December 20-31, 2000:

A series of "Alberta Clipper" storm systems brought more snow and reinforced the very cold weather throughout the Midwest during the December 20-26 week. The cold weather, snow, and strong winds behind each of the small storm systems continued to disrupt holiday travel. Amtrak's City of New Orleans train from Chicago to New Orleans was running almost a half-day late on December 22 mainly because of mechanical problems brought on by the cold weather. The cold weather helped maintain an extensive snow cover in the Midwest. One to two inches of snow is on the ground as far south as the Ohio River. Only in Kentucky is the snow cover spotty. The fast moving storms of the past seven days brought significant snow fall totals to parts of Iowa, Wisconsin, and Michigan, with lighter snows further south (Figure 10). An upper level low pressure system moving slowly through the Southern Plains spread light snow as far north as central Illinois on December 26. Amounts ranged from two to three inches in the southern half of Missouri to an inch or less in Illinois and Indiana. This was the same storm system that brought severe icing to parts of Texas and Arkansas.

The last few days of the millennium passed rather coldly and quietly in the Midwest, with only one significant storm passage between December 27 and 31. Despite low liquid water equivalents in the precipitation totals on December 28 and 29, almost all the precipitation came in the form of snow. Minneapolis, Milwaukee, and Chicago were significantly impacted by up to a foot of snow (Figure 11). The main snow event occurred as a low pressure "clipper system" moved through the area from northwest Minnesota to central Illinois, and then eastward across to the east coast (where it contributed to the formation of a major nor'easter). The Chicago area also suffered from some persistent lake effect snows on the 30th as the low moved eastward and brought a northeast flow in from Lake Michigan. Air traffic was strongly impacted in Minneapolis and Chicago by snow, while St. Louis air travelers suffered delays caused by moderate freezing rain conditions caused by some overrunning warm air. This event completed snow fall totals for December, with at least 15 first-order stations reporting their greatest December or greatest one-month snow fall totals ever observed. The new year has not revealed a warming tendency yet, but some warming is expected later in the first week of January, especially in the western Midwest.