February 2008
Midwest Overview - February 2008
Cold and Snowy
February was a cold and very wet month across most of the Midwest, and much of the northern and northeastern portions of the region was buried in snow.
Average daily temperatures ranged from 8°F to 9°F below normal in central and eastern Iowa and in northwestern Minnesota, to 1°F above normal in extreme southeastern Kentucky (Figure 1). The colder than normal weather in the northern Midwest was aided by a persistent snow cover as storm after storm brought snow and ice to the region. Temperatures the first week of the month were above normal across the region, ranging from 0°F to 3°F above normal from western Minnesota south through western Kansas while temperatures were 10°F to 12°F above normal in the Ohio Valley (Figure 2). After the first week of February, a series of Arctic outbreaks kept temperatures generally below normal north of the Ohio River. The northern half of the Midwest experienced some of the coldest weather of the season on February 20 when temperatures plunged to -33°F in northwestern Minnesota, and lows between -10°F and -25°F occurred across the remainder of Minnesota, Iowa, and Wisconsin.
Precipitation was much above normal for much of the Midwest in February, typically the driest month of the year. Precipitation was 200 percent of normal or more in a wide band extending from southwestern Missouri through Lower Michigan (Figure 3). Drier than normal conditions occurred in the northwestern quarter of the region, including most of Minnesota and northwestern Wisconsin where precipitation was only 25 to 75 percent of normal precipitation. Near to slightly below normal precipitation occurred in southeastern Kentucky as well. There was little change in the U.S. Drought Monitor throughout the month, with small areas of drought persisting in northwestern Minnesota and southeastern Kentucky.
Record-setting Snow
Snowfall was much above normal across a significant portion of the Midwest north of the Ohio River. Snowfall was four to six times normal from eastern Iowa to eastern Wisconsin (Figure 4). Seasonal snowfall totals at many locations from northern Illinois through southern Wisconsin are already more than twice normal and in the top ten snowiest. At the end of February Madison, WI had accumulated 89.8 inches of snow, smashing the previous seasonal snowfall record of 76.1 inches of snow in the winter of 1977-1978. Rockford, IL had accumulated 66.1 inches of snow by the end of February, making this the second snowiest season so far. The 65.1 inches of snow Rockford received December 1-February 29 was a new record for the winter (December, January, February), eclipsing the old record of 63.4 inches set in 1978-1979. So far this is the 18th snowiest season in Chicago, with 50.9 inches of snow measured at Chicago O'Hare. At the end of February 4 or more inches of snow blanketed the northern two-thirds of the region (Figure 5).
Fog to Floods and Everything In Between
The Midwest experienced all manner of severe weather during the month of February, from severe thunderstorms to heavy snow. An unusual event the first week of the month was a very dense fog with horizontal visibilities of less than 1/4 mile over a wide area of the central Midwest, extending from eastern Iowa through central and northern Illinois to northern Indiana and southern Michigan. The dense fog developed overnight February 3-4, with visibilities generally less than 1/4 mile, and conditions deteriorated during the day. This event was unusual in that the very dense fog occurred during the afternoon and early evening hours and persisted in many locations for more than 6 hours. The fog brought air travel to a standstill and driving conditions were extremely hazardous. There were numerous traffic accidents throughout the Midwest as a result of the fog, a few with fatalities.
A severe weather outbreak in the Ohio Valley on February resulted in 24 tornadoes reported in Kentucky out of 131 for the entire outbreak. Damaging winds were reported from southern Illinois through southern Ohio. A brief period of mild weather and heavy rain on top of snow on the ground resulted in widespread flooding across large portions of the Midwest the first week of the month. On February 7 moderate to major flooding was being reported on rivers in Indiana, Illinois, Missouri, and Ohio.
Areas from the Ozarks in Missouri through the Ohio Valley were affected by storms the second and third weeks of February. Freezing rain coated the southern Midwest with ice, then topped it off with sleet and snow. Meanwhile, the north central Midwest from Iowa through northern Illinois, southern Wisconsin, northern Indiana, and southern Michigan continued to see snow pile up as a series of storms made their way through the Midwest.
Winter Season Cold, Wet
Most of the nine-state Midwest region experienced a colder than normal winter (December, January, February). The exceptions were Michigan, Ohio and Kentucky, which were near to slightly above normal (Figure 6). North and west of the Ohio River, temperatures ranged from near normal along the Ohio River to 4°F to 5°F below normal across most of Iowa and the southwestern half of Minnesota. Precipitation was near to well above normal with the exception of Minnesota, where precipitation was only half or normal for the three-month period in the southwestern part of the state and 50 to 75 percent of normal elsewhere (Figure 7). Precipitation was also slightly below normal in far southeastern Kentucky. Snowfall was twice normal in a band from northwestern Missouri east-northeastward into southern Lower Michigan (Figure 8).
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