I know that it is unusual to have lightning and thunder in winter, but didn’t the past winter produce thunderstorms in December, January and February. Has that ever happened before?
Gary L. Goldblatt
You are correct that thunder did occur in all months last winter. It is quite a rare occurrence, and dating back to 1871, it has only happened four other times according to Chicago weather historian Frank Wachowski. Wachowski reported that the only winters laying claim to a thunderstorm trifecta were 1931-32, 1949-50, 1967-68, 1974-75 and last winter 2017-18. While winter thunderstorms can be accompanied by either rain or snow, last winter’s all occurred on unseasonably mild, rainy days. Thunder was reported on December 4 with a high of 65 degrees, January 22 when it was 54 degrees and February 20 when the mercury peaked at 66 degrees.