Photo: Marine 69-71 · CC BY-SA 4.0Pima reaches 100° on about 46 days a year, more than all but 168 U.S. towns
A typical July afternoon reaches 100°, a January night drops to 32°, and snow is almost unheard of.
A year in Pima at a glance
Each month’s typical high and low, and what it brings.
What stands out about Pima’s climate
Compared with towns across the U.S., with Pima’s place in Arizona beside it.
What a year in Pima feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 228 frost-free days a year
In half of years the last 32° night comes by March 25 and the first by November 9. Frost and day counts come from NOAA’s station at Safford Ag Ctr, AZ, 11 miles from the town’s center, at about the same height.
The 2023 USDA map puts Pima’s center in zone 8b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 17°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 10 inches of rain a year
August is the wettest month and May the driest. Rain falls on about 49 days a year. Snow is rare: about 0.2" in a normal year at Safford Ag Ctr, AZ, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Pima
49% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55° run from December through February.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Safford Ag Ctr, AZ.
Living with Pima’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
228 frost-free days in zone 8b. The last frost comes by Mar 25 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Nov 9.
Months with highs of 62–84° and lows of 40° or more: March, April and October. 43 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Pima from natural hazards, river flooding is the largest share (51%); heat waves, cold waves, winter storms and ice storms together are 21%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Pima and similar climates
TownRatings has no climate map of the towns around Pima yet.
Climates most like Pima’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Pima, AZ | 32° | 100° | 10" | 0.2" |
| Ivins, UT | 32° | 100° | 11" | 1.2" |
| Monahans, TX | 30° | 98° | 12" | 0.7" |
| Rosamond, CA | 33° | 98° | 8" | 1.2" |
| Summerlin South, NV | 35° | 102° | 5" | 0.2" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Pima averaged 1.3° warmer than the 1900s. The biggest change is in March (+2.2°).
A smaller shift than in 53% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Pima compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Pima’s place among Arizona’s.
Pima weather by month
Highs, lows and precipitation from NOAA’s grid at Pima’s center; snow, wet days and snow on the ground from Safford Ag Ctr, AZ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 62° | 32° | 0.9" | 0.2" | 5 | 0 | 43° – 52° |
| February | 66° | 35° | 0.9" | 0.0" | 4 | 0 | 46° – 57° |
| March | 74° | 41° | 0.5" | 0.0" | 3 | 0 | 50° – 62° |
| April | 82° | 47° | 0.3" | 0.0" | 2 | 0 | 58° – 69° |
| May | 91° | 55° | 0.2" | 0.0" | 2 | 0 | 67° – 77° |
| June | 100° | 65° | 0.2" | 0.0" | 2 | 0 | 77° – 86° |
| July | 100° | 72° | 1.6" | 0.0" | 8 | 0 | 83° – 89° |
| August | 97° | 70° | 1.9" | 0.0" | 8 | 0 | 81° – 90° |
| September | 93° | 63° | 1.2" | 0.0" | 4 | 0 | 74° – 81° |
| October | 84° | 51° | 0.7" | 0.0" | 4 | 0 | 64° – 72° |
| November | 71° | 39° | 0.6" | 0.0" | 3 | 0 | 48° – 63° |
| December | 61° | 32° | 0.9" | 0.0" | 5 | 0 | 43° – 50° |
| Year | 82° | 50° | 9.8" | 0.2" | 49 | 0 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 48° to 63°. July is the most reliable, staying within 6°.
Where Pima’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Pima’s center.
- Snow: Safford Ag Ctr, AZ.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Safford Ag Ctr, AZ, 11 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Pima’s climate
What is the weather like in Pima?
A typical July afternoon reaches 100°, a January night drops to 32°, and snow is almost unheard of. Milder January nights than 75% of U.S. towns; hotter July afternoons than all but 133 U.S. towns.
How cold does it get in Pima in winter?
December nights average 32°. About 70 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 43°.
How much snow does Pima get?
About 0.2 inches in a normal winter at Safford Ag Ctr, AZ, so most winters see none.
How hot does it get in Pima?
July, with a typical high of 100° and a low of 72°. About 142 days a year reach 90° and 46 reach 100° (Safford Ag Ctr, AZ).
When is the first and last frost in Pima?
In half of years the last spring frost (32°) comes by March 25 and the first fall frost by November 9, about 228 frost-free days, at Safford Ag Ctr, AZ.
What growing zone is Pima in?
Zone 8b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 17°.
What is the best time of year to visit Pima?
By one simple rule (highs of 62–84° and lows of 40° or more), March, April and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Pima getting warmer?
Yes: 1991–2020 averaged 1.3° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 53% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Pima.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.