November 21st Snowfall

Low pressure tracked across southern Illinois, and into Indiana on Saturday, November 21.  This system intially spread rain across central and southeast Illinois, but as colder air filtered in from the north, a change over to snow occurred from north to south, overnight and during the morning.  Periods of moderate to heavy snow were observed until the snow tapered off from west to east during the afternoon.  

Blustery northerly winds developed causing some blowing and drifting, mainly north of I-74 where colder temperatures and higher snow amounts were observed.  With soil temperatures in the upper 40s to lower 50s, the snow initially melted in many areas, however snowfall rates were high enough to overcome the melting to allow accumulation to occur, mainly north of a Jacksonville to Paris line.  The highest totals in central Illinois were reported north of a Galesburg to Roanoke line, where 5 to 9 inch totals were received.  

While it was not unusual to see the first snowall in late November, such high totals were quite unusual for a first snow event of the season.  Daily snowfall records were set at many sites, including official climate stations at Springfield (0.5"), Lincoln (1.0"), and Peoria, (4.6").
 

Preliminary Event Snow Totals from NWS Cooperative Observers, SWOP Network, and CoCoRaHS Network

Snow Reports Listed by Amount...

Inches      Location                           County
----------   -----------------------------    -----------------------
 10.0        Altona                               Knox
   8.6        Bradford                           Stark
   7.8        Knoxville                           Knox
   7.5        Abingdon 1N                     Knox
   6.8        Hopewell                           Marshall
   6.4        Sparland 6W                     Marshall
   5.8        Dunlap 2SE                       Peoria
   5.7        Minonk                             Woodford
   5.5        Germantown Hills 2N        Woodford
   5.5        Roanoke                           Woodford
   5.0        Galesburg                         Knox
   5.0        Peoria 5NW                       Peoria
   5.0        Washington 2NE               Tazewell
   4.6        Peoria (official)                  Peoria
   4.0        Mackinaw 1N                     Tazewell
   4.0        Eureka                              Woodford
   3.9        Henry                                Marshall
   3.9        Lacon                                Marshall
   3.6        Morton                             Tazewell
   3.5        Hoopeston                        Vermilion
   3.5        Normal 4NE                       McLean
   3.5        Bloomington 2NE              McLean
   3.2        Sidell 4N                            Vermilion
   3.0        El Paso                              Woodford
   3.0        Homer 2N                         Champaign
   3.0        Danvers                             McLean
   2.9        Ogden                               Champaign
   2.6        Bismark 3W                      Vermilion
   2.1        Pekin                                Tazewell
   2.0        Danville                             Vermilion
   2.0        Tuscola                             Douglas
   2.0        Canton                               Fulton
   1.8        Clinton                              De Witt
   1.1        Mt. Pulaski                         Logan
   1.0        Rushville 4NE                    Schyler
   1.0        Astoria                               Fulton
   1.0        Lincoln NWS                      Logan