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Jefferson County Climate

Jefferson County, Kentucky

NOAA NCEI 1991-2020 Climate Normals
JanFebMarAprMayJunJulAugSepOctNovDec57.9°AVG °F

Avg Annual Temp

57.9°F

Annual Precip

49.4"

Annual Snowfall

10.9"

Extreme Heat Days

39

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
3.5"
3.5"
4.7"
4.9"
5.2"
4.6"
4.2"
3.5"
3.8"
3.8"
3.6"
4.3"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

7a

Minimum winter temperature range for plant survival

Growing Degree Days

4,516

Excellent for heat-loving crops

Last spring frost (32°F): 04/03
First fall frost (32°F): 11/07

Seasonal Overview

Comfort ZoneSpring47°67°14.8"Summer75°79°12.2"Fall48°71°11.1"Winter35°39°11.2"20°40°60°80°100°

National Comparison

Warmer than 63% of US counties
Wetter than 73% of US counties
More seasonal variation than 55% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Jefferson County

Climate Verdict

Jefferson County has a mild, with an average annual temperature of 57.9°F, moderately wet with 49.4 inches of annual precipitation, occasional hot days — 39.2 per year above 90°F, light snow averaging 10.9 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are cold, with January averaging 34.9°F. summers are warm — July averages 78.8°F. The 44°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

Jefferson County closely matches the Kentucky statewide average temperature of 56.0°F.

Climate Profile

About Jefferson County Weather

A warm, humid urban climate

Jefferson County's annual average temperature of 57.9°F is notably warmer than the national median. The humid subtropical environment is often influenced by an urban heat island effect within the Louisville metro area.

Warm and wet relative to Kentucky

The county is warmer than the state average of 56.2°F, though its 49.4 inches of rain falls just below the state average. This makes it a relatively warm hub within the Commonwealth.

Snowier than its western neighbors

Jefferson County receives 10.9 inches of annual snowfall, which is significantly higher than Henderson County's 6.5 inches. Its temperature profile is also slightly cooler than the extreme heat found in Hopkins County.

Hot summers and snowy spells

July brings an average of 78.8°F and contributes to 39 days of extreme heat per year. Winter features a January average of 34.9°F and the highest snowfall on this list at 10.9 inches.

Winter prep and summer cooling

A sturdy snow shovel and salt are necessary for the nearly 11 inches of annual snow. High electricity bills are likely in July when 39 days of heat over 90°F stress local power grids.

Frequently Asked Questions

What is the average temperature in Jefferson County?
The average annual temperature in Jefferson County, KY is 57.9°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Jefferson County get?
Jefferson County receives an average of 49.4 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 Jefferson County?
Yes, Jefferson County receives an average of 10.9 inches of snowfall per year according to NOAA climate normals.
How hot does Jefferson County get in summer?
The average summer temperature (June-August) in Jefferson County is 77.4°F. The county experiences an average of 39 days per year above 90°F.
How cold are winters in Jefferson County?
The average winter temperature (December-February) in Jefferson County is 37.5°F. January, typically the coldest month, averages 34.9°F.

Track your own weather in Jefferson 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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