Midwest Overview - December, 2004

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December Features Record-Breaking Snow, Cold, and Warmth

It was a climatological roller coaster ride this December in the Midwest.  The month started out rather mild across most of the region.  A major storm just prior to Christmas dumped record amounts of snow, in excess of two feet in some locations, on the Ohio Valley.  Following the storm, arctic air spread across the eastern half of the country,  and resulted in a cold Christmas with some record low temperatures over the snow-covered portions of the southern Midwest and a bone-chilling reading of -42F in Embarass, MN on December 23.  As the end of the year approached,  strong southwest winds pulled much warmer air back into the Midwest, with temperatures reaching the 60s as far north as southern Michigan.  Record highs were set or tied at a number of locations on December 30 and 31. When all was said and done, December temperatures ranged from near normal to 2F below in the eastern portions of the region, to 4F to 6F above normal in southwestern and western Minnesota (Figure 1).  

December precipitation was well above normal in a broad arc extending from northern Minnesota across northern Michigan, then south through Ohio and back westward through Kentucky (Figure 2).  Precipitation was 100 to 220 percent of normal in this area, with most of it coming as snow.   The driest portion of the region extended from southwestern Minnesota south through northwestern Missouri, where less than 0.50 inches of precipitation was recorded (Figure 3).

Mild weather early in December precluded much in the way of snow. Snowfall was well below normal across the western half of the region. However, the week prior to Christmas more than made up for it in the Ohio Valley and across the northern Midwest (Figure 4).  In the Ohio Valley, the storm of December 21-23 piled almost 30 inches of snow on south central Indiana, and more than 2 feet from south central Indiana into southwestern Ohio.  Many locations set new 24-hour snowfall records, and this storm alone also made this the snowiest December on record for locations such as Paducah, KY and Evansville, IN.  The storm stranded holiday travelers, caused power outages, and caused damage to many structures, mostly from collapsed roofs.  Freezing rain on the southern edge of the storm in Ohio caused extensive icing of trees and power lines.  Power was still out for 10,000 Ohio  residences on December 26.  Freezing rain also caused travel problems across the northern half of Minnesota at the end of the month.