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Union County Climate

JanFebMarAprMayJunJulAugSepOctNovDec52.3°AVG °F

Avg Annual Temp

52.3°F

Annual Precip

40.5"

Annual Snowfall

24.0"

Extreme Heat Days

18

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
2.7"
2.3"
3.0"
3.9"
4.5"
4.8"
4.2"
3.4"
3.2"
2.7"
2.9"
2.9"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

6a

Minimum winter temperature range for plant survival

Growing Degree Days

3,424

Supports most vegetables & fruits

Last spring frost (32°F): 04/19
First fall frost (32°F): 10/26

Seasonal Overview

Comfort ZoneSpring40°63°11.4"Summer71°75°12.4"Fall42°66°8.8"Winter28°33°7.9"20°40°60°80°100°

National Comparison

Warmer than 41% of US counties
Wetter than 47% of US counties
More seasonal variation than 69% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Union County

Climate Verdict

Union County has a mild, with an average annual temperature of 52.3°F, moderately wet with 40.5 inches of annual precipitation, rare extreme heat with only 17.8 days above 90°F annually, moderate snowfall of 24.0 inches annually. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are cold, with January averaging 27.8°F. summers are warm — July averages 74.7°F. The 47°F seasonal variation provides noticeable but manageable change.

Outdoor & Gardening Guidance

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

Regional Context

Union County closely matches the Ohio statewide average temperature of 51.5°F.

Climate Profile

About Union County Weather

Typical Midwestern temperature patterns

Union County’s 52.3°F average temperature is just slightly below the national median. It enjoys a balanced climate with significant seasonal shifts in both temperature and precipitation.

Warmer than the Ohio average

Union County stays warmer than the state average of 51.5°F, recording an average of 52.3°F. It is slightly drier than the rest of the state, receiving 40.5 inches of precipitation.

Warmer than western neighbor Van Wert

Union County is more than a degree warmer than Van Wert County, which averages 51.0°F. It also receives more annual snowfall, recording 24.0 inches compared to Van Wert's 17.1 inches.

Hot summers and moderate winters

The county experiences 18 days of heat over 90°F, contributing to a warm 73.0°F summer average. Winters are cold but manageable, with 24.0 inches of snow and a 30.5°F winter average.

Prepare for variable winter precipitation

Homeowners should prepare for 24.0 inches of snow while ensuring HVAC systems can handle 18 days of extreme heat. Rain gear is also helpful for the 40.5 inches of annual rainfall.

Frequently Asked Questions

What is the average temperature in Union County?
The average annual temperature in Union County, OH is 52.3°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Union County get?
Union County receives an average of 40.5 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 Union County?
Yes, Union County receives an average of 24.0 inches of snowfall per year according to NOAA climate normals.
How hot does Union County get in summer?
The average summer temperature (June-August) in Union County is 73.0°F. The county experiences an average of 18 days per year above 90°F.
How cold are winters in Union County?
The average winter temperature (December-February) in Union County is 30.5°F. January, typically the coldest month, averages 27.8°F.

Track your own weather in Union 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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