Winter Storm in Cass, Iowa

A major winter storm affected the entire state during the evening of 31 January into the evening of the 1 February. The northern and southern branch of the jet stream phased over the central U.S. The southern branch drew tropical moisture north into the system as the northern branch brought down colder air. Low pressure organized over the southwest U.S. and moved into Kansas during the evening of the 31st, then tracked across Missouri and into Indiana on the evening of the 1st. Initially, a frontal boundary extended east-northeast out of the low pressure across Iowa. The precipitation fell as rain initially over much of the state. As colder air moved in from the north and west, the rain changed over to heavy wet snow. An extended period of snowfall of a half inch to an inch per hour occurred. Roads became hazardous with some even impassible. Numerous closures occurred. It was fortunate that the storm occurred on a weekend, which decreased the impact somewhat. During the overnight hours, a band of heavy snow set up across central into east central Iowa. These areas received in excess of a foot of snow. This area was generally from west of Des Moines, through Cedar Rapids, into the Quad Cities area. South of the band the snow amounts were generally in the 8 to 10 inch range as the dry slot from the system slowed snowfall rates. North of the band total snowfall was generally around 8 inches. The heavy consistency of the snow during the evening of the 31st into the early morning of the 1st caused power outages as the snow stuck to tree branches. At the peak of the storm, about 16,700 people were without power. As the storm progressed east, winds increased from the north. Winds of 20 to 35 MPH were common, with some gusts of 45 to 50 MPH observed on the 1st. The snow had become drier at that time and was more easily blown around. Blowing snow caused whiteout conditions at times with considerable drifting of the snow. Some of the heaviest snow fell over the central Iowa area. The NWS office in Johnston recorded 14.2 inches, Madrid in Boone County received 14.1 inches, 13.7 inches was reported in Saylorville and Ankeny in Polk County, with 13 inches in Altoona in Polk County. Cold air overspread the state with morning lows on the 2nd falling to zero to 15 below zero. The storm beginning time actually occurred on the 31st of January, though criteria was not met until the 1st of February. The snow started west of an Algona to Fort Dodge to Creston line by 1500 CST on the 31st, reached a Waterloo to Centerville line by 1900 CST on the 31st, and covered the entire CWA by 2100 CST on the 31st. There was one death from the storm. Police in Cass County reported that a woman died of exposure Sunday evening when attempting to get help after crashing her car. A female age 67 lost control and crashed into a ditch around 1630 CST Sunday near Atlantic. She left her car and tried to walk home. Her body was found about four hours later a few blocks from her car. The wind chill was 9 F below zero at the time and she was reportedly not dressed for the weather.