Montgomery County Climate
Montgomery County, Illinois
NOAA NCEI 1991-2020 Climate NormalsAvg Annual Temp
55.5°F
Annual Precip
42.1"
Annual Snowfall
—
Extreme Heat Days
42
days >= 90°F/yr
Monthly Temperature
Precipitation Calendar
Growing Season & Gardening
6b
Minimum winter temperature range for plant survival
4,156
Excellent for heat-loving crops
Seasonal Overview
National Comparison
7-Day Outlook
Forecast
Current Conditions
Air Quality
Safety
Weather Alerts
Climate Advisory: Montgomery County
Climate Verdict
Montgomery County has a mild, with an average annual temperature of 55.5°F, moderately wet with 42.1 inches of annual precipitation, occasional hot days — 42.4 per year above 90°F. This climate profile shapes everything from energy costs to outdoor recreation opportunities.
Seasonal Breakdown
Winters are cold, with January averaging 29.9°F. summers are warm — July averages 77.6°F. The 48°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
Montgomery County closely matches the Illinois statewide average temperature of 52.8°F, the county experiences 15.138967803030301 more extreme heat days than the state average.
Climate Profile
About Montgomery County Weather
Warmer and WETTER than Average
Montgomery’s average annual temperature of 55.5°F sits above the national median for temperate zones. It pairs this warmth with 42.1 inches of precipitation, creating a lush but humid environment.
Warmer Than Most of Illinois
At 55.5°F, the county is notably warmer than the Illinois state average of 52.8°F. This temperature gap reflects its position in the warmer southern-central tier of the state.
Higher Heat Than Nearby Morgan
Montgomery experiences 42 days of extreme heat annually, significantly more than the 32 days recorded in Morgan County to the northwest. It serves as a transition point into the hotter southern Illinois climate.
Intense Summers and Mild Winters
July brings an average of 77.6°F and contributes to 42 days per year where temperatures exceed 90°F. Winters stay relatively mild with a January average of 29.9°F and a winter mean of 33.1°F.
Prepare for Prolonged Heat Waves
With 42 days of extreme heat annually, high-efficiency air conditioning and adequate insulation are essential for comfort. Residents should also plan outdoor activities around the high humidity of the 42.1-inch rain cycle.
Frequently Asked Questions
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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.