March 1-7, 2005
Midwest Weekly Highlights - March 1-7, 2005
Selective Roaring As March Arrives in the Midwest
The month of March 2005 started off with the proverbial roar in the eastern part of the region, as a very strong storm system vacated the Ohio Valley and Great Lakes on the 1st. Much of the precipitation that is accounted for during the first week of March (Figure 1) fell overnight as the month started and into the next day as strong lake effect snows developed. However, the week as a whole was fairly dry, and even the eastern Midwest did not reach normal levels of precipitation except in isolated pockets (Figure 2). Snow fall totals were quite substantial in the Upper Peninsula of Michigan and western Lower Michigan into far southwestern Michigan and northern Indiana (Figure 3), with 3-day totals exceeding a foot in a number of places. Niles, MI, received a total of 17.8 inches of snow during the lake effect event. Temperatures reached record levels in the western Midwest on the 6th, resulting in an anomaly map for the week with above normal temperatures in the western Midwest and below normal temperatures in the eastern Midwest (Figure 4). A 15°F temperature departure gradient existed across the Midwest from western Iowa (+7°F above normal) to eastern Ohio (-8°F below normal). The week ended as it began, with a strong low pressure center and associated cold front moving through the region and causing severe weather in Iowa.
Big Lake Effect Event As Cold Air Streams South
In the aftermath of the deep low pressure center departing the region, a strong push of cold air from Canada traveled over relatively ice free Lake Michigan, setting up an unusually strong and persistent band of heavy snow in southwestern Michigan and northern Indiana (Figure 5, National Weather Service - NWS). After more than a day of persistent snow, precipitation totals passed an inch of liquid water in places (Figure 6, NWS), leading to the aforementioned total of 17.8 inches of snow in Niles, MI, and 15 and 14 inches in nearby Buchanan and Eau Claire, MI, respectively. Even across the border in Granger, IN, 13 inches was observed. A number of places in the Midwest did set records on March 1 for the daily snow fall total, including Marquette NWS office (9.1"), Muskegon (3.4"), and Grand Rapids (2.3"), MI, South Bend (4.0"), IN, and Jackson (1.5"), KY. Mid-winter lows in the negative double digits were common in northern Wisconsin and Minnesota (Figure 7, Unisys), including -33°F at Embarrass, MN. Cold air remained in place for several days in the eastern Midwest; Houghton Lake, MI, tied its record for low temperature on the 4th.
Rumblings of Thunder
A small convective outbreak occurred in western Missouri on the evening of March 3, leading to a linear sequence of severe hail reports (Figure 8, Storm Prediction Center- SPC). The majority of the severe reports were due to one storm progressing slowly south of Kansas City (Figure 9, NWS), dropping hail up to 1.75 inches in diameter. This small thunderstorm complex arrived ahead of a weak low pressure center that crossed the southern Midwest with very little precipitation on the 4th and 5th. A large high pressure area to the south of the Midwest finally moved eastward, allowing a warm return flow from the Gulf of Mexico as far north as central Minnesota on the 6th, where Minneapolis reached 60°F (Figure 10, Unisys). Record maximum temperatures were recorded at Des Moines (74°F), Cedar Rapids (73°F), and Marshalltown (72°F), IA, and Moline (73°F), IL, and there were additional tied records at several more first order stations. But soon the wind picked up as a strong low pressure center whipped a trough of low pressure through the region ahead of a cold front (Figure 11, Unisys). A number of severe hail reports were noted in Iowa (Figure 12, SPC), along with widespread reports of 40-50 mph winds. A small power outage affecting 1,400 customers was reported in Des Moines, IA, but relatively little damage was incurred from the storms as they swept across the Midwest, weakening as they traveled eastward. Cold air returned quickly behind the low, with many locations having their lowest midnight-to-midnight temperature readings on the last hour of March 7. The cold air seemed likely to stay in place for a while as a large upper level trough of low pressure dipped down from Canada to encompass the entire Midwest.