Thomaston weather by month
What a typical year looks like in Thomaston, Maine: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at West Rockport 1 Nnw, 13 km from Thomaston; records cover 1976–2026.
The year at a glance
- Precipitation a year
- 56.2 in1427 mm
- Snow a year
- 69 in174 cm
- Last spring freeze
- Apr 30
- First fall freeze
- Oct 22
- Heating degree days
- 7,396
- Cooling degree days
- 311
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −6°−21° (heating, 99%) and 88°31° (cooling, 1%).
Month by month
Thomaston in January
Highs average 30°−1° and lows 12°−11°, with 4.8 in121 mm of precipitation and 17 in44 cm of snow in a typical January.
- Record high
- 59°15° (2008)
- Record low
- −22°−30° (1984)
- Heating degree days
- 1359
- Cooling degree days
- 0
Thomaston in February
Highs average 33°0° and lows 14°−10°, with 4.2 in107 mm of precipitation and 19 in49 cm of snow in a typical February.
- Record high
- 65°18° (2022)
- Record low
- −20°−29° (2003)
- Heating degree days
- 1175
- Cooling degree days
- 0
Thomaston in March
Highs average 40°4° and lows 22°−5°, with 5 in127 mm of precipitation and 11 in29 cm of snow in a typical March.
- Record high
- 84°29° (2012)
- Record low
- −11°−24° (1996)
- Heating degree days
- 1057
- Cooling degree days
- 0
Thomaston in April
Highs average 51°11° and lows 34°1°, with 5.2 in132 mm of precipitation and 4 in9 cm of snow in a typical April.
- Record high
- 83°28° (1998)
- Record low
- 10°−12° (1995)
- Heating degree days
- 675
- Cooling degree days
- 0
Thomaston in May
Highs average 62°17° and lows 44°7°, with 4.2 in107 mm of precipitation in a typical May.
- Record high
- 95°35° (1992)
- Record low
- 21°−6° (1986)
- Heating degree days
- 371
- Cooling degree days
- 6
Thomaston in June
Highs average 71°22° and lows 54°12°, with 4.5 in114 mm of precipitation in a typical June.
- Record high
- 96°36° (2025)
- Record low
- 35°2° (2020)
- Heating degree days
- 126
- Cooling degree days
- 40
Thomaston in July
Highs average 77°25° and lows 60°15°, with 3.2 in81 mm of precipitation in a typical July.
- Record high
- 96°36° (1991)
- Record low
- 43°6° (1980)
- Heating degree days
- 26
- Cooling degree days
- 124
Thomaston in August
Highs average 76°25° and lows 59°15°, with 3.4 in86 mm of precipitation in a typical August.
- Record high
- 93°34° (1988)
- Record low
- 37°3° (1989)
- Heating degree days
- 26
- Cooling degree days
- 111
Thomaston in September
Highs average 69°21° and lows 52°11°, with 4.5 in114 mm of precipitation in a typical September.
- Record high
- 91°33° (2010)
- Record low
- 28°−2° (1980)
- Heating degree days
- 165
- Cooling degree days
- 29
Thomaston in OctoberThis month
Highs average 57°14° and lows 41°5°, with 6.1 in154 mm of precipitation and 0.2 in0.5 cm of snow in a typical October.
- Record high
- 84°29° (2025)
- Record low
- 14°−10° (1993)
- Heating degree days
- 495
- Cooling degree days
- 1
Thomaston in November
Highs average 47°8° and lows 31°0°, with 5.3 in134 mm of precipitation and 2.3 in5.8 cm of snow in a typical November.
- Record high
- 75°24° (2024)
- Record low
- 4°−16° (1989)
- Heating degree days
- 783
- Cooling degree days
- 0
Thomaston in December
Highs average 36°2° and lows 20°−7°, with 5.9 in150 mm of precipitation and 15 in38 cm of snow in a typical December.
- Record high
- 63°17° (1998)
- Record low
- −25°−32° (1980)
- Heating degree days
- 1138
- Cooling degree days
- 0