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Cowlitz County Climate

Cowlitz County, Washington

NOAA NCEI 1991-2020 Climate Normals
JanFebMarAprMayJunJulAugSepOctNovDec53.2°AVG °F

Avg Annual Temp

53.2°F

Annual Precip

61.4"

Annual Snowfall

3.0"

Extreme Heat Days

10

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
8.6"
6.4"
6.7"
5.2"
3.5"
2.5"
0.7"
1.0"
2.6"
5.6"
9.1"
9.5"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

8b

Minimum winter temperature range for plant survival

Growing Degree Days

2,268

Favors cool-season crops

Last spring frost (32°F): 04/08
First fall frost (32°F): 11/05

Seasonal Overview

Comfort ZoneSpring47°57°15.5"Summer61°67°4.1"Fall46°63°17.3"Winter41°43°24.4"20°40°60°80°100°

National Comparison

Warmer than 44% of US counties
Wetter than 96% of US counties
More seasonal variation than 3% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Cowlitz County

Climate Verdict

Cowlitz County has a mild, with an average annual temperature of 53.2°F, very wet conditions receiving 61.4 inches of precipitation annually, rare extreme heat with only 9.5 days above 90°F annually, light snow averaging 3.0 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are mild, with January temperatures averaging 41.4°F. summers are pleasantly cool with July averaging 66.4°F. The climate is remarkably stable year-round, with only a 25°F difference between January and July. December is typically the coldest month and August the warmest.

Outdoor & Gardening Guidance

Growing season and gardening data is currently limited for Cowlitz County. Check the USDA Plant Hardiness Zone Map and local extension office for specific guidance.

Regional Context

Cowlitz County is 3.3°F warmer than the Washington statewide average of 49.9°F, it is also noticeably wetter, receiving 22.9 inches more precipitation than the state average.

Climate Profile

About Cowlitz County Weather

A warm and exceptionally wet county

Cowlitz County's 53.2°F average temperature is near the national median. Its 61.4 inches of annual precipitation makes it one of the wettest regions in the country.

One of Washington's wettest, warmest areas

The county is significantly warmer and wetter than the state averages of 49.9°F and 38.5 inches. It ranks high for total annual rainfall in Washington.

Wetter than Clark and Clallam counties

With 61.4 inches of rain, Cowlitz outpaces both Clark (44 inches) and Clallam (58.7 inches). It maintains a mild temperature that mirrors its southern neighbors.

Mild winters and damp, cool summers

Summer averages 64.8°F with 10 days of heat over 90°F. Winter is notably mild at 41.8°F, seeing only 3.0 inches of snow despite heavy overall precipitation.

Focus on moisture and mold prevention

Dehumidifiers and waterproof home coatings are essential for managing 61.4 inches of rain. Outdoor gear should prioritize breathability to handle the mild but constant dampness.

Frequently Asked Questions

What is the average temperature in Cowlitz County?
The average annual temperature in Cowlitz County, WA is 53.2°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Cowlitz County get?
Cowlitz County receives an average of 61.4 inches of precipitation per year, including both rain and meltwater from snow. This is based on NOAA 30-year climate normals.
Does it snow in Cowlitz County?
Yes, Cowlitz County receives an average of 3.0 inches of snowfall per year according to NOAA climate normals.
How hot does Cowlitz County get in summer?
The average summer temperature (June-August) in Cowlitz County is 64.8°F. The county experiences an average of 10 days per year above 90°F.
How cold are winters in Cowlitz County?
The average winter temperature (December-February) in Cowlitz County is 41.8°F. January, typically the coldest month, averages 41.4°F.

Track your own weather in Cowlitz County

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Data sources: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991-2020. Forecast and alert data from National Weather Service API. Air quality data from Open-Meteo.

Climate normals are 30-year averages of weather variables. Station data is aggregated to county level. Forecasts and alerts are fetched live and may change frequently. Data is informational only — not a substitute for official National Weather Service forecasts or emergency weather warnings.

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor
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