Midwest Overview - December 1-7, 2002

The weather during the first week of December was quite active in the southern tier of the Midwest and in the Great Lakes snow belts. A major winter storm traveling along the southern boundary of the Midwest dropped about 0.5 to 1.5 inches of water equivalent precipitation, much of it in the form of snow and/or freezing rain (Figure 1). The snow belt regions south and east of the Great Lakes also received about an inch of water equivalent. However, the vast majority of the Midwest was well below 50% of normal precipitation for the week (Figure 1a), continuing the drying trend evident recently. Lake effect snow was most problematic on the 3rd, when more than 5 inches fell in Chicago and disrupted air transportation. Some locations along the southern storm track received up to 10 inches of snow (Figure 2), while broad areas in the central Midwest have not yet received their first inch of snow. Temperatures were far below normal throughout the Midwest during the December 1-7 period, ranging from 2°F below normal in the central-west Midwest to up to 14°F below normal in the central-east Midwest (Figure 3). Lansing, Michigan, shattered all time records for the 3rd by 10°F with a minimum temperature reading of -18°F on that date. In Detroit, which tied its record of 3°F, two men who had spent the night outside were found frozen to death. Finally, the areas of the central Midwest that have received very little precipitation in six weeks continued to dry, both on the surface and through percolation of water downward out of the soil that is not being replaced by new precipitation or snow melt. The U.S. Drought Monitor shows a new area of moderate drought in northern Illinois (Figure 4, National Drought Mitigation Center).

The large ice and snow storm on December 3-5 was forecasted to be a troublemaker (Figure 5, Storm Prediction Center), and proved to be that and more. More than 1.5 million people lost power nationwide due to the storm, and dozens of deaths were recorded from Oklahoma to New England due to slippery roads and falling trees. In the Midwest, moderate to heavy precipitation occurred in southern Missouri, southern Illinois, and Kentucky (Figure 6, UIUC Dep of Atmospheric Science) when cold air was already in place (Figure 7, UIUC DAS). In Missouri, at least 4 people died in weather related road accidents, while 6 died in icy collisions in Kentucky. Hundreds of automobile accidents were reported in the St Louis area alone, as the ice and snow arrived just before morning rush hour and many of the roads had not been treated. Thousands lost power in Kentucky as power lines were snapped by ice-weighted tree limbs. Eastern Kentucky received up to 8 inches of snow (Figure 8, NWS) and 0.5 inches of ice (Figure 9, NWS). Despite these losses, the Midwest dodged a bullet compared to the massive power outages experienced in the Carolinas and heavy snows that fell along the East Coast.