Midwest Overview - February 2012

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Above Average Precipitation in Dry Areas

For the month of February, precipitation totals around the Midwest ranged from only 0.3 inches to over 3 inches in some places. The lowest precipitation totals for the month are found in northern Minnesota and northern Michigan. The highest precipitation totals of 3 inches or greater are found in central Missouri and southeast Kentucky (Figure 1). There were several daily precipitation records set during the month and some monthly precipitation records.

The 1.5 inches to 3 inches in southern Minnesota and northwest Iowa resulted in monthly precipitation that was 2 to 4 times their normal February precipitation (Figure 2). Above average precipitation in this region has been fairly rare the last few months. In fact, February is the first month since July that some places in Minnesota are experiencing above average monthly precipitation. This region has been on the US Drought Monitor since September and during the month of February, there was not much improvement for the Minnesota and Iowa region (Figure 3). However, with most of the precipitation this month falling during the last week, there may be some improvement on next week's release of the US Drought Monitor.


Snowfall Near Normal across Midwest

A majority of the Midwest received near normal snowfall (within 2.5 inches) during the month of February. Portions of the upper Midwest experienced above average snowfall, while others experienced below normal snowfall (Figure 4). The greatest departures of 5 inches to 10 inches above normal February snowfall were in northern Wisconsin, northern Minnesota, and northeast Michigan. The greatest negative departures from normal snowfall are in the Upper Peninsula of Michigan. This region experienced departures on the order of 10 inches to 20 inches below normal.

Total accumulated snowfall around the Midwest ranged from the southwest corner of Kentucky receiving no snowfall to northern Wisconsin and the western portions of the Upper Peninsula receiving 20 inches to 30 inches of snowfall (Figure 5). A few snow events during the month resulted in several daily snowfall records being set during February, and a few monthly snowfall records were even broken. More details on February snow events can be found in the Weekly Highlights.


Unseasonably Warm February Temperatures

Average temperatures in February ranged from 40°F to 45°F in the southern Midwest to 15°F to 20°F in northern Minnesota (Figure 6), resulting in temperatures that were above average for a majority of the region (Figure 7). The highest departures of 7°F to 9°F above normal were found in the upper Midwest in Minnesota, Michigan, and Wisconsin. Minimum temperatures in this same region were 9°F to 11°F above normal (Figure 8). There were over 450 daily high temperature records set during the month.

The second week of February was the only week where a majority of the Midwest experienced near to below normal temperatures.


Leap Day Severe Weather Outbreak

The first major severe weather outbreak of 2012 started in the early morning hours of Leap Day. The strong low-pressure system that produced this severe weather moved through the Midwest on February 29th, prompting severe weather warnings for the lower Midwest and winter storm warnings for the upper Midwest.

The severe weather outbreak in the lower Midwest resulted in 20 tornado reports, 46 hail reports, and 112 high wind reports. The impact of the severe weather was especially felt in Harrisburg, Illinois when an EF-4 tornado went through the town, creating widespread damage and 6 fatalities. More details on the Leap Day severe weather outbreak and the concurrent winter storm in the upper Midwest can be found on the February 22-29 Weekly Highlights.


Winter Season Summary

The end of February marked the close of the meteorological winter season of December, January, and February. Overall, the Midwest experienced unseasonably warm average temperatures and below normal snowfall this winter. Average temperatures were at least 4°F above normal across the Midwest, with parts of Minnesota experiencing average temperatures that were 7°F to 9°F above normal (Figure 9).

Total accumulated snowfall during the winter ranged from only 0.1 inches in the south to just over 100 inches of snow in Upper Michigan (Figure 10). This winter, the only regions with above average snowfall in the Midwest were northern Wisconsin and parts of northern Minnesota and northern Michigan. The rest of the region received near to below normal snowfall (Figure 11).

This winter, southern parts of the Midwest received 10 inches to 15 inches of precipitation, while parts of northern Minnesota only received half of an inch to one and a half inches of precipitation (Figure 12). Northern Minnesota received about half of its normal winter precipitation, while southern Minnesota and western Iowa received 125% to 175% of their normal winter precipitation (Figure 13).

-MW-