Herron Island weather by month
What a typical year looks like in Herron Island, Washington: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Shelton Airport, 24 km from Herron Island; records cover 1998–2026.
The year at a glance
- Precipitation a year
- 67.9 in1725 mm
- Snow a year
- Rare
- Last spring freeze
- May 6
- First fall freeze
- Oct 9
- Heating degree days
- 5,082
- Cooling degree days
- 150
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 19°−7° (heating, 99%) and 93°34° (cooling, 1%).
Month by month
Herron Island in January
Highs average 47°8° and lows 34°1°, with 11.1 in281 mm of precipitation in a typical January.
- Record high
- 61°16° (2005)
- Record low
- 8°−13° (2004)
- Heating degree days
- 764
- Cooling degree days
- 0
Herron Island in February
Highs average 50°10° and lows 33°1°, with 6.7 in169 mm of precipitation in a typical February.
- Record high
- 65°18° (2015)
- Record low
- 9°−13° (2014)
- Heating degree days
- 651
- Cooling degree days
- 0
Herron Island in March
Highs average 55°13° and lows 35°2°, with 7.2 in184 mm of precipitation in a typical March.
- Record high
- 80°27° (2019)
- Record low
- 16°−9° (2019)
- Heating degree days
- 623
- Cooling degree days
- 0
Herron Island in April
Highs average 60°15° and lows 38°3°, with 4.9 in123 mm of precipitation in a typical April.
- Record high
- 87°31° (2016)
- Record low
- 23°−5° (2020)
- Heating degree days
- 482
- Cooling degree days
- 0
Herron Island in May
Highs average 67°19° and lows 44°7°, with 2.6 in67 mm of precipitation in a typical May.
- Record high
- 91°33° (2005)
- Record low
- 28°−2° (2006)
- Heating degree days
- 302
- Cooling degree days
- 3
Herron Island in June
Highs average 72°22° and lows 49°9°, with 1.5 in39 mm of precipitation in a typical June.
- Record high
- 110°43° (2021)
- Record low
- 33°1° (2023)
- Heating degree days
- 165
- Cooling degree days
- 16
Herron Island in July
Highs average 78°26° and lows 52°11°, with 0.68 in17 mm of precipitation in a typical July.
- Record high
- 104°40° (2009)
- Record low
- 38°3° (2009)
- Heating degree days
- 55
- Cooling degree days
- 58
Herron Island in August
Highs average 79°26° and lows 52°11°, with 1.2 in31 mm of precipitation in a typical August.
- Record high
- 101°38° (2014)
- Record low
- 38°3° (2010)
- Heating degree days
- 48
- Cooling degree days
- 59
Herron Island in September
Highs average 74°23° and lows 48°9°, with 2.5 in64 mm of precipitation in a typical September.
- Record high
- 97°36° (2024)
- Record low
- 31°−1° (2023)
- Heating degree days
- 149
- Cooling degree days
- 14
Herron Island in OctoberThis month
Highs average 62°16° and lows 41°5°, with 7 in178 mm of precipitation in a typical October.
- Record high
- 87°31° (2022)
- Record low
- 17°−8° (2002)
- Heating degree days
- 425
- Cooling degree days
- 0
Herron Island in November
Highs average 52°11° and lows 36°2°, with 11.6 in295 mm of precipitation in a typical November.
- Record high
- 72°22° (2010)
- Record low
- 9°−13° (2010)
- Heating degree days
- 628
- Cooling degree days
- 0
Herron Island in December
Highs average 46°8° and lows 33°1°, with 10.9 in277 mm of precipitation in a typical December.
- Record high
- 60°16° (2014)
- Record low
- 6°−14° (1998)
- Heating degree days
- 790
- Cooling degree days
- 0