As previously reported, based on preliminary data this March in Illinois was 34.1 degrees and the 11th coldest March on record. What were the ten coldest March’s on record? I have listed them in the table below. Also I looked to see what happened in April after these chilly March’s. It turns out that half are above average and half are below average – a virtual coin toss.
The columns labeled “Depart” are the departures from the 1981-2010 statewide averages. Probably the biggest turnaround was between March 1960, which was the coldest March on record and 15.5 degrees below average, compared to April 1960 which was 2.2 degrees above average. The statewide temperature records go back to 1895.
| Rank | Year | March | Depart | April | Depart |
| 1 | 1960 | 25.6 | -15.5 | 54.6 | 2.2 |
| 2 | 1906 | 30.3 | -10.8 | 54.5 | 2.1 |
| 3 | 1912 | 30.4 | -10.7 | 52.6 | 0.2 |
| 4 | 1965 | 31.1 | -10.0 | 52.9 | 0.5 |
| 5 | 1984 | 33.0 | -8.1 | 49.8 | -2.6 |
| 6 | 1932 | 33.2 | -7.9 | 52.1 | -0.3 |
| 7 | 1978 | 33.5 | -7.6 | 52.5 | 0.1 |
| 8 | 1989 | 33.5 | -7.6 | 51.1 | -1.3 |
| 9 | 1947 | 33.8 | -7.3 | 51.0 | -1.4 |
| 10 | 1926 | 34.0 | -7.1 | 45.4 | -7.0 |
| 11 | 2013 | 34.1 | -7.0 | ?? | ?? |
BTW, so far this April has been cool. The first 7 days averaged 44.4 degrees statewide, and about 3 degrees below average.