Island Park weather by month
What a typical year looks like in Island Park, Idaho: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Island Park, 13 km from Island Park; records cover 1937–2026.
The year at a glance
- Precipitation a year
- 28.8 in732 mm
- Snow a year
- Rare
- Last spring freeze
- Jun 21
- First fall freeze
- Jul 28
- Heating degree days
- 10,272
- Cooling degree days
- 23
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −19°−28° (heating, 99%) and 89°32° (cooling, 1%).
Month by month
Island Park in January
Highs average 27°−3° and lows 6°−14°, with 3.5 in90 mm of precipitation in a typical January.
- Record high
- 49°9° (1981)
- Record low
- −60°−51° (1943)
- Heating degree days
- 1513
- Cooling degree days
- 0
Island Park in February
Highs average 30°−1° and lows 8°−14°, with 2.6 in67 mm of precipitation in a typical February.
- Record high
- 55°13° (1963)
- Record low
- −54°−48° (1982)
- Heating degree days
- 1299
- Cooling degree days
- 0
Island Park in March
Highs average 39°4° and lows 15°−10°, with 2.1 in52 mm of precipitation in a typical March.
- Record high
- 68°20° (2026)
- Record low
- −36°−38° (1955)
- Heating degree days
- 1192
- Cooling degree days
- 0
Island Park in April
Highs average 47°9° and lows 23°−5°, with 2.4 in60 mm of precipitation in a typical April.
- Record high
- 76°24° (1985)
- Record low
- −18°−28° (1975)
- Heating degree days
- 892
- Cooling degree days
- 0
Island Park in May
Highs average 59°15° and lows 32°0°, with 3 in76 mm of precipitation in a typical May.
- Record high
- 84°29° (1986)
- Record low
- 7°−14° (1967)
- Heating degree days
- 609
- Cooling degree days
- 0
Island Park in June
Highs average 67°20° and lows 38°3°, with 2.6 in67 mm of precipitation in a typical June.
- Record high
- 91°33° (2002)
- Record low
- 20°−7° (1983)
- Heating degree days
- 375
- Cooling degree days
- 1
Island Park in July
Highs average 77°25° and lows 43°6°, with 1.2 in30 mm of precipitation in a typical July.
- Record high
- 97°36° (1996)
- Record low
- 25°−4° (1943)
- Heating degree days
- 170
- Cooling degree days
- 14
Island Park in August
Highs average 77°25° and lows 40°4°, with 1.1 in29 mm of precipitation in a typical August.
- Record high
- 96°36° (1961)
- Record low
- 17°−8° (1992)
- Heating degree days
- 206
- Cooling degree days
- 8
Island Park in September
Highs average 68°20° and lows 32°0°, with 1.7 in42 mm of precipitation in a typical September.
- Record high
- 91°33° (1950)
- Record low
- 8°−13° (1983)
- Heating degree days
- 448
- Cooling degree days
- 0
Island Park in OctoberThis month
Highs average 51°11° and lows 24°−4°, with 2.1 in53 mm of precipitation in a typical October.
- Record high
- 82°28° (2010)
- Record low
- −17°−27° (2019)
- Heating degree days
- 846
- Cooling degree days
- 0
Island Park in November
Highs average 36°2° and lows 14°−10°, with 2.5 in65 mm of precipitation in a typical November.
- Record high
- 68°20° (1999)
- Record low
- −34°−37° (1955)
- Heating degree days
- 1202
- Cooling degree days
- 0
Island Park in December
Highs average 26°−4° and lows 6°−14°, with 4 in102 mm of precipitation in a typical December.
- Record high
- 56°13° (1939)
- Record low
- −51°−46° (1964)
- Heating degree days
- 1520
- Cooling degree days
- 0