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Perry County Climate

JanFebMarAprMayJunJulAugSepOctNovDec56.0°AVG °F

Avg Annual Temp

56.0°F

Annual Precip

47.2"

Annual Snowfall

10.3"

Extreme Heat Days

38

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
3.1"
2.8"
4.3"
5.0"
5.6"
4.7"
4.4"
3.2"
3.3"
3.5"
4.0"
3.2"
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

4,113

Excellent for heat-loving crops

Last spring frost (32°F): 04/06
First fall frost (32°F): 10/22

Seasonal Overview

Comfort ZoneSpring46°66°14.9"Summer74°77°12.3"Fall45°68°10.9"Winter32°37°9.1"20°40°60°80°100°

National Comparison

Warmer than 56% of US counties
Wetter than 66% of US counties
More seasonal variation than 62% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Perry County

Climate Verdict

Perry County has a mild, with an average annual temperature of 56.0°F, moderately wet with 47.2 inches of annual precipitation, occasional hot days — 37.8 per year above 90°F, light snow averaging 10.3 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are cold, with January averaging 32.1°F. summers are warm — July averages 77.4°F. The 45°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

Perry County is 3.2°F warmer than the Illinois statewide average of 52.8°F, it is also noticeably wetter, receiving 5.4 inches more precipitation than the state average.

Climate Profile

About Perry County Weather

A Warm and Wet Southern Profile

Perry County is warmer and wetter than most of the country, with a 56.0°F annual average and 47.2 inches of rain. This climate supports dense vegetation and long, humid summers.

Hotter and Wetter Than Illinois Norms

At 56.0°F, Perry is 3.2 degrees warmer than the Illinois state average. It also receives 5.5 inches more precipitation than the average Illinois county.

Much Rainier Than Central Neighbors

Perry receives 47.2 inches of rain, dwarfing the 38.1 inches seen in Peoria County. It also sees 15 more extreme heat days than its neighbors to the north.

Long Summers and Short Winters

July averages 77.4°F with 38 days of extreme heat annually. Winters are mild, averaging 35.0°F with just 10.3 inches of snow, allowing for more outdoor activity year-round.

Prioritize Humidity and Flood Control

With 47.2 inches of rain, sump pumps and dehumidifiers are essential for every home. High-capacity cooling is a must for the 38 days of heat exceeding 90°F.

Frequently Asked Questions

What is the average temperature in Perry County?
The average annual temperature in Perry County, IL is 56.0°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Perry County get?
Perry County receives an average of 47.2 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 Perry County?
Yes, Perry County receives an average of 10.3 inches of snowfall per year according to NOAA climate normals.
How hot does Perry County get in summer?
The average summer temperature (June-August) in Perry County is 75.8°F. The county experiences an average of 38 days per year above 90°F.
How cold are winters in Perry County?
The average winter temperature (December-February) in Perry County is 35.0°F. January, typically the coldest month, averages 32.1°F.

Track your own weather in Perry 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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