Weather
Maine Fall Begins With Frost and Upper 20s
Caribou, Maine – Fall begins Tuesday night with northern Maine facing its coldest night of the season so far, including frost and lows in the upper 20s.
By Wesley Grant · 2026-09-22T08:52:55.581Z
Caribou, Maine – Fall begins Tuesday night with northern Maine facing its coldest night of the season so far, including frost and lows in the upper 20s.
According to the National Weather Service in Caribou, the autumnal equinox occurs at 8:05 p.m. Tuesday. Temperatures will tumble after mostly sunny conditions and highs in the 60s during the day.
The coldest conditions will develop across northern portions of the state. Lows there should fall into the upper 20s and lower 30s, cold enough for frost to develop across the area.
Southern portions of the region will remain somewhat warmer, with overnight temperatures expected in the upper 30s to around 40 degrees.
The timing makes the temperature drop especially notable. Astronomical fall officially starts Tuesday evening, just hours before the region experiences what the Weather Service expects to be its coldest night of the season to date.
Residents in colder northern communities should consider protecting sensitive outdoor plants and other vegetation from frost before temperatures fall Tuesday night. Anyone heading out early Wednesday should also prepare for temperatures near or below freezing.
Dry weather will dominate through the end of the workweek. The Weather Service expects sunny conditions, with temperatures returning to near normal levels by Thursday.
Attention then turns to the coast for the weekend. The Weather Service is tracking a possible coastal storm, but emphasized that its track and development remain highly uncertain.
For now, northern Maine's first night of astronomical fall will bring the more immediate weather concern: widespread cold, frost and temperatures potentially dipping into the upper 20s before conditions moderate toward Thursday.