Vince_Condella's Blog

November 11 is an infamous day in weather history.  The Armistice Day storm of 1940 killed 154 people, most of them hunters in the Midwest who were out enjoying a fine late autumn day.

The western Great Lakes experienced temperatures in the 50s and 60s with a mild south wind.  But while it was in the mid 50s in Chicago, Sioux City, Iowa had a temperature of 12 degrees with a raging north wind.  Strong low-pressure over central Iowa deepened quickly during the overnight hours, strengthening to that of a minimal hurricane by midday on the 11th.

The primary Midwest weather forecast back in 1940 originated from the Weather Bureau office in Chicago.  This office was not manned 24 hours per day, and it was during the overnight hours when the storm became so powerful.

The result was an afternoon of sharply falling temperatures, howling wind, and blizzard conditions.  The low-pressure center had a central pressure of 28.66" over Duluth by the evening hours, with western Wisconsin, Minnesota, and Iowa bearing the brunt of the snow and wind.  Snowfall of up to 27 inches was not uncommon.  Winds gusted over 50 miles per hour, and snowdrifts piled as high as 20 feet.

Many duck hunters were out along the Mississippi River enjoying a warm day when the storm came upon them.  Some escaped to islands on the river, but 5-foot waves and 50 mile per hour winds flooding their campgrounds.  Many froze to death.  Sixty-six sailors died on Lake Michigan when 3 freighters sank.  Thirteen died in Wisconsin and Illinois, 4 in Michigan, and 49 in Minnesota.

After this disaster, the Weather Bureau expanded the number of forecast offices in the Midwest and required 24-hour staffing.  This major storm in 1940 ranks as one of the greatest natural disasters to strike the Midwest.