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Clayton County Climate

JanFebMarAprMayJunJulAugSepOctNovDec47.2°AVG °F

Avg Annual Temp

47.2°F

Annual Precip

38.6"

Annual Snowfall

36.8"

Extreme Heat Days

11

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
1.3"
1.3"
2.0"
4.0"
4.8"
6.1"
4.9"
3.7"
3.7"
2.9"
2.2"
1.6"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

5a

Minimum winter temperature range for plant survival

Growing Degree Days

2,829

Supports most vegetables & fruits

Last spring frost (32°F): 05/08
First fall frost (32°F): 10/18

Seasonal Overview

Comfort ZoneSpring35°59°10.8"Summer69°73°14.8"Fall36°63°8.8"Winter18°24°4.2"20°40°60°80°100°

National Comparison

Warmer than 20% of US counties
Wetter than 42% of US counties
More seasonal variation than 92% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Clayton County

Climate Verdict

Clayton County has a cool, averaging 47.2°F annually, moderate rainfall of 38.6 inches per year, rare extreme heat with only 11.05 days above 90°F annually, moderate snowfall of 36.8 inches annually. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are very cold — January averages 17.7°F. summers are warm — July averages 72.5°F. Residents experience a substantial 55°F difference between winter and summer.

Outdoor & Gardening Guidance

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

Regional Context

Clayton County closely matches the Iowa statewide average temperature of 48.0°F, it is somewhat wetter than average for Iowa.

Climate Profile

About Clayton County Weather

Clayton County mirrors the Midwest median

The county's average annual temperature of 47.2°F is standard for the humid continental climate of the northern United States. This temperature is lower than the national average but typical for its latitude.

A wet and temperate Iowa county

Clayton County is slightly cooler than the 48.0°F state average, but it is much wetter than many peers. It receives 38.6 inches of annual precipitation, surpassing the state average of 36.1 inches.

Moderate heat compared to southern Iowa

Clayton County sees only 11 extreme heat days, which is much lower than the 25 days recorded in southern counties like Clarke. Its snowfall of 36.8 inches is fairly typical for northeastern Iowa.

Pleasant summers and standard snowy winters

Summer temperatures average a comfortable 70.6°F, with July peaking at 72.5°F. Winter brings a significant cool down, with a January average of 17.7°F and over 36 inches of snow.

Plan for moisture and moderate winters

With 38.6 inches of precipitation, residents should ensure their homes have proper gutter systems and basement waterproofing. The 36.8 inches of annual snowfall requires standard winter equipment and insulated clothing.

Frequently Asked Questions

What is the average temperature in Clayton County?
The average annual temperature in Clayton County, IA is 47.2°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Clayton County get?
Clayton County receives an average of 38.6 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 Clayton County?
Yes, Clayton County receives an average of 36.8 inches of snowfall per year according to NOAA climate normals.
How hot does Clayton County get in summer?
The average summer temperature (June-August) in Clayton County is 70.6°F. The county experiences an average of 11 days per year above 90°F.
How cold are winters in Clayton County?
The average winter temperature (December-February) in Clayton County is 21.3°F. January, typically the coldest month, averages 17.7°F.

Track your own weather in Clayton 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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