Clayton weather by month
What a typical year looks like in Clayton, Washington: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at Deer Park Airport, 10 km from Clayton; records cover 1998–2026.
The year at a glance
- Precipitation a year
- 22.5 in572 mm
- Snow a year
- Rare
- Last spring freeze
- May 25
- First fall freeze
- Sep 11
- Heating degree days
- 7,286
- Cooling degree days
- 216
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are −2°−19° (heating, 99%) and 96°36° (cooling, 1%).
Month by month
Clayton in January
Highs average 34°1° and lows 21°−6°, with 2.9 in73 mm of precipitation in a typical January.
- Record high
- 54°12° (2003)
- Record low
- −28°−33° (2004)
- Heating degree days
- 1162
- Cooling degree days
- 0
Clayton in February
Highs average 39°4° and lows 22°−6°, with 1.6 in41 mm of precipitation in a typical February.
- Record high
- 60°16° (2020)
- Record low
- −14°−26° (2018)
- Heating degree days
- 974
- Cooling degree days
- 0
Clayton in March
Highs average 49°9° and lows 27°−3°, with 2.3 in58 mm of precipitation in a typical March.
- Record high
- 74°23° (2025)
- Record low
- −12°−24° (2009)
- Heating degree days
- 851
- Cooling degree days
- 0
Clayton in April
Highs average 58°14° and lows 32°0°, with 1.9 in49 mm of precipitation in a typical April.
- Record high
- 85°29° (2016)
- Record low
- 13°−11° (2008)
- Heating degree days
- 609
- Cooling degree days
- 0
Clayton in May
Highs average 67°20° and lows 39°4°, with 1.9 in49 mm of precipitation in a typical May.
- Record high
- 91°33° (2006)
- Record low
- 18°−8° (2013)
- Heating degree days
- 367
- Cooling degree days
- 4
Clayton in June
Highs average 73°23° and lows 44°7°, with 1.9 in49 mm of precipitation in a typical June.
- Record high
- 111°44° (2021)
- Record low
- 29°−2° (2026)
- Heating degree days
- 212
- Cooling degree days
- 18
Clayton in July
Highs average 84°29° and lows 48°9°, with 0.61 in15 mm of precipitation in a typical July.
- Record high
- 106°41° (2021)
- Record low
- 32°0° (2006)
- Heating degree days
- 59
- Cooling degree days
- 99
Clayton in August
Highs average 84°29° and lows 47°8°, with 0.73 in19 mm of precipitation in a typical August.
- Record high
- 105°41° (2018)
- Record low
- 31°−1° (2010)
- Heating degree days
- 66
- Cooling degree days
- 81
Clayton in September
Highs average 74°23° and lows 40°4°, with 0.82 in21 mm of precipitation in a typical September.
- Record high
- 100°38° (2025)
- Record low
- 18°−8° (2000)
- Heating degree days
- 256
- Cooling degree days
- 14
Clayton in OctoberThis month
Highs average 58°14° and lows 32°0°, with 2 in51 mm of precipitation in a typical October.
- Record high
- 83°28° (2022)
- Record low
- 0°−18° (2002)
- Heating degree days
- 632
- Cooling degree days
- 0
Clayton in November
Highs average 42°5° and lows 26°−3°, with 2.8 in70 mm of precipitation in a typical November.
- Record high
- 64°18° (1999)
- Record low
- −17°−27° (2010)
- Heating degree days
- 926
- Cooling degree days
- 0
Clayton in December
Highs average 33°1° and lows 21°−6°, with 3.1 in78 mm of precipitation in a typical December.
- Record high
- 59°15° (2021)
- Record low
- −17°−27° (2008)
- Heating degree days
- 1172
- Cooling degree days
- 0