Weather
Upper Michigan Fall Begins With Frost Near 36 Degrees
Marquette, Michigan – Fall begins Tuesday with frost and freeze concerns across Upper Michigan before temperatures climb toward 70 degrees by Friday.
By Blake Harrison · 2026-09-22T08:55:01.173Z
Marquette, Michigan – Fall begins Tuesday with frost and freeze concerns across Upper Michigan before temperatures climb toward 70 degrees by Friday.
According to the National Weather Service in Marquette, high pressure will keep the region dry through the week. Frost and freezing temperatures occurred Tuesday morning, and some areas could see frost again Wednesday morning.
The Weather Service said lows can fall into the mid 30s away from the Great Lakes. Frost concerns begin around 36 degrees because local cold pockets and elevated surfaces can cool to freezing even when the measured air temperature remains slightly higher.
Residents with sensitive outdoor plants should consider protecting them before temperatures fall Tuesday night, particularly in colder inland locations.
Despite the chilly mornings, afternoons will trend warmer during the first several days of astronomical fall. Regional temperatures reach about 61 degrees Tuesday before climbing to around 63 Wednesday and 65 Thursday.
By Friday, the regional high reaches about 68 degrees, with some locations potentially approaching 70. High pressure nearby will also keep rain out of the picture through the workweek.
The difference between morning lows and afternoon highs will make for a pronounced early fall temperature swing. Jackets may be needed during the morning, while afternoons become progressively milder through Friday.
The immediate concern is Wednesday morning's frost potential, especially away from the moderating influence of the Great Lakes. After that cold start, Upper Michigan should remain dry while daytime temperatures steadily rise through Friday.