Midwest Weekly Highlights - March 8-14, 2005

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Dry and Cold Week in the Midwest

Storms during the period of March 8-14 largely bypassed the Midwest, with only one substantial clipper cutting through the region during the week. Less than 0.5 inches of precipitation fell over the region, except for some portions of the Ohio Valley and Kentucky (Figure 1). More than half of the Midwest received less than 50% of normal precipitation, while a large potion of Illinois, Iowa and Missouri recorded less than 25% of normal (Figure 2). Less than 5% of the Midwest received above normal precipitation amounts. The clipper system in the middle of the period did bring 3-6 inches of snow from northeastern Minnesota to eastern Ohio, and a few of the lake effect snow belts received 6-10 inches (Figure 3). The air imported from Canada was cold as well as dry, with the northern and eastern portions of the region averaging 10-14°F below normal for the week, and even the warmest part the southwestern Midwest ending the week a few degrees below normal (Figure 4). Much of Michigan, including Grand Rapids and Muskegon, stayed below freezing for the entire week. Marquette, MI, set a new record low temperature of -15°F on the 13th, and Gaylord and Muskegon, MI, set new record low temperatures on the 14th of -8°F and 5°F, respectively. Only on the 12th did some warm air enter Missouri, tying a record high of 82°F in Joplin, MO, but cold air quickly returned as the large eastern North American trough (Figure 5, Climate Diagnostics Center) dominated the region during the week.

Clipper Slices Through Northeastern Midwest

The largest impact of a weather event during the period actually occurred in a heavy lake effect band that hit the Grand Rapids, MI, area on the 8th. Snow reduced visibility to near zero, and a total of 84 vehicles crashed along a 1.5 mile stretch of highway. One person was killed, and 33 were injured. The most widespread snow event occurred on March 10-12, producing a snowfall total pattern very similar to that for the week (Figure 6). A strengthening low pressure center entered Minnesota on the 10th (Figure 7, College of DuPage), swinging a trough southward through the central Midwest. Snow formed ahead of the surface trough (Figure 8, University Corporation for Atmospheric Research), and brought 3-6 inches of snow along its path. Further lake effect snow fell in the northern UP of Michigan, southwestern Michigan, and northeastern Ohio. Muskegon and Marquette, MI, set new daily snowfall records for March 11 of 4.9 and 4.8 inches, respectively. The week ended with a stationary boundary forming just south of the Midwest, providing some uplift to form very light snow showers in the southern Midwest on the 13th and 14th.