A prolonged period of well below normal and at times record temperatures and light snowfall events culminated in a classic winter storm on Presidents Day that brought up to 10-12 inches of snow to the county warning area. An anomalously cold Arctic air mass had engulfed the region for a week prior to this event, keeping temperatures below freezing. A renewed shot of Arctic air surged into the area over the weekend, and temperatures struggled to make it out of the single digits Sunday and Monday, with lows dropping below zero. Deep atmospheric lift provided by coupled upper-level jet streaks, an approaching mid-level trough, and mid-level frontogenesis took advantage of modest Gulf moisture moving north into the mid-Mississippi Valley to produce snow, heavy at times, Monday the 15th of February. The highest snowfall amounts occurred in east-central and southeast Missouri and southern Illinois where stout lift and the highest moisture resided.

Heavy Snow in FAYETTE, ILLINOIS
From 14-FEB-21 20:00:00 to 15-FEB-21 22:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Fayette County by 10 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches.

Heavy Snow in CALHOUN, ILLINOIS
From 14-FEB-21 22:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Calhoun County by 8 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches, especially across the southern half of the county.

Heavy Snow in MACOUPIN, ILLINOIS
From 14-FEB-21 22:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Macoupin County by 9 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches, especially across the southern half of the county.

Heavy Snow in RANDOLPH, ILLINOIS
From 14-FEB-21 18:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Randolph County by 8 pm on February 15th. Red Bud reported 11.7 of snow.  Overall, snowfall amounts ranged from 6 to 12 inches.

Heavy Snow in MONROE, ILLINOIS
From 14-FEB-21 18:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Monroe County by 8 pm on February 15th.  Waterloo reported 9 inches of snow.  Overall, snowfall amounts ranged from 6 to 9 inches.

Heavy Snow in ST. CLAIR, ILLINOIS
From 14-FEB-21 19:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited St. Clair County by 8 pm on February 15th.  Nine and a half inches of snow was reported in Shiloh and 3 miles north of Freeburg.  Overall, snowfall amounts ranged from 6 to 10 inches.

Heavy Snow in WASHINGTON, ILLINOIS
From 14-FEB-21 19:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Washington County by 9 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches.

Heavy Snow in CLINTON, ILLINOIS
From 14-FEB-21 19:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Clinton County by 9 pm on February 15th.  Nine inches of snow was reported in St. Rose.  Overall, snowfall amounts ranged from 6 to 9 inches.

Heavy Snow in MARION, ILLINOIS
From 14-FEB-21 19:00:00 to 15-FEB-21 22:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Marion County by 10 pm on February 15th.  Kell reported 11.9 inches of snow.  Overall, snowfall amounts ranged from 8 to 12 inches.

Heavy Snow in MADISON, ILLINOIS
From 14-FEB-21 20:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Madison County by 9 pm on February 15th.  Three miles east of Highland reported 9.4 inches of snow. Overall, snowfall amounts ranged from 6 to 10 inches.

Heavy Snow in BOND, ILLINOIS
From 14-FEB-21 20:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Bond County by 9 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches.

Heavy Snow in GREENE, ILLINOIS
From 14-FEB-21 22:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Greene County by 8 pm on February 15th.  Overall, snowfall amounts ranged from 4 to 6 inches, especially across the southern half of the county.

Heavy Snow in JERSEY, ILLINOIS
From 14-FEB-21 21:00:00 to 15-FEB-21 20:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Jersey County by 8 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches.

Heavy Snow in MONTGOMERY, ILLINOIS
From 14-FEB-21 22:00:00 to 15-FEB-21 21:00:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Several rounds of snow beginning the evening of February 14th. The last round of accumulating snow exited Montgomery County by 9 pm on February 15th.  Overall, snowfall amounts ranged from 6 to 8 inches, especially across the southern half of the county.