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Johnson County Climate

JanFebMarAprMayJunJulAugSepOctNovDec55.1°AVG °F

Avg Annual Temp

55.1°F

Annual Precip

38.7"

Annual Snowfall

13.8"

Extreme Heat Days

37

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
1.1"
1.5"
2.4"
3.9"
5.2"
5.2"
4.4"
4.3"
3.8"
3.1"
2.1"
1.6"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

6b

Minimum winter temperature range for plant survival

Growing Degree Days

4,073

Excellent for heat-loving crops

Last spring frost (32°F): 04/10
First fall frost (32°F): 10/29

Seasonal Overview

Comfort ZoneSpring45°65°11.5"Summer74°79°13.9"Fall44°69°9.1"Winter30°34°4.2"20°40°60°80°100°

National Comparison

Warmer than 52% of US counties
Wetter than 42% of US counties
More seasonal variation than 78% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Johnson County

Climate Verdict

Johnson County has a mild, with an average annual temperature of 55.1°F, moderate rainfall of 38.7 inches per year, occasional hot days — 37.166666666666664 per year above 90°F, light snow averaging 13.8 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are cold, with January averaging 29.7°F. summers are warm — July averages 78.6°F. The 49°F seasonal variation provides noticeable but manageable change.

Outdoor & Gardening Guidance

The moderate temperatures support hiking, cycling, and camping comfortably in spring, summer, and fall.

Regional Context

Johnson County closely matches the Kansas statewide average temperature of 54.8°F, it is also noticeably wetter, receiving 8.4 inches more precipitation than the state average, the county experiences 21.014523809523823 fewer extreme heat days than the state average.

Climate Profile

About Johnson County Weather

Warm Temperate Conditions with High Rainfall

Johnson County averages 55.1°F annually, sitting just above the national median temperature. Its 38.7 inches of annual precipitation is significantly higher than the average for the American West.

Kansas' Wettest Urban Hub

With 38.7 inches of rain, Johnson County is far wetter than the Kansas state average of 30.3 inches. Its annual temperature of 55.1°F is almost perfectly aligned with the state average of 54.8°F.

Consistent with the Kansas City Metro

Johnson shares a similar climate with neighboring Jefferson, but it is the wettest in this group at 38.7 inches. It also has the fewest extreme heat days in this set, averaging only 37 days above 90°F.

Damp Winters and Comfortable Summers

Summers are the most temperate in the region, with a July average of 78.6°F. Winters are chilly but not extreme, averaging 32.5°F with about 13.8 inches of annual snowfall.

Manage Moisture and Moderate Heat

High annual rainfall of 38.7 inches makes basement waterproofing and gutter maintenance essential for homeowners. While heat is moderate, the 37 days above 90°F still require functional cooling systems.

Frequently Asked Questions

What is the average temperature in Johnson County?
The average annual temperature in Johnson County, KS is 55.1°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Johnson County get?
Johnson County receives an average of 38.7 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 Johnson County?
Yes, Johnson County receives an average of 13.8 inches of snowfall per year according to NOAA climate normals.
How hot does Johnson County get in summer?
The average summer temperature (June-August) in Johnson County is 76.7°F. The county experiences an average of 37 days per year above 90°F.
How cold are winters in Johnson County?
The average winter temperature (December-February) in Johnson County is 32.5°F. January, typically the coldest month, averages 29.7°F.

Track your own weather in Johnson 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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