Reserve weather by month
What a typical year looks like in Reserve, Montana: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Medicine Lake 3 SE, 13 km from Reserve; records cover 1911–2025.
The year at a glance
- Precipitation a year
- 14.1 in357 mm
- Snow a year
- Rare
- Last spring freeze
- May 15
- First fall freeze
- Sep 19
- Heating degree days
- 9,091
- Cooling degree days
- 385
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −26°−32° (heating, 99%) and 96°36° (cooling, 1%).
Month by month
Reserve in January
Highs average 22°−5° and lows 0°−18°, with 0.33 in8.4 mm of precipitation in a typical January.
- Record high
- 60°16° (2002)
- Record low
- −51°−46° (1916)
- Heating degree days
- 1674
- Cooling degree days
- 0
Reserve in February
Highs average 26°−3° and lows 4°−16°, with 0.16 in4.1 mm of precipitation in a typical February.
- Record high
- 68°20° (1932)
- Record low
- −58°−50° (1936)
- Heating degree days
- 1396
- Cooling degree days
- 0
Reserve in March
Highs average 39°4° and lows 16°−9°, with 0.42 in11 mm of precipitation in a typical March.
- Record high
- 77°25° (1928)
- Record low
- −38°−39° (1916)
- Heating degree days
- 1158
- Cooling degree days
- 0
Reserve in April
Highs average 55°13° and lows 30°−1°, with 0.93 in24 mm of precipitation in a typical April.
- Record high
- 92°33° (1926)
- Record low
- −15°−26° (1975)
- Heating degree days
- 688
- Cooling degree days
- 0
Reserve in May
Highs average 67°19° and lows 41°5°, with 2.4 in61 mm of precipitation in a typical May.
- Record high
- 103°39° (1934)
- Record low
- 8°−13° (2005)
- Heating degree days
- 353
- Cooling degree days
- 10
Reserve in June
Highs average 75°24° and lows 51°10°, with 2.9 in74 mm of precipitation in a typical June.
- Record high
- 107°42° (1988)
- Record low
- 22°−6° (1915)
- Heating degree days
- 118
- Cooling degree days
- 54
Reserve in July
Highs average 83°28° and lows 56°13°, with 2.7 in67 mm of precipitation in a typical July.
- Record high
- 117°47° (1937)
- Record low
- 30°−1° (1934)
- Heating degree days
- 30
- Cooling degree days
- 158
Reserve in August
Highs average 83°28° and lows 53°12°, with 1.5 in39 mm of precipitation in a typical August.
- Record high
- 107°42° (1949)
- Record low
- 30°−1° (1911)
- Heating degree days
- 52
- Cooling degree days
- 138
Reserve in September
Highs average 72°22° and lows 42°6°, with 1.2 in30 mm of precipitation in a typical September.
- Record high
- 101°38° (1921)
- Record low
- 9°−13° (1926)
- Heating degree days
- 263
- Cooling degree days
- 24
Reserve in OctoberThis month
Highs average 55°13° and lows 29°−1°, with 0.89 in23 mm of precipitation in a typical October.
- Record high
- 91°33° (1989)
- Record low
- −10°−23° (1935)
- Heating degree days
- 703
- Cooling degree days
- 1
Reserve in November
Highs average 38°3° and lows 16°−9°, with 0.36 in9.1 mm of precipitation in a typical November.
- Record high
- 75°24° (1990)
- Record low
- −31°−35° (1921)
- Heating degree days
- 1140
- Cooling degree days
- 0
Reserve in December
Highs average 27°−3° and lows 5°−15°, with 0.32 in8.1 mm of precipitation in a typical December.
- Record high
- 68°20° (1939)
- Record low
- −46°−43° (1983)
- Heating degree days
- 1516
- Cooling degree days
- 0