February 22-28, 2010
Midwest Weekly Highlights - February 22-28, 2010
Strong Temperature Gradient This Week
All of the western and southern Midwest were below normal with only parts of Michigan and Wisconsin near or above normal (Figure 1). Temperatures ranged from as much as 20°F below normal along the Iowa-Missouri border to 2 to 3°F above normal in northern Michigan. Daily maximum temperatures were near or below normal across the region with the largest departures in the south (Figure 2) while daily minimum temperatures were near or above normal in the northeast and well below normal in the west (Figure 3). Most of the temperature records during the week were record lows in Iowa and Missouri on the 24th and 25th.
Precipitation
Above normal precipitation extended from northeast Missouri to southern Michigan and northern Ohio. The rest of the region, with the exception of upper Michigan, was below normal during the last week of February (Figure 4). Southern Michigan received more than twice their normal. To the south along the Ohio River, southern Illinois, southern Indiana, and most of Kentucky received less than a quarter of their normal precipitation (Figure 5). Western Kentucky was nearly an inch below normal. The other dry area was the northwest part of the region. The northwest two-thirds of Iowa, the western third of Wisconsin, and nearly all of Minnesota also received less than a quarter of their normal precipitation. Significant parts of northern Iowa and southern Minnesota were dry during the week (Figure 6).
Snowfall during the week was heaviest in Ohio and Michigan (Figure 7). Lake enhanced snow showers dropped over a foot in upper Michigan and in isolated parts of southwest lower Michigan. Late in the week a strong system in the northeast US (Figure 8) was large enough to bring strong northerly winds and snow to Michigan and Ohio. Weekly snow totals for parts of southeast Michigan (Figure 9) and eastern Ohio (Figure 10) were 6-16 inches.
Drought Persists in Upper Midwest
Drought continued in the upper Midwest. Severe drought in northwest Wisconsin is surrounded by moderate drought that extends from east-central Minnesota to western part of upper Michigan (Figure 11). Impacts in this region are long-term and include low stream flows and low lake levels.
Ice Jam in Northern Illinois Breaks Up
After weeks of high water, the ice jam that caused moderate flooding on the Fox River at Dayton, Illinois (LaSalle County) finally broke up this week. Water levels rapidly dropped about 15 feet to well below flood stage. Brief minor flooding occurred elsewhere earlier in the week but, by the end of the week, there were no gauges above flood stage in the nine-state region.
Snow Causes Traffic Fatality and Road Closures
Snow in Ohio and Michigan snarled traffic on the 26th. A fatal accident occurred in the morning as blowing and drifting snow hampered road conditions in Ohio (Darke County). Several other counties in west-central Ohio also declared snow emergencies due to the deteriorated driving conditions. Dozens of accidents kept authorities busy in the area. In southeast Michigan, numerous accidents impacted travel including two which shut down interstate highways for several hours each. In Oakland County, eastbound I-96 was shut down following the jack-knifing of a semi trailer. In St. Clair County, a multi-car accident caused to a long shut down of westbound I-94 to clear the highway.
-MST-