March was the warmest on record for the nine-state Midwest region, based on preliminary temperature data. The average temperature for the region was 50.3 degrees Fahrenheit, which breaks the previous record of 46.9 degrees set over 100 years ago in 1910, according to the Midwestern Regional Climate Center (http://mrcc.isws.illinois.edu) at the Illinois State Water Survey (ISWS).
Each of the nine Midwest states also set statewide records for the warmest March. Statewide records go back to 1895, and the existing records were all from the early to mid-20th century. Preliminary statewide average temperatures for March are 54.9 degrees in Illinois (previous record 1946), 54.4 degrees in Indiana (1946), 51.3 degrees in Iowa (1910), 57.6 degrees in Kentucky (1945), 44.5 degrees in Michigan (1945), 42 degrees in Minnesota (1910), 57.7 degrees in Missouri (1910), 51.5 degrees in Ohio (1946), and 45.3 degrees in Wisconsin (1910).
Throughout the month, over 6,400 daily record high temperatures (including both minimum and maximum temperature) were set or tied, with over 650 of them also setting records for the warmest temperature for any day in March. A majority of the records were set during the middle of the month, from the 14th through the 24th of March, when hundreds of records fell each day.
March average temperatures ranged from 10 degrees above average in Kentucky to 17 degrees above average in northwest Iowa, southern Minnesota, and western Wisconsin. During the record-breaking period from March 14 to 24, temperature departures ranged from at least 13 degrees above average in southwest Missouri to just over 29 degrees above average in central Wisconsin and northern Michigan.
Cities across the Midwest experienced their warmest March on record. In St. Louis, Missouri, the average March temperature of 61.1 degrees was 14.8 degrees above normal, which broke the previous warmest March record of 57.5 degrees (set in 1910). Cincinnati, Ohio experienced an average March temperature of 55.3 degrees, which was 11.7 degrees above normal, breaking the previous warmest March record of 54.7 degrees set in 1946.
Further to the north, Minneapolis, Minnesota and Detroit, Michigan were two of several cities in the upper Midwest region to experience their warmest March on record. With an average March temperature of 48.3 degrees, Minneapolis broke the previous warmest March record by 3.4 degrees (set in 1910). Detroit experienced an average March temperature of 50.7 degrees, which was 13.5 degrees above normal, breaking the previous record of 47.9 degrees set in 1945.
For more local information on records broken in March 2012, visit the custom Google map produced by the Midwestern Regional Climate Center and click on the pins to find a link to your local National Weather Service report (http://g.co/maps/mshqb). The Earth System Research Laboratory (ESRL), a program of the National Oceanic and Atmospheric Administration, has produced a draft report on why this historic March heat wave occurred: http://www.esrl.noaa.gov/psd/csi/events/2012/marchheatwave/index.html.
The Midwestern Regional Climate Center is a cooperative program of the Illinois State Water Survey and the National Climatic Data Center (National Oceanic and Atmospheric Administration, U.S, Department of Commerce).
