January 24-31, 2001:

A shift in the jet stream set a large trough to the west of the Midwest during the last week of January, bringing both warmer weather and a large rain producing system to the region. Temperatures this week were 4-6°F above normal in most of the Midwest, with even larger warm departures in the northern tier (Figure 15). More importantly, precipitation amounts exceeded 300% in a large potion of the Midwest, including southern Minnesota, Iowa, most of Missouri, and northern Illinois (Figure 16). These areas were just beginning to get quite dry, but the heavy rains received during the week helped restore topsoil moisture levels considerably. Even though the week was warmer than normal, the first few days of the period were cool enough for the Midwest to receive a widespread snowfall. Some areas of western Iowa and southwestern Minnesota also received additional snow during the passage of the big rain-producing low later in the period (Figure 17). Both major systems of the week were accompanied by severe human impacts, unfortunately.