weatherbycounty

Pima County Climate

JanFebMarAprMayJunJulAugSepOctNovDec68.1°AVG °F

Avg Annual Temp

68.1°F

Annual Precip

13.4"

Annual Snowfall

0.8"

Extreme Heat Days

139

days >= 90°F/yr

Monthly Temperature

54.4°F avgJFMAMJJASOND

Precipitation Calendar

Dry
Wet= snowfall
1.1"
1.1"
0.8"
0.3"
0.2"
0.3"
2.6"
2.8"
1.4"
0.8"
0.7"
1.2"
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Growing Season & Gardening

USDA Hardiness Zone

9a

Minimum winter temperature range for plant survival

Growing Degree Days

6,865

Excellent for heat-loving crops

Last spring frost (32°F): 02/23
First fall frost (32°F): 12/05

Seasonal Overview

Comfort ZoneSpring59°74°1.4"Summer83°85°5.7"Fall59°80°2.9"Winter51°54°3.4"20°40°60°80°100°

National Comparison

Warmer than 95% of US counties
Wetter than 5% of US counties
More seasonal variation than 12% of US counties

7-Day Outlook

Forecast

Current Conditions

Air Quality

Safety

Weather Alerts

Climate Advisory: Pima County

Climate Verdict

Pima County has a warm, averaging 68.1°F year-round, arid conditions receiving just 13.4 inches of precipitation annually, extreme heat exposure with 139.09999999999997 days per year above 90°F, light snow averaging 0.8 inches per year. This climate profile shapes everything from energy costs to outdoor recreation opportunities.

Seasonal Breakdown

Winters are mild, with January temperatures averaging 51.8°F. summers are hot, with July averaging 85.4°F. The 34°F seasonal variation provides noticeable but manageable change. December is typically the coldest month and July the warmest.

Outdoor & Gardening Guidance

Summer outdoor activities should be planned for early morning or evening to avoid extreme heat.

Regional Context

Pima County is 4.6°F warmer than the Arizona statewide average of 63.5°F, the county experiences 25.68500840825837 more extreme heat days than the state average.

Climate Profile

About Pima County Weather

Deep South Heat in the Sonoran Desert

Pima County’s annual average temperature of 68.1°F far exceeds the national median, reflecting its position in the heart of the Sonoran Desert. Despite the heat, it receives 13.4 inches of rain, which is relatively high for an arid American region.

Consistently Above the State Average

At 68.1°F, Pima County is significantly warmer than the Arizona average of 63.5°F. It remains one of the state's warmer urban hubs, driven by high summer peaks and mild winters.

Moderated by Elevation Compared to Pinal

Pima County is slightly cooler than neighboring Pinal County, which averages 70.1°F annually. However, it receives more rainfall than Yuma County, which sees only a third of Pima's 13.4-inch precipitation total.

Searing Summers and Gentle Winters

Extreme heat defines the local weather, with 139 days per year hitting at least 90°F. July averages a high of 85.4°F, while winters remain exceptionally mild with less than an inch of snow annually.

Manage Intense Sun and Monsoon Rains

Robust air conditioning and sun protection are vital for the 139 days of extreme heat. Residents should also prepare for flash flooding during the summer monsoon season, which contributes significantly to the 13.4 inches of annual rain.

Frequently Asked Questions

What is the average temperature in Pima County?
The average annual temperature in Pima County, AZ is 68.1°F, based on NOAA 30-year climate normals (1991-2020).
How much rain does Pima County get?
Pima County receives an average of 13.4 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 Pima County?
Yes, Pima County receives an average of 0.8 inches of snowfall per year according to NOAA climate normals.
How hot does Pima County get in summer?
The average summer temperature (June-August) in Pima County is 84.1°F. The county experiences an average of 139 days per year above 90°F.
How cold are winters in Pima County?
The average winter temperature (December-February) in Pima County is 52.3°F. January, typically the coldest month, averages 51.8°F.

Track your own weather in Pima 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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