1998 Comfrey–St. Peter tornado outbreak

The 1998 Comfrey–St. Peter tornado outbreak was an unseasonably-strong tornado outbreak which affected the Upper Midwest region of the United States on March 29, 1998. A strong area of low pressure combined with a warm front and favorable upper-level dynamics to produce 16 tornadoes across the region—14 in Minnesota and two in Wisconsin. Thirteen of the tornadoes in Minnesota were spawned by a single supercell thunderstorm. This supercell remained intact for approximately 150 miles (240 km) as it moved across the southern part of the state during the late-afternoon hours.

Over $235 million in damage (1998 US$) was recorded from the tornadoes, two people were killed, and 21 others were injured. Most of the damage was caused by three tornadoes—one rated F4 on the Fujita scale that hit the town of Comfrey, Minnesota, an F3 that hit St. Peter, Minnesota, and an F2 that hit Le Center, Minnesota. Gustavus Adolphus College in St. Peter was especially hard-hit, with several buildings damaged or destroyed, 2,000 trees lost, and nearly 80% of the windows on the campus shattered. In Comfrey, 75% of the structures in the town were damaged or destroyed, including the local K–12 school. Seven counties in southern Minnesota were later declared federal disaster areas.

The outbreak broke many early-season tornado records for the state of Minnesota. The 14 total tornadoes in the state were the most to ever touch down on a single day in March. The F4 tornado was the strongest ever recorded in the state in March, and its 67-mile (108 km) path the longest tornado path ever recorded in Minnesota. In December 1998, the United States Department of Commerce awarded a bronze medal to the Twin Cities office of the National Weather Service (NWS) for providing excellent service to the public during the outbreak event.