Fast Facts

• A low pressure system that reached a record strength in the lower Ohio Valley (reference NWS Paducah, KY) brought widespread impacts to the southern, central, and eastern United States on the night of March 2 through the morning of March 4.

• In the local area, heavy snowfall rates materialized south of I-80, with 1 to 2 inch per hour rates that were occasionally accompanied by lightning and thunder (rare thundersnow!). Total accumulations at most locations that saw snow ended up ranging from around 2 to a little over 5 inches.

• There were also strong winds ahead of and during the snow, especially south of the Kankakee River Valley, where gusts exceeded 45 mph.

• Resulting impacts were snow-covered roads and low visibility, with hazardous to at times dangerous travel south of I-80, including near and along I-57 and I-65.

I-57 in Kankakee County shortly after 3 PM CST on March 3, 2023 (courtesy of IDOT)

Fowler, IN in Benton County near 5 PM CST on March 3, 2023 (courtesy of INDOT)

• The event resulted in a sharp gradient of snowfall on its northern end, and the width of the snow corridor itself was only ~90 miles. The sharp gradient in snowfall and impacts was expected, however, pinpointing where exactly this would occur was challenging for forecasters leading up to this event (see Forecast Thoughts tab). 

• A Winter Storm Watch had been issued for northwest Indiana and a large part of northern Illinois Thursday morning, March 2. This was upgraded to a Warning for northwest Indiana and the Kankakee River Valley region of northern Illinois on Thursday evening, with an Advisory issued to the immediate northwest. When it became apparent that snowfall would not make it into some of that Advisory area, such as downtown Chicago and the western suburbs, the Advisory was cancelled for those locations on Friday morning.

Snow Totals

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE CHICAGO IL
1114 AM CST SAT MAR 4 2023 /1214 PM EST SAT MAR 4 2023/

...MARCH 3 2023 OBSERVED SNOWFALL REPORTS...

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURES. WE THANK ALL VOLUNTEER WEATHER OBSERVERS 
FOR THEIR DEDICATION. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

DO NOTE THERE WAS LIKELY SOME COMPACTING OF THE SNOWFALL FROM
WHEN IT ENDED FRIDAY EVENING TO THE SATURDAY MORNING OBSERVATIONS.

LOCATION                     AMOUNT    TIME/DATE       PROVIDER  
---------------------------------------------------------------           

...ILLINOIS...

...COOK COUNTY...
CHICAGO HEIGHTS              3.2 IN    0700 PM 03/03   PUBLIC               
HOMEWOOD                     2.0 IN    0700 PM 03/03   PUBLIC               
LANSING                      1.9 IN    0700 AM 03/04   COOP                 
PARK FOREST                  1.5 IN    0500 AM 03/04   COOP                 
OAK FOREST 1 NNW             0.5 IN    0700 AM 03/04   COCORAHS             

...FORD COUNTY...
MELVIN                       3.0 IN    0400 PM 03/03   BROADCAST MEDIA      

...GRUNDY COUNTY...
2 SE MAZON                   1.5 IN    0700 AM 03/04   COCORAHS             
CARBON HILL 3 NNW            0.8 IN    0700 AM 03/04   COCORAHS             
COAL CITY 4 NNW              0.4 IN    0700 AM 03/04   UCOOP                

...IROQUOIS COUNTY...
CHEBANSE                     4.5 IN    0500 PM 03/03   PUBLIC               
CRESCENT CITY 2 N            4.1 IN    0600 AM 03/04   COCORAHS             
THAWVILLE                    4.0 IN    0730 PM 03/03   PUBLIC               
ASHKUM 6 E                   3.0 IN    0700 AM 03/04   COCORAHS             

...KANKAKEE COUNTY...
GRANT PARK                   4.5 IN    0700 PM 03/03   PUBLIC               
ST. ANNE                     4.0 IN    0700 AM 03/04   COOP                 
KANKAKEE 1.4 WSW             3.5 IN    0600 AM 03/04   COCORAHS             
BRADLEY 0.7 SW               2.3 IN    0600 AM 03/04   COCORAHS             
HERSCHER 3 E                 1.2 IN    0745 AM 03/04   COCORAHS             
MANTENO                      1.0 IN    0700 PM 03/03   PUBLIC               

...LIVINGSTON COUNTY...
CHATSWORTH                   3.0 IN    0700 AM 03/04   COOP               
DWIGHT                       3.0 IN    0700 AM 03/04   COOP                 
EMINGTON                     2.8 IN    0730 PM 03/03   PUBLIC               

...WILL COUNTY...
PEOTONE                      2.1 IN    0600 PM 03/03   CO-OP OBSERVER       
CRETE 3 E                    2.0 IN    0700 AM 03/04   COCORAHS             
MONEE 5 SE                   2.0 IN    0800 AM 03/04   COCORAHS             
NEW LENOX 1 SSE              0.8 IN    0700 AM 03/04   COCORAHS             
MANHATTAN 5 ENE              0.8 IN    0800 AM 03/04   COOP                 
FRANKFORT                    0.5 IN    0700 PM 03/03   PUBLIC               
MOKENA 2 WSW                 0.5 IN    0700 AM 03/04   COCORAHS             


...INDIANA...

...JASPER COUNTY...
DEMOTTE                      5.3 IN    0700 PM 03/03   PUBLIC               
6 E FAIR OAKS                5.0 IN    0700 PM 03/03   PUBLIC               
DEMOTTE                      3.8 IN    0600 AM 03/04   COCORAHS             
DE MOTTE 6 S                 3.5 IN    0700 AM 03/04   COCORAHS             
DEMOTTE                      3.5 IN    0800 AM 03/04   COCORAHS             
ROSELAWN 3 ENE               2.0 IN    0700 AM 03/04   COCORAHS             
REMINGTON                    1.2 IN    0800 AM 03/04   COCORAHS             
RENSSELAER 2 SW              1.1 IN    0730 AM 03/04   COOP                 

...LAKE COUNTY...
CEDAR LAKE                   4.3 IN    0700 PM 03/03   PUBLIC               
MERRILLVILLE                 3.8 IN    0700 PM 03/03   PUBLIC               
CROWN POINT                  3.5 IN    0700 PM 03/03   PUBLIC               
HOBART 2.4 SE                2.5 IN    0914 AM 03/04   COCORAHS             
DYER                         2.0 IN    0700 AM 03/04   COCORAHS             
ST. JOHN 3 SSE               1.5 IN    0700 AM 03/04   COCORAHS                           
ST. JOHN                     1.4 IN    0600 AM 03/04   COCORAHS             
GARY                         0.5 IN    0645 PM 03/03   PUBLIC               

...NEWTON COUNTY...
ROSELAWN                     4.0 IN    0730 PM 03/03   PUBLIC               
BROOK                        3.0 IN    0700 PM 03/03   PUBLIC               
MOUNT AYR 2 NNE              2.6 IN    0830 AM 03/04   COCORAHS             
MOROCCO                      2.0 IN    0600 AM 03/04   COOP                 

...PORTER COUNTY...
HEBRON                       5.0 IN    0700 PM 03/03   PUBLIC               
2 NW KOUTS                   5.0 IN    0700 PM 03/03   PUBLIC               
VALPARAISO                   5.0 IN    0730 PM 03/03   PUBLIC               
VALPARAISO                   4.0 IN    0739 AM 03/04   COCORAHS                          
VALPARAISO 1 N               3.5 IN    0700 AM 03/04   COCORAHS             
BOONE GROVE 4 NNE            3.0 IN    0700 AM 03/04   COCORAHS             
VALPARAISO 4 SW              2.1 IN    0700 AM 03/04   COCORAHS             
PORTER                       1.9 IN    0700 AM 03/04   COCORAHS             
1 SW BURNS HARBOR            1.8 IN    0620 PM 03/03   TRAINED SPOTTER      
CHESTERTON 2 E               1.2 IN    0630 AM 03/04   COCORAHS             
WANATAH                      1.2 IN    0700 AM 03/04   COOP                 
OGDEN DUNES                  1.0 IN    0600 AM 03/04   COCORAHS             

Winds

PUBLIC INFORMATION STATEMENT...UPDATED
NATIONAL WEATHER SERVICE CHICAGO IL
1113 AM CST SAT MAR 4 2023 /1213 PM EST SAT MAR 4 2023/

...HIGHEST WIND GUST REPORTS ON FRIDAY MARCH 3RD...

LOCATION                     SPEED     TIME/DATE                            
3 WNW PONTIAC                53 MPH    1239 PM 03/03
PAXTON                       53 MPH    1239 PM 03/03                        
1.7 E REMINGTON (INDOT)      49 MPH    0339 PM 03/03                        
FOWLER                       47 MPH    0240 PM 03/03
3 SSE CLAYTONVILLE           46 MPH    1245 PM 03/03
3 E BOSWELL                  45 MPH    0100 PM 03/03                     
PONTIAC AIRPORT              44 MPH    0115 PM 03/03                        
CHICAGO O'HARE               43 MPH    0212 PM 03/03                        
MILFORD                      42 MPH    1258 PM 03/03 
RENSSELAER AIRPORT           40 MPH    1135 AM 03/03        
WATSEKA                      40 MPH    0100 PM 03/03                        
MONTROSE BEACH LIGHT         40 MPH    0149 PM 03/03 
EAST CHICAGO (CLINE AVE BR.) 39 MPH    0146 PM 03/03                  
2 WNW MICHIGAN CITY (C-MAN)  38 MPH    0520 PM 03/03                        

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURES. NOT ALL DATA LISTED ARE CONSIDERED OFFICIAL.

Forecast Thoughts

Twitter Thread on this Topic

We meteorologists had our hands full forecasting the evolution of this system and applying our expertise. For the local area, there was a fair idea on the event character and what resulting impacts could be, however location was unusually difficult to pin down.

Forecasts have inherent uncertainty that can be conveyed via: • Probability to reach certain snow totals • Showing plausible snow accumulation ranges • Providing the most likely forecast and alternate scenarios • Highlighting areas of high uncertainty

While snow totals get the most interest, we want to stress that that's only one part of a winter event that brings impacts. For instance, on March 3rd, nowhere in our area received 6" of snow, but the 1 to 2" per hour rates were widespread south of I-80 and quickly covered roads, leading to numerous car accidents.

Links

Summaries from Nearby NWS Offices:

• Northern IN (NWS Northern Indiana)
• Southeast MI (NWS Detroit)
• Southern IL and Western KY (NWS Paducah)

Additional Links:

• Winter 2022-2023 Events in Northern Illinois and Northwest Indiana
• National Snowfall Totals
• Snow Depth Information
• Map of Snowfall Local Storm Reports
• Create Your Own Observed Contoured Snowfall Map
• NWS Chicago Science & Past Events Page