weatherbycounty

Brown County Climate

JanFebMarAprMayJunJulAugSepOctNovDec53.9°AVG °F

Avg Annual Temp

53.9°F

Annual Precip

39.4"

Annual Snowfall

13.5"

Extreme Heat Days

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
1.8"
1.9"
2.7"
4.2"
5.0"
4.6"
3.5"
3.8"
3.5"
3.4"
2.6"
2.4"
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

Seasonal Overview

Comfort ZoneSpring42°64°11.8"Summer73°77°11.8"Fall43°68°9.6"Winter28°33°6.1"20°40°60°80°100°

National Comparison

Warmer than 47% of US counties
Wetter than 44% of US counties
More seasonal variation than 80% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Brown County

Climate Verdict

Climate data for Brown County is currently being compiled from NOAA sources. Check back soon for detailed weather normals.

Seasonal Breakdown

Seasonal weather data for this county is based on regional climate patterns. Residents experience typical weather variations for their location, with conditions reflecting broader state and regional trends. Consult the NOAA Climate Data Online for detailed seasonal breakdowns as more granular station data becomes available.

Outdoor & Gardening Guidance

Growing season and gardening guidance for Brown County will be added as data becomes available.

Regional Context

Comparative climate data for Brown County is being processed.

Climate Profile

About Brown County Weather

Moderate Rainfall and Typical Seasons

Brown County averages 39.4 inches of precipitation annually, placing it slightly below the national median. This level of moisture supports a standard continental climate with four distinct seasonal transitions.

Drier than the Illinois Average

The county receives 39.4 inches of rain, which is about 2.3 inches less than the Illinois state average. Its 13.5 inches of annual snow is also significantly lower than the northern state average.

Milder Winters than Bureau County

Brown County's 13.5 inches of snow is much more manageable than the 32.2 inches recorded in Bureau County. It enjoys a drier profile overall, with precipitation staying under 40 inches annually.

Light Snow and Regular Rainfall

The 13.5 inches of annual snow makes for relatively mild winters compared to the state's northern tier. Without local temperature data, residents rely on the 39.4 inches of annual precipitation for seasonal agricultural planning.

Standard Midwest Seasonal Prep

Prepare for moderate winters with basic snow clearing tools for the 13.5 inches of expected snowfall. Summer gardens may require supplemental watering since the 39.4 inches of rain falls below the state average.

Frequently Asked Questions

What is the average temperature in Brown County?
The average annual temperature in Brown County, IL is 53.9°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Brown County get?
Brown County receives an average of 39.4 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 Brown County?
Yes, Brown County receives an average of 13.5 inches of snowfall per year according to NOAA climate normals.
How hot does Brown County get in summer?
The average summer temperature (June-August) in Brown County is 75.3°F.
How cold are winters in Brown County?
The average winter temperature (December-February) in Brown County is 30.6°F. January, typically the coldest month, averages 27.5°F.

Track your own weather in Brown County

Ambient Weather personal weather stations give you hyperlocal climate data.

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Data sources: ERA5 Reanalysis (modeled) via Open-Meteo (gap-filled where station data unavailable).. 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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