Warmest start to year and spring on record for Midwest
May 2012 ranked as one of the top 10 warmest months for eight of the nine states in the Midwest region with Minnesota being the lone state outside the top 10 (18th) based on preliminary temperature data. May was warmer than normal in all nine Midwest states, continuing the string of above normal months to open the year, according to the Midwestern Regional Climate Center (http://mrcc.isws.illinois.edu) at the Illinois State Water Survey (ISWS).
Although May was not a record-breaking month for the region, it contributed to the record-breaking spring (March through May) and start of the year (January through May) average temperatures in eight of the nine Midwestern states and the region as a whole. Minnesota was the only state not to break its spring and January-May records as 2012 ranked second in both cases. Statewide records dating back to 1895 indicate that nearly half of the spring and January-May records broken in 2012 were from 1921.
Spring temperatures for the Midwest region as a whole, using preliminary May temperatures, surpassed its previous 1977 record of 53.6 degrees with a new record of 55.0 degrees. Preliminary statewide values for spring were 59.3 degrees in Illinois (previous record of 57.3 degrees in 1977), 58.4 degrees in Indiana (56.8 in 1977), 56.1 degrees in Iowa (54.7 in 1977), 61.2 degrees in Kentucky (59.2 in 1921), 48.9 degrees in Michigan (48.0 in 2010), 62.0 degrees in Missouri (59.0 in 1977), 56.3 degrees in Ohio (54.5 in 1991), and 49.8 degrees in Wisconsin (49.3 in 1977). Minnesota fell 0.4 degrees short of the 1977 record of 48.6 degrees.
Start of the year (January-May) average temperatures for the Midwest region finished with a preliminary value of 44.8 degrees, beating the previous record from 1998 by a full 2.0 degrees. At the state level, average temperature values for the January-May period were 48.8 degrees in Illinois (previous record of 47.3 degrees in 1921), 48.4 degrees in Indiana (47.1 in 1921), 44.6 degrees in Iowa (43.5 in 1987), 52.3 degrees in Kentucky (51.3 in 1921), 40.0 degrees in Michigan (39.3 in 1998), 52.1 degrees in Missouri (49.5 in 1921), 47.1 degrees in Ohio (46.5 in 1998), and 39.3 degrees in Wisconsin (38.3 in 1998). Minnesota was 0.4 degrees short of the 1987 record of 37.4 degrees.
The record-breaking spring and January-May average temperatures were not limited to the Midwest. In fact, a majority of the United States east of the Rockies experienced record warmth. The warmest areas stretched from the High Plains into the Midwest.
Spring temperatures were warmest, compared to normal, in eastern Nebraska and western Iowa. The warmest January-May temperatures extended from eastern North Dakota southeastward across northern Iowa.
The warm and relatively dry spring allowed many farmers across the area to get a head start on corn planting compared with 2011. As of the week ending May 20, 2012, the United States Department of Agriculture (USDA) reported that seven of the nine states in the Midwest had planted over 94 percent of their corn acreage with Michigan and Wisconsin having planted 87 percent and 84 percent respectively. All states in the Midwest were ahead of their 2011 and average 2007-2011 planting percentages.
The record-breaking warm spring has not had universal positive effects on agriculture. Fruit trees and vineyards across the Midwest were heavily damaged from freezing temperatures in April. Due to the early and extended period of warm temperatures, many fruit trees began budding in March, four to six weeks earlier than normal, and then were damaged by the April frosts and freezes that occurred across the region.
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).