Autumn is a transitional season when the heat of summer fades away and the chill of winter gradually returns. But, sometimes winter can be aggressive and show up overnight.

When this type of rapid temperature change happens, it is often called a Blue Norther. This is a fast-moving cold front marked by a quick and dramatic drop in temperature. A fall of 20 to 30 degrees in just a few minutes is not uncommon. They also usher in a dark blue sky and strong northerly winds. Hence, the name.

Blue Northers are most common in the central US, where there are few natural barriers to slow or block arctic air masses from moving south. They can occur throughout the year, but are most common between November and March.

One of the most famous examples of this weather phenomenon was the “Great Blue Norther” of November 11, 1911. As the front passed through the southern plains, temperatures dropped from highs in the 70s and 80s to the teens in just ten hours. In Oklahoma City, for example, the temperature reached a record high of 83°F in the afternoon and then plummeted to a record low of 17°F by midnight. Both records, according to the NWS, are still in place.

Twenty-four temperature changes from The Great Blue Norther of 1911. Credit: FOX