Hysham weather by month
What a typical year looks like in Hysham, Montana: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Hysham, 0 km from Hysham; records cover 1945–2026.
The year at a glance
- Precipitation a year
- 14.9 in379 mm
- Snow a year
- 37 in94 cm
- Last spring freeze
- May 11
- First fall freeze
- Sep 28
- Heating degree days
- 7,011
- Cooling degree days
- 575
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −15°−26° (heating, 99%) and 97°36° (cooling, 1%).
Month by month
Hysham in January
Highs average 35°2° and lows 12°−11°, with 0.61 in15 mm of precipitation and 8 in21 cm of snow in a typical January.
- Record high
- 72°22° (1992)
- Record low
- −48°−44° (1954)
- Heating degree days
- 1285
- Cooling degree days
- 0
Hysham in February
Highs average 39°4° and lows 15°−9°, with 0.58 in15 mm of precipitation and 5 in14 cm of snow in a typical February.
- Record high
- 75°24° (1992)
- Record low
- −38°−39° (1971)
- Heating degree days
- 1064
- Cooling degree days
- 0
Hysham in March
Highs average 51°10° and lows 24°−5°, with 0.8 in20 mm of precipitation and 6 in14 cm of snow in a typical March.
- Record high
- 85°29° (2025)
- Record low
- −36°−38° (2019)
- Heating degree days
- 863
- Cooling degree days
- 0
Hysham in April
Highs average 61°16° and lows 33°1°, with 1.7 in44 mm of precipitation and 2.5 in6.4 cm of snow in a typical April.
- Record high
- 97°36° (1952)
- Record low
- 4°−16° (2013)
- Heating degree days
- 548
- Cooling degree days
- 1
Hysham in May
Highs average 70°21° and lows 43°6°, with 2.5 in63 mm of precipitation and 0.8 in2 cm of snow in a typical May.
- Record high
- 100°38° (1980)
- Record low
- 14°−10° (1954)
- Heating degree days
- 288
- Cooling degree days
- 14
Hysham in June
Highs average 79°26° and lows 52°11°, with 2.2 in56 mm of precipitation in a typical June.
- Record high
- 107°42° (2021)
- Record low
- 29°−2° (1969)
- Heating degree days
- 74
- Cooling degree days
- 80
Hysham in July
Highs average 88°31° and lows 58°14°, with 1.5 in38 mm of precipitation in a typical July.
- Record high
- 111°44° (1947)
- Record low
- 37°3° (1972)
- Heating degree days
- 11
- Cooling degree days
- 245
Hysham in August
Highs average 86°30° and lows 55°13°, with 1.2 in29 mm of precipitation in a typical August.
- Record high
- 108°42° (1949)
- Record low
- 32°0° (1992)
- Heating degree days
- 24
- Cooling degree days
- 196
Hysham in September
Highs average 75°24° and lows 46°8°, with 1.4 in36 mm of precipitation and 0.1 in0.3 cm of snow in a typical September.
- Record high
- 105°41° (1983)
- Record low
- 19°−7° (1985)
- Heating degree days
- 175
- Cooling degree days
- 37
Hysham in OctoberThis month
Highs average 60°16° and lows 34°1°, with 1.4 in35 mm of precipitation and 2.7 in6.9 cm of snow in a typical October.
- Record high
- 93°34° (1980)
- Record low
- −9°−23° (1991)
- Heating degree days
- 550
- Cooling degree days
- 2
Hysham in November
Highs average 47°8° and lows 23°−5°, with 0.59 in15 mm of precipitation and 4 in11 cm of snow in a typical November.
- Record high
- 79°26° (1999)
- Record low
- −31°−35° (1985)
- Heating degree days
- 903
- Cooling degree days
- 0
Hysham in December
Highs average 36°2° and lows 15°−10°, with 0.48 in12 mm of precipitation and 8 in19 cm of snow in a typical December.
- Record high
- 70°21° (1980)
- Record low
- −46°−43° (1989)
- Heating degree days
- 1226
- Cooling degree days
- 0