Clayton School · Photo: Ian Poellet · CC BY-SA 4.0Precipitation in Clayton trails that of 88% of U.S. towns: 23 inches a year
Midwinter brings lows of about 22°. Its July afternoons stay fresher than in 63% of U.S. towns. The latest 30-year average runs 1.3° warmer than 1901–2000’s, with January up the most. For walks and days out, the stretch from May to September brings highs of 67–84°.
A year in Clayton at a glance
Each month’s typical high and low, and what it brings.
What stands out about Clayton’s climate
Compared with towns across the U.S., with Clayton’s place in Washington beside it.
What a year in Clayton feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 112 frost-free days a year
In half of years the last 32° night comes by May 22 and the first by September 14. Frost and day counts come from NOAA’s station at Deer Park Airport, 6 miles from the town’s center, 100 ft lower.
The 2023 USDA map puts Clayton’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −5°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 48 inches of snow a winter
Snow, measured at Spokane Wfo, WA, falls mostly in December. Precipitation (rain plus melted snow) adds up to 23 inches a year; December is the wettest month and August the driest. Rain or snow falls on about 116 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Clayton
97% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Deer Park Airport.
Living with Clayton’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
112 frost-free days in zone 6a. The last frost comes by May 22 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Sep 14.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September.
Parks & trails →Of the yearly building losses FEMA expects in Clayton from natural hazards, river flooding is the largest share (41%); heat waves, cold waves, winter storms and ice storms together are 16%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Clayton and similar climates
TownRatings has no climate map of the towns around Clayton yet.
Climates most like Clayton’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Clayton, WA | 22° | 84° | 23" | 48" |
| Polson, MT | 20° | 83° | 19" | 34" |
| Castle Rock, CO | 18° | 85° | 18" | 58" |
| Los Alamos, NM | 19° | 85° | 15" | 42" |
| Doney Park, AZ | 17° | 86° | 16" | 52" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Clayton averaged 1.3° warmer than the 1900s. The biggest change is in January (+4.1°).
A smaller shift than in 52% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Clayton compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Clayton’s place among Washington’s.
Clayton weather by month
Highs, lows and precipitation from NOAA’s grid at Clayton’s center; snow, wet days and snow on the ground from Spokane Wfo, WA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 33° | 22° | 2.7" | 13.0" | 14 | 19 | 19° – 33° |
| February | 39° | 23° | 1.9" | 6.8" | 11 | 13 | 20° – 38° |
| March | 48° | 28° | 2.3" | 4.6" | 13 | 5 | 33° – 44° |
| April | 57° | 33° | 2.0" | 1.3" | 10 | 0 | 40° – 53° |
| May | 67° | 41° | 2.0" | 0.3" | 10 | 0 | 48° – 60° |
| June | 73° | 46° | 2.1" | 0.0" | 8 | 0 | 56° – 68° |
| July | 84° | 51° | 0.7" | 0.0" | 3 | 0 | 58° – 73° |
| August | 83° | 50° | 0.6" | 0.0" | 4 | 0 | 60° – 70° |
| September | 73° | 43° | 0.9" | 0.1" | 5 | 0 | 54° – 63° |
| October | 57° | 34° | 1.9" | 0.5" | 10 | 0 | 40° – 52° |
| November | 41° | 27° | 3.0" | 6.1" | 13 | 4 | 27° – 41° |
| December | 33° | 22° | 3.2" | 15.5" | 15 | 15 | 21° – 32° |
| Year | 57° | 35° | 23.3" | 48.2" | 116 | 56 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 20° to 38°. August is the most reliable, staying within 9°.
Where Clayton’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Clayton’s center.
- Snow: Spokane Wfo, WA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Deer Park Airport, 6 miles from the town’s center, 100 ft lower; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Clayton’s climate
What is the weather like in Clayton?
A typical July afternoon reaches 84°, a January night drops to 22°, and about 48 inches of snow falls in a normal winter. Milder January nights than 52% of U.S. towns; cooler July afternoons than 63% of U.S. towns.
How cold does it get in Clayton in winter?
December nights average 22°. About 174 nights a year reach 32° or below and 5 reach 0° or below. In the coldest December of the last 30 years the month averaged 21°.
How much snow does Clayton get?
About 48 inches in a normal winter at Spokane Wfo, WA, most of it in December, with snow on the ground about 56 days a year.
How hot does it get in Clayton?
July, with a typical high of 84° and a low of 51°. About 22 days a year reach 90° and 1 reach 100° (Deer Park Airport).
When is the first and last frost in Clayton?
In half of years the last spring frost (32°) comes by May 22 and the first fall frost by September 14, about 112 frost-free days, at Deer Park Airport.
What growing zone is Clayton in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −5°.
What is the best time of year to visit Clayton?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Clayton getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 52% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Clayton.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.