In the month of September, there have been at least nine years in which snow has been recorded in Iowa, most recently in 1995. (a few flakes fell across Northern Iowa on 9/22/95)

But on September 16, 1881, between 4-6" of snow fell in Western Iowa in Pottawattamie County.

According to the National Weather Service in Des Moines, this is one of just two occasions where measurable snow has fallen in Iowa in the month of September. The other was on September 25, 1942 (4” in Mason city and Forest City)

Other dates featuring 'September Snow' in Iowa, according to the National Weather Service in Des Moines:

1881 – widespread measurable snowfall on the 16th (see above)
1895 – “first snowflakes” noted at Madrid on the 28th
1912 – “few flakes” observed at Storm Lake and Marshalltown on the 17th and 18th
1938 – flurries reported at Orleans and Maquoketa on the 18th and 19th
1939 – traces of light snow and sleet across northern IA, 0.1” at Sheldon and 0.2” at Sibley, on the 29th and 30th
1942 – widespread measurable snowfall on the 25th (see above)
1961 – light snow across northwestern half of IA on the 30th, a few measurable amounts ranging up to 3.0” at Swea City
1985 – a few flakes at Des Moines on the 24th, widespread wintry mix with 0.5” at Audubon and Storm Lake on the 29th and 30th
1995 – a few flakes and ice pellets mixed with rain across northern IA on the 22nd

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