Average Temperature

Temperatures were below normal to the east and above normal to the west (Figure 1). Across Missouri, western Iowa, and southwestern Minnesota, temperatures averaged up to 5°F above normal. Across much of the rest of the region, temperatures were near to slightly below normal by 1-4°F.

Minimum temperatures were below normal for the entire region (Figure 2). Minimum temperatures were most below normal across Minnesota’s Arrowhead region, eastern Indiana, and much of Ohio. In those locations, they were over 10°F below normal for the week. Most of the region was 5-10°F below normal. Record low temperatures started the week in places like Terre Haute, where minimum temperatures bottomed out at or below -10°F for two consecutive days, December 14-15, which has only happened twice before in December since records began in 1875.

Meanwhile, maximum temperatures were mostly above normal (Figure 3). Areas west of the Mississippi River were nearly 10°F above normal for the week, and some spots, like Kansas City, Missouri, were over 10°F above normal for the week. Much of the rest of the region was slightly above normal, save Ohio and parts of Michigan, which were near normal. In International Falls, Minnesota, the mercury hit 50°F on December 16, which was only the 6th time temperatures rose to 50°F in December since records began there in 1895.

Precipitation & Drought

Precipitation was generally below normal (Figure 4). Many places received less than 50 percent of normal precipitation, particularly along and west of the Mississippi River. Only in some of Minnesota’s northernmost locations and central Kentucky through Central Ohio was precipitation near normal. While much of the precipitation this week fell as rain, it fell as snow across the Upper Midwest. Michigan’s Upper Peninsula (UP) observed nearly one foot of snow this week (Figure 5).

Drought remained largely unchanged over the prior week. There were minor expansions of D0 conditions (abnormally dry) across the region (Figure 6). Other categories remained largely unchanged.