The 1965 Twin Cities tornado outbreak was the outbreak of six strong tornadoes that occurred around Minneapolis and St. Paul, Minnesota, USA on May 6, 1965. It has been nicknamed "The Longest Night" and is most often remembered for the two F4 tornadoes that hit Fridley, Minnesota. Thirteen people were killed in the six tornadoes that touched down in the Twin Cities area that day. Four tornadoes were rated F4, one was rated F3, and other was rated F2. This event caused more dollar damage than any single weather event in Minnesota history at that time. It was voted a tie for the "fifth most significant Minnesota Weather Event of the 20th Century" with the 1965 Mississippi & Minnesota River Flooding by the Minnesota Climatology Office.

Temperatures on May 6 were in the upper 70s with high dewpoints, which was considered to be unusual for early May in Minnesota. A strong upper level system moving in from the southwest and a nearby slow-moving cold front helped spark the storms. These storms formed as training supercells; an atmospheric phenomenon that is extremely rare in Minnesota. Because of the training, the same general areas from Sibley County through Carver and Hennepin and into northwestern Ramsey counties kept getting the brunt of these cells.

Considering this outbreak occurred just three weeks after the Palm Sunday tornado outbreak, quick and successful warnings from the U.S. Weather Bureau and transmission from WCCO Radio kept the death toll relatively low. This was also the first time in Minnesota state history where civil defense sirens were used for severe weather purposes.

The first tornado touched down at 6:08 pm just east of the town of Cologne in Carver County. According to the U.S. Weather Bureau, this twister was rated an F4, killed three people, and injured 175. An F2 tornado that touched down in Sibley County at 6:43 pm killed one person and also injured 175 others.

Two tornadoes touched down in Fridley, just over an hour apart. In all, six people were killed in the Fridley tornadoes and over 180 were injured. Over 450 homes were destroyed in Fridley, and neighboring Mounds View also sustained heavy damage. A man who called WCCO radio after the first Fridley tornado claimed on air that he had been in his car when the tornado hit and that the tornado blew out his car windows. He escaped that incident without harm, but it is believed this same man was then killed by the second Fridley twister later that night. The tornado also damaged the sign adorning the Heights Theater in Columbia Heights. Photographs for the earlier Deephaven and second Fridley tornado were published in the Minneapolis Tribune (now Star Tribune) newspaper. Early radar images show the supercells as they moved through the area.