Good morning and further north in Michigan, the temperature fell to 20°F. in the town of Grayling.
and also 18°F at Roscommon, but I have my doubts about this value.
you similarly send me photos of your autumnal landscape unfortunately here this morning no frost the temperature went down to 39°F but elsewhere in France it froze notably in "Le Chesne" where it was 32°F ( 541 ft)
At the beginning of October we could have an increase of the temperature because of a hurricane which would come to position itself on the Azores to follow... but yes indeed a clear night without wind favors the descent of the temperatures