORTER)...........................0.2 LAKES OF THE FOUR SEASONS 2NNE (PORTER).......0.2 VALPARAISO 6WSW (PORTER)......................0.2 VALPARAISO 2N (PORTER)........................0.2 VALPARAISO 1NNW (PORTER)......................0.1 WHEATFIELD 3S (JASPER)......................TRACE CROWN POINT 1N (LAKE).......................TRACE ST. JOHN (LAKE).............................TRACE VALPARAISO 4SW (PORTER).....................TRACE VALPARAISO 1ENE (PORTER)....................TRACE $$
Additional Reports
PRELIMINARY LOCAL STORM REPORT...SUMMARY NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 504 PM CST FRI FEB 24 2012 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 0553 AM SNOW DOWNERS GROVE 41.80N 88.02W 02/24/2012 M2.8 INCH DUPAGE IL CO-OP OBSERVER UPDATED REPORT. STILL SNOWING. 0553 AM SNOW ROSCOE 42.42N 89.01W 02/24/2012 M5.5 INCH WINNEBAGO IL BROADCAST MEDIA RELAYED BY MEDIA 0553 AM SNOW STILLMAN VALLEY 42.10N 89.18W 02/24/2012 E5.0 INCH OGLE IL BROADCAST MEDIA RELAYED BY MEDIA 0600 AM SNOW MCHENRY 42.34N 88.29W 02/24/2012 M7.3 INCH MCHENRY IL COCORAHS 7 ON GROUND 0600 AM SNOW DUPAGE AIRPORT 41.92N 88.25W 02/24/2012 M2.2 INCH DUPAGE IL ASOS 0600 AM SNOW CAPRON 42.40N 88.74W 02/24/2012 M4.9 INCH BOONE IL TRAINED SPOTTER 0608 AM SNOW CAPRON 42.40N 88.74W 02/24/2012 E5.0 INCH BOONE IL BROADCAST MEDIA RELAYED BY MEDIA 0616 AM SNOW ROCKFORD 42.27N 89.06W 02/24/2012 M5.5 INCH WINNEBAGO IL BROADCAST MEDIA AT WREX 0621 AM SNOW WADSWORTH 42.44N 87.92W 02/24/2012 M6.5 INCH LAKE IL BROADCAST MEDIA 0630 AM SNOW 3 S BARRINGTON 42.11N 88.13W 02/24/2012 M7.2 INCH COOK IL TRAINED SPOTTER STORM TOTAL SO FAR 0635 AM SNOW CHICAGO 41.88N 87.63W 02/24/2012 M2.0 INCH COOK IL BROADCAST MEDIA AT WGN-TV 0637 AM SNOW NAPERVILLE 41.76N 88.15W 02/24/2012 M2.0 INCH DUPAGE IL TRAINED SPOTTER 0644 AM SNOW WINNEBAGO 42.27N 89.24W 02/24/2012 M5.0 INCH WINNEBAGO IL BROADCAST MEDIA RELAYED BY MEDIA 0644 AM SNOW ROCHELLE 41.92N 89.06W 02/24/2012 M5.0 INCH OGLE IL BROADCAST MEDIA RELAYED BY MEDIA 0644 AM SNOW FRANKLIN GROVE 41.84N 89.30W 02/24/2012 M4.0 INCH LEE IL BROADCAST MEDIA RELAYED BY MEDIA 0645 AM SNOW 5 NNE ADDISON 42.00N 87.98W 02/24/2012 M3.6 INCH COOK IL COCORAHS 0654 AM SNOW FORRESTON 42.13N 89.58W 02/24/2012 E6.5 INCH OGLE IL BROADCAST MEDIA RELAYED BY MEDIA 0700 AM SNOW WOODSTOCK 42.31N 88.44W 02/24/2012 M8.3 INCH MCHENRY IL TRAINED SPOTTER 0715 AM SNOW S CHICAGO 41.87N 87.63W 02/24/2012 M0.3 INCH COOK IL NWS EMPLOYEE 0716 AM SNOW OREGON 42.01N 89.34W 02/24/2012 M5.5 INCH OGLE IL BROADCAST MEDIA RELAYED BY MEDIA 0722 AM SNOW 5 S PECATONICA 42.24N 89.36W 02/24/2012 M6.5 INCH WINNEBAGO IL BROADCAST MEDIA SNOW MEASURED IN SEWARD 0730 AM SNOW ISLAND LAKE 42.28N 88.20W 02/24/2012 M6.7 INCH LAKE IL TRAINED SPOTTER 0800 AM SNOW MORTON GROVE 42.04N 87.79W 02/24/2012 M2.6 INCH COOK IL TRAINED SPOTTER 0811 AM SNOW CARPENTERSVILLE 42.12N 88.27W 02/24/2012 M5.1 INCH KANE IL TRAINED SPOTTER 0815 AM SNOW ROSCOE 42.42N 89.01W 02/24/2012 M6.7 INCH WINNEBAGO IL BROADCAST MEDIA 0830 AM SNOW HUNTLEY 42.17N 88.42W 02/24/2012 M8.5 INCH MCHENRY IL COCORAHS STORM TOTAL. DELAYED REPORT. 0834 AM SNOW ELK GROVE VILLAGE 42.01N 87.99W 02/24/2012 M2.5 INCH COOK IL TRAINED SPOTTER 0839 AM SNOW CHERRY VALLEY 42.24N 88.96W 02/24/2012 M6.5 INCH WINNEBAGO IL BROADCAST MEDIA RELAYED BY MEDIA 0844 AM SNOW HAWTHORN WOODS 42.22N 88.06W 02/24/2012 M6.0 INCH LAKE IL TRAINED SPOTTER 0855 AM SNOW WADSWORTH 42.44N 87.92W 02/24/2012 M8.5 INCH LAKE IL BROADCAST MEDIA 0900 AM SNOW WARRENVILLE 41.82N 88.19W 02/24/2012 M2.9 INCH DUPAGE IL TRAINED SPOTTER 0900 AM SNOW 3 S BARRINGTON 42.11N 88.13W 02/24/2012 M7.4 INCH COOK IL TRAINED SPOTTER 0900 AM SNOW ELBURN 41.89N 88.47W 02/24/2012 M4.7 INCH KANE IL TRAINED SPOTTER 0929 AM SNOW EVANSTON 42.05N 87.69W 02/24/2012 M2.0 INCH COOK IL TRAINED SPOTTER 0930 AM SNOW E HARVARD 42.42N 88.61W 02/24/2012 M5.6 INCH MCHENRY IL COCORAHS 1140 AM SNOW 3 SW MIDWAY AIRPORT 41.75N 87.79W 02/24/2012 M1.7 INCH COOK IL CO-OP OBSERVER SNOW DEPTH 1 INCH 1219 PM SNOW ROCKFORD AIRPORT 42.20N 89.10W 02/24/2012 M5.0 INCH WINNEBAGO IL OFFICIAL NWS OBS STORM TOTAL 1219 PM SNOW ROMEOVILLE 41.65N 88.09W 02/24/2012 M1.0 INCH WILL IL OFFICIAL NWS OBS 1219 PM SNOW OHARE AIRPORT 41.98N 87.90W 02/24/2012 M3.5 INCH COOK IL OFFICIAL NWS OBS STORM TOTAL && $$