"After a cold February, the pendulum swung the other way, giving Illinois March temperatures averaging 47.6°F statewide, 6.5°F above normal and the 6th warmest March on record since 1895. Several cities, particularly Champaign-Urbana, set or tied daily high temperature records," says State Climatologist Jim Angel of the Illinois State Water Survey (http://www.sws.uiuc.edu), a division of the Illinois Department of Natural Resources.
March 13 records were exceeded at Chicago (73 degrees), Rockford (74 degrees), and Peoria (78 degrees), and tied at Champaign-Urbana (78 degrees). March 14 records were tied at Springfield (75 degrees) and exceeded at Champaign-Urbana (78 degrees). The March 25 record was exceeded at Champaign-Urbana (80 degrees).
"Statewide March precipitation was 3.43 inches, 0.22 inches above normal, based on preliminary data. Most of the heavier rainfall, 3–6 inches, fell over the northern half of the state. The southern half of the state was drier, with rainfall totals of 1–3 inches in most areas," adds Angel.
National Weather Service outlooks for April–June and July–September call for both temperatures and precipitation having equal chances of being above, below, or near normal.
"Those very warm March temperatures may have fooled us, and plants, into thinking spring was here to stay, but wintry temperatures returned in early April. April is usually when the last freezing temperatures occur: northern Illinois (April 28), central Illinois (April 14–21), and southern Illinois (April 7). If you're thinking of planting tender annuals, add about 2 weeks to those dates. See (http://www.sws.uiuc.edu/atmos/statecli/Frost/frost.htm) for more frost information," concludes Angel.
Disclaimer: Data used for all statistics provided herein are from the Midwestern Regional Climate Center and are based on preliminary data.