May 23-31, 2001:

The final period of the month, May 23 to May 31, was certainly moist in the northern and eastern parts of the region, and cold throughout the region, but did not have the heavy rain of previous weeks. A strong upper level low parked over the northern Illinois/southern Wisconsin/Great Lakes region (Figure 21), and a number of upper air disturbances, weak and strong, spiraled around the low like a pin wheel (Figure 22). Precipitation totals were generally less than two inches in the Midwest, but in many states it rained nearly daily until the last 3 days of the month (Figure 23). Many days started with some sun, followed by instability cloudiness and then organized precipitation. The wet areas received up to an inch more rain than normal in the northeastern half of the Midwest (Figure 24). Temperatures were 6-10°F below normal in the core of the Midwest (Figure 25). Snow was observed in Minnesota on May 22, and in Iowa on May 23. On the 23rd, Jackson, KY, set a record low temperature for the day, and a large number of places set a record low high temperature for the day, including: Moline, Dubuque, and Des Moines, IA; La Crosse and Eau Claire, WI, and Rochester and Minneapolis/St. Paul, MN. The month end with very dreary conditions, cold and cloudy.