Winter Storm in Iowa, January 19, 2000

A fast moving low pressure system dropped east-southeast out of the Rockies and into the central U.S. The track of the low went from east central Wyoming, through extreme southern Iowa, then into central Illinois. A large pool of warm air moved north ahead of the low, over the top of a shallow layer of cold air at the surface. Initially, precipitation took the form of mixed freezing rain and sleet. The period of icing was brief however as the airmass was quite dry in the lower levels. Evaporational cooling resulted in a quick transition to snow. During the afternoon, an Arctic cold front sank south across the state. This brought gusty northwest winds and sharply colder temperatures. Snowfall was heaviest over the northeast half of Iowa, generally northeast of a Spencer to Iowa City line. Six inch or greater snows fell in these area. Eight point three inches of snow fell in Mason City, for the highest official total in the County Warning Area. Eight inches was reported in Worth County at Northwood, and also in Cerro Gordo County around the Mason City area. These were among the heavier snowfall totals reported. Most areas received between 6 and 7 inches of snow, with much of it falling in a 3 to 5 hour period. Travel became hazardous quickly as temperatures were in the mid 20s to low 30s during the snowfall. The main problem with the storm was the strong northwest winds as the Arctic cold front moved south across the state in the wake of the low pressure system. Northwest winds of 25 to 35 MPH swept south across the state. Occasional gusts to between 40 and 50 MPH were reported over parts of north central Iowa. The winds caused near blizzard conditions for a two hour period over the northwest Iowa. Blowing snow reduced visibility to near zero in open areas, prompting the Iowa DOT to recommend not travel into northern Iowa for a few hours during the late afternoon. Winds tapered off by early evening and visibilities improved rapidly as the snow stopped.