Warm North, Cold South
Temperatures were warmer than normal across the northern Midwest while the Ohio River Valley was cooler than normal during the first week of December
(Figure 1). Some areas of northwestern Minnesota were more than 10°F above normal, while most of Iowa, Wisconsin and northern Michigan were 1-4°F above normal. Near-normal conditions were observed across most of Missouri, central Illinois and southern Lower Michigan as temperatures transitioned cooler across the Ohio River Valley. Most of Kentucky was 4-5°F below normal.
With high pressure dominating during the period, very little precipitation fell across the Midwest (Figure 2). Iowa and Minnesota and nearly all of Wisconsin received no precipitation, while most of Indiana and Michigan had less than a tenth of an inch. Only a few areas in Ohio, Kentucky and extreme western Missouri received more than half an inch.
Heavy lake-effect snowfall was observed in northeaster Ohio, however
(Figure 3). Locally heavy totals through the mornings of December 1 (Figure 4) and December 2
(Figure 5) were over a foot in many cases, with a report of 24.8 inches in Chardon (Geauga County). These heavy totals led to more than twice the normal amount of liquid precipitationin these areas (Figure 6). This was the only area in the region with significantly wetter than normal conditions.
Abnormally Dry Conditions Expand in Minnesota
While drought coverage in the Midwest remained steady, a significant increase in abnormally dry conditions was observed in Minnesota as of the December 1 U.S. Drought Monitor
(Figure 7). Abnormally dry conditions increased by more than 30 percent in the state, while drought coverage also increased by more than 2 percent. Little change was observed elsewhere, with western Iowa remaining in drought along with parts of northern Missouri, central Illinois and northwestern Indiana.