Sioux City Snowstorm: Iowa Time Machine October 9, 1970

Iowa Time Machine ⏰: On October 9, 1970, Sioux City picked up 5.1 inches of snow in a historic early-season blizzard. The National Weather Service identifies the event as Sioux City’s earliest significant snowfall, while Iowa State University Extension describes it as the city’s earliest recorded accumulation of at least one inch.

Early snow isn’t always an anomaly in Iowa. Sioux City had experienced snow before October: the National Weather Service records 0.4 inches on September 30, 1961. A measurable snowfall and a substantial accumulation are separate categories, and the October storm crossed decisively into the latter.

Sioux City wasn’t alone. Storm accounts reported three inches at Shenandoah, four inches at Logan and Rock Rapids, and 4.5 inches at Sheldon. Across western Iowa, the storm delivered an unmistakable preview of winter.

More than half a century later, the storm remains a reference point for discussing how early substantial snow can arrive. An Iowa State University Extension weather update revisited it on October 9, 2025, noting that the 5.1 inches was Sioux City’s earliest accumulation of one inch or more and its third-highest October snowfall on record. #Iowa #OTD #History #Weather #Snow