The Armistice Day Blizzard (or the Armistice Day Storm) took place in the Midwest region of the United States on November 11 (Armistice Day) and November 12, 1940. The intense early-season "panhandle hook" winter storm cut a 1,000-mile-wide (1600 km) swath through the middle of the country from Kansas to Michigan.

Meteorological synopsis

On November 7, 1940, the low pressure system that later developed into the storm was affecting the Pacific Northwest and produced the 40 mph winds that destroyed the Tacoma Narrows Bridge. On November 10 the fast-moving storm crossed the Rocky Mountains in just two hours on its way to the Midwest. The morning of November 11, 1940, brought with it unseasonably high temperatures in the Upper Midwest. By early afternoon, temperatures approached 65 F over most of the affected region. However, as the day wore on conditions quickly deteriorated. Severe weather was reported across much of the Midwest with heavy rain and snow, a tornado, and gale-force winds were all reported. Temperatures dropped sharply, winds picked up and rain, followed by sleet and then snow, began to fall. An intense low pressure system tracked from the southern plains northeastward into western Wisconsin, pulling Gulf of Mexico moisture up from the South and pulling down a cold arctic air mass from the North. The result was a raging blizzard that would last into the next day. Snowfalls of up to 27 in, winds of 50 to 80 mph, 20 ft snow drifts, and 50 F-change temperature drops were common over parts of the states of Nebraska, South Dakota, Iowa, Minnesota, Wisconsin, and Michigan. In Minnesota, 27 in of snow fell at Collegeville, and the Twin Cities recorded 16 in. Record low pressures were recorded in La Crosse, Wisconsin, and Duluth, Minnesota. Transportation and communications were crippled, which made finding the dead and injured more difficult. The Armistice Day Blizzard ranks #2 in Minnesota's list of the top five weather events of the 20th century. Survivors describe the cold as so severe that it was difficult to breathe, with the air so moisture laden it was thick like syrup and that the cold seared the survivors lungs like a red-hot blade. Many individuals claim that animals were aware of the upcoming weather shifts which led to animals moving rapidly from the area. Duck hunters who were out at the time were amazed at the amount of ducks that were in the area and on the move through the skies, one survivor recounting there were thousands. Future Minnesota Vikings coach Bud Grant was caught in this storm.

Casualties

A total of 146 deaths were blamed on the storm, with the following instances being noteworthy: Additionally, 1.5 million turkeys intended for Thanksgiving dinners across Minnesota perished from exposure to the cold conditions.

Aftermath

Prior to this event, all of the weather forecasts for the region originated in Chicago. After the failure to provide an accurate forecast for this blizzard, forecasting responsibilities were expanded to include 24-hour coverage and more forecasting offices were created, yielding more accurate local forecasts. The U.S. Weather Bureau was criticized that it failed to predict the huge blizzard and officials released a statement that they were aware that the storm was coming but wrong about its strength and scope. The Twin Cities (Minneapolis/St. Paul) branch of Meteorology was upgraded to issue forecasts and not rely on the Chicago site.