Iowa has had tornadoes reported in every month over the years. That includes winter months, although, as you can imagine, they are not common. January 24, 1967 was the date January made it into the books.
A broken line of supercell thunderstorms (strong, long-lived thunderstorms) developed along a cold front. Thirteen tornadoes were reported in Iowa that day with most creating F2 damage. However, two occurred that had F3 strength.
Eleven injuries were reported in Iowa with one death: A child was killed in an F3 tornado west of Fort Madison.
More tornadoes were reported with the same system in Missouri and Illinois with more injuries but no additional deaths. If you want to read more about this tornadic outbreak, click here.
More typical January weather tracked into the area by the 26th, leaving over a foot of snow in the Burlington area!
Tornadoes can, and have occurred in all months of the year in Iowa. January and February ones are rare and have not been recorded here since before 1980. For climatology regarding tornadoes between 1980 and 2016, click here.