Just after 7:00 p.m. CDT (00:00 UTC), skies in Rochester assumed a greenish tint, and a rumbling sound became audible. The "roar" of the tornado gave many residents advance warning. "Dense darkness" enveloped the city as the tornado struck. In just five minutes, the tornado passed through the north side of Rochester, causing devastating damage. The northern third of Rochester was devastated, with 135 homes destroyed and 200 damaged. The tornado also caused extensive damage to a swath that extended eastward from Rochester.