Grass Lake weather by month
What a typical year looks like in Grass Lake, Michigan: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Chelsea, 18 km from Grass Lake; records cover 2001–2026.
The year at a glance
- Precipitation a year
- 34.7 in881 mm
- Snow a year
- 33 in84 cm
- Last spring freeze
- May 6
- First fall freeze
- Oct 14
- Heating degree days
- 6,653
- Cooling degree days
- 610
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −5°−21° (heating, 99%) and 92°33° (cooling, 1%).
Month by month
Grass Lake in January
Highs average 31°−1° and lows 16°−9°, with 2.4 in61 mm of precipitation and 11 in28 cm of snow in a typical January.
- Record high
- 62°17° (2008)
- Record low
- −21°−29° (2026)
- Heating degree days
- 1286
- Cooling degree days
- 0
Grass Lake in February
Highs average 34°1° and lows 17°−8°, with 2 in50 mm of precipitation and 9 in22 cm of snow in a typical February.
- Record high
- 72°22° (2024)
- Record low
- −25°−32° (2015)
- Heating degree days
- 1100
- Cooling degree days
- 0
Grass Lake in March
Highs average 44°7° and lows 25°−4°, with 2.2 in57 mm of precipitation and 5 in12 cm of snow in a typical March.
- Record high
- 87°31° (2012)
- Record low
- −10°−23° (2003)
- Heating degree days
- 935
- Cooling degree days
- 1
Grass Lake in April
Highs average 58°14° and lows 37°3°, with 3 in76 mm of precipitation and 0.9 in2.3 cm of snow in a typical April.
- Record high
- 86°30° (2002)
- Record low
- 15°−9° (2016)
- Heating degree days
- 543
- Cooling degree days
- 4
Grass Lake in May
Highs average 70°21° and lows 48°9°, with 3.8 in97 mm of precipitation in a typical May.
- Record high
- 95°35° (2018)
- Record low
- 25°−4° (2005)
- Heating degree days
- 236
- Cooling degree days
- 36
Grass Lake in June
Highs average 79°26° and lows 57°14°, with 3.6 in92 mm of precipitation in a typical June.
- Record high
- 99°37° (2012)
- Record low
- 38°3° (2003)
- Heating degree days
- 47
- Cooling degree days
- 127
Grass Lake in July
Highs average 82°28° and lows 61°16°, with 3.5 in88 mm of precipitation in a typical July.
- Record high
- 101°38° (2012)
- Record low
- 44°7° (2007)
- Heating degree days
- 12
- Cooling degree days
- 211
Grass Lake in August
Highs average 80°27° and lows 59°15°, with 3.6 in90 mm of precipitation in a typical August.
- Record high
- 96°36° (2012)
- Record low
- 41°5° (2025)
- Heating degree days
- 19
- Cooling degree days
- 164
Grass Lake in September
Highs average 74°23° and lows 51°11°, with 2.7 in70 mm of precipitation in a typical September.
- Record high
- 94°34° (2017)
- Record low
- 31°−1° (2020)
- Heating degree days
- 134
- Cooling degree days
- 60
Grass Lake in OctoberThis month
Highs average 61°16° and lows 40°5°, with 3.1 in80 mm of precipitation in a typical October.
- Record high
- 88°31° (2007)
- Record low
- 22°−6° (2008)
- Heating degree days
- 453
- Cooling degree days
- 7
Grass Lake in November
Highs average 47°8° and lows 31°−1°, with 2.6 in66 mm of precipitation and 1.8 in4.6 cm of snow in a typical November.
- Record high
- 78°26° (2020)
- Record low
- 0°−18° (2019)
- Heating degree days
- 780
- Cooling degree days
- 0
Grass Lake in December
Highs average 36°2° and lows 23°−5°, with 2.1 in53 mm of precipitation and 6 in15 cm of snow in a typical December.
- Record high
- 68°20° (2001)
- Record low
- −16°−27° (2017)
- Heating degree days
- 1108
- Cooling degree days
- 0