September 24-26, 1942 Snowstorm:  
Earliest Measurable Snow for the Area 

From September 24th through the 26th, 1942, an early season winter storm moved through the Northern Plains, Upper Mississippi River Valley, and Great Lakes, dropping measurable snow as as it went.  In many places across Minnesota, Iowa, Wisconsin, and northern Illinois, this was their earliest measurable snow on record.  The highest snowfall total was 9 inches at Sauk Centre, MN.  Parts of northern Missouri saw their earliest traces of snow. 

Meteorological setup

Prior to the storm's passage through the Northern Plains, Upper Mississippi River Valley, and Great Lakes, an abnormally cool air mass resided across these regions.  High temperatures were mainly in the 30s and 40s.  This was 20 to 30 degrees below the late September normals.

A surface low pressure system moved southeast through southern Alberta and western North Dakota during the evening of September 24th and the early morning hours of September 25th.  This low then moved east southeast across southern North Dakota and northeast South Dakota during the late morning and afternoon of the 25th.  By 7:30 PM, the low was located just north of Aberdeen, South Dakota. 

During the late evening of the 25th and early morning hours of the 26th, the surface low continued to move east southeast across southern Minnesota and southern Wisconsin.  By 7:30 AM on September 26th, the surface low was located near Madison, WI. This low then began moving east northeast across southeast Wisconsin and central lower Michigan during the late morning and afternoon.  By 7:30 PM on the 26th, the low was located just north of Georgian Bay.

 
September 25, 1942 at 730 PM

What happened in the states impacted?

North Dakota...

The highest snowfall recorded in September occurred  on the 25th and 26th - heaviest in the central part of the state.  Many tree branches and shrubs were broken by the weight of the snow.  Threshing was seriously delayed by the wet weather.  Following the snow, a severe freeze on the 26th through 28th froze the ground to a depth of 3 inches in a few localities.  Gardens were destroyed and considerable corn and flax were damaged.  Parshall's (Mountrail County) low temperature on the morning of the 26th fell to 4 degrees.

Minnesota...

On the 25th and 26th, a destructive sleet, snow, and windstorm in west-central counties caused a loss estimated at $25,000 to overhead wire systems.  Also, there was damage to trees and shrubbery from the weight of moist snow.  The snowfall was the heaviest ever experienced so early in the season in this section of the state.  At Bird Island 8.0 inches of snow fell, and at Sauk Centre an unofficial measurement of 9.0 inches was reported.  The snow fell across most of the state, and new records for September snowfall were established at all southern stations and at some northern stations. 

• In Winona and along the river the snow melted rapidly on the pavement.  At both Lewiston and St. Charles, the snow was three inches deep on the lawns.
• Storm damage also crippled wire service mounted in Minnesota through the morning hours of the 26th.
• Mankato reported 2 inches of wet snow.  This downed many telephone wires, and tree branches broke under the weight of snow which brought down even more wires.
• Fairmont reported crop damage to soy and lima beans.  In addition, there were many wires down.
• Albert Lea reported 2 inches of snow.  This caused damage to the potato and onion crops along with much wire damage.
• Austin reported 4 inches of snow.  This brought down some power and telephone lines.  Telephone service between Rochester and Minneapolis was out during the morning of the 26th.
• Minneapolis and St. Paul had slippery snow-covered streets.  Several Friday night (September 25th) football games across the state were cancelled.

Iowa...

Snow fell over most of the state, but as temperatures were slightly above freezing at the surface, much of it melted as it fell.  However, in a large section of north central Iowa a considerable portion accumulated on the ground.  Four inches of snow were reported at Forest City, Mason City, and Allison.  The snow also fell more rapidly than it melted along the Missouri border with 4 inches at Millerton.  At that town it was estimated that only about half of the total snowfall accumulated on the ground.

The snow bent down soybeans, making combining difficult.  Most trees still retained their summer foliage so that the snow flakes clung to the leaves instead of sifting down through the branches, especially at Forest City, Centerville, Millerton, and Mason City.  At Cresco the weight of the snow caused a large tree to fall across Highway 9 and two men from Calmar, Iowa were killed when their tuck hit the fallen trunk.  There was some damage to light and communication wires, especially in the vicinity of Estherville and Mason City.

Illinois...

Snowfall varying from a trace to 3 inches fell from the 25th through the 26th over much of the north and central portions of the state.  The heaviest snow was found between Monmouth and Kankakee.  Both Dwight and Kankakee received the most snow (2.5 inches) in this band.

Wisconsin...

Unprecedented snow fell on the 26th and 27th.  Traces were generally found across southeastern part and in the river valleys of southwest Wisconsin.  Meanwhile 1 to 6 inches of snow fell across the remainder of the state.  The highest snowfall totals were reported at Tomahawk (5.7 inches) and Deerskin Dam (6.3 inches).  The average snowfall for the state was 0.8 inches.  The previous highest average for September was 0.1 inches in September 1899, 1908, and 1913.

Michigan...

On the 26th and 27th, unusually early snow fell across almost all parts of the state.  Much of the snow melted as it fell.  However, snowfall totaling more than 2 inches were reported at several stations in Upper Michigan and a few locations in northern lower Michigan.  The greatest accumulated snowfall occurred at Dukes (8 inches).

Indiana...

On the 25th and 26th, measurable snow fell across the northeast part of the state.  The heaviest totals was 4.0 inches in LaPorte and Wheatfield.

Local snowfall amounts...

                                Snowfall
Location         State            Total
--------         -----          --------
Grand Meadow       MN           5.0 inches
Medford            WI           4.5 inches
Austin             MN           4.0 inches
Neillsville        WI           4.0 inches
Spring Grove       MN           4.0 inches
Waukon             IA           3.5 inches
Mauston            WI           3.2 inches
Stanley            WI           3.2 inches
Blair              WI           3.0 inches
Lewiston           MN           3.0 inches
St Charles         MN           3.0 inches
Cresco             IA           2.5 inches
New Hampton        IA           2.5 inches
Mather             WI           2.0 inches
Reads              MN           2.0 inches
Elkader            IA           1.5 inches
Hillsboro          WI           1.5 inches
Postville          IA           1.5 inches
Fayette            IA           1.0 inches
Osage              IA           1.0 inches
Viroqua            WI           1.0 inches
Charles City       IA           0.4 inches
Rochester          MN           0.3 inches
La Crosse          WI           0.2 inches
Winona             MN           0.2 inches
Decorah            IA             Trace
Hatfield           WI             Trace
Lancaster          WI             Trace
Mondovi            WI             Trace
Oelwein            IA             Trace
Richland Center    WI             Trace
Wisconsin Dells    WI             Trace
Sparta             WI             Trace