Union County Climate
Union County, Oregon
NOAA NCEI 1991-2020 Climate NormalsAvg Annual Temp
48.8°F
Annual Precip
20.6"
Annual Snowfall
12.8"
Extreme Heat Days
30
days >= 90°F/yr
Monthly Temperature
Precipitation Calendar
Growing Season & Gardening
6b
Minimum winter temperature range for plant survival
2,078
Favors cool-season crops
Seasonal Overview
National Comparison
7-Day Outlook
Forecast
Current Conditions
Air Quality
Safety
Weather Alerts
Climate Advisory: Union County
Climate Verdict
Union County has a cool, averaging 48.8°F annually, semi-arid conditions with only 20.6 inches of annual precipitation, occasional hot days — 30.333333333333332 per year above 90°F, light snow averaging 12.8 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 pleasantly cool with July averaging 68.5°F. The 36°F seasonal variation provides noticeable but manageable change. December is typically the coldest month and July the warmest.
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 Oregon statewide average temperature of 50.5°F, it is also noticeably drier, receiving 16.8 inches less precipitation than the state average.
Climate Profile
About Union County Weather
Cooler Temperatures in the Blue Mountains
Union County averages 48.8°F annually, making it cooler than the national median. The region receives a modest 20.6 inches of precipitation, balancing mountain moisture with inland aridity.
Colder and Drier Than State Norms
The county's 48.8°F average falls below the Oregon state average of 50.5°F. It receives roughly 17 inches less precipitation than the state average of 37.4 inches.
Milder Than Wallowa's High Peaks
Union County is about 3 degrees warmer on average than neighboring Wallowa County. While it receives 12.8 inches of snow, it is significantly less than Wallowa's 51-inch average.
Hot July Days and Freezing Winters
The county sees 30 days of extreme heat each year, with July temperatures averaging 68.5°F. Winter is cold, with a January average of 32.1°F and frequent frost.
Prepare for Wide Seasonal Swings
A versatile wardrobe is necessary to handle a 30-day heat season and 12.8 inches of winter snow. Homeowners should ensure pipes are well-insulated against the 32.1°F January average.
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.