Arivaca Junction reaches 100° on about 22 days a year, more than 96% of U.S. towns
A typical July afternoon reaches 97°, a January night drops to 34°, and snow is almost unheard of.
A year in Arivaca Junction at a glance
Each month’s typical high and low, and what it brings.
What stands out about Arivaca Junction’s climate
Compared with towns across the U.S., with Arivaca Junction’s place in Arizona beside it.
What a year in Arivaca Junction feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 217 frost-free days a year
In half of years the last 32° night comes by April 5 and the first by November 10. Frost and day counts come from NOAA’s station at Tumacacori Nm, AZ, 12 miles from the town’s center, 100 ft higher.
The 2023 USDA map puts Arivaca Junction’s center in zone 9a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 20°. 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 14 inches of rain a year
July is the wettest month and May the driest. Rain falls on about 51 days a year. Snow is rare: about 0.1" in a normal year at Green Valley, AZ, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Arivaca Junction
58% of the work is heating. 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 Tumacacori Nm, AZ.
Living with Arivaca Junction’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
217 frost-free days in zone 9a. The last frost comes by Apr 5 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 10.
Months with highs of 62–84° and lows of 40° or more: March and April.
Parks & trails →Of the yearly building losses FEMA expects in Arivaca Junction from natural hazards, wildfire is the largest share (62%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Arivaca Junction and similar climates
TownRatings has no climate map of the towns around Arivaca Junction yet.
Climates most like Arivaca Junction’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 |
|---|---|---|---|---|
| Arivaca Junction, AZ | 34° | 97° | 14" | 0.1" |
| Valle Vista, CA | 38° | 98° | 12" | 0.0" |
| Monahans, TX | 30° | 98° | 12" | 0.7" |
| Anthony, NM | 31° | 96° | 9" | 0.0" |
| Ivins, UT | 32° | 100° | 11" | 1.2" |
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 Arivaca Junction averaged 1.4° warmer than the 1900s. The biggest change is in March (+2.4°).
A bigger shift than in 52% 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 Arivaca Junction compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Arivaca Junction’s place among Arizona’s.
Arivaca Junction weather by month
Highs, lows and precipitation from NOAA’s grid at Arivaca Junction’s center; snow, wet days and snow on the ground from Green Valley, AZ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 66° | 34° | 0.8" | 0.0" | 4 | 0 | 45° – 55° |
| February | 69° | 36° | 1.0" | 0.0" | 4 | 0 | 47° – 58° |
| March | 75° | 41° | 0.6" | 0.1" | 3 | 0 | 52° – 63° |
| April | 81° | 45° | 0.4" | 0.0" | 2 | 0 | 58° – 67° |
| May | 90° | 52° | 0.1" | 0.0" | 1 | 0 | 65° – 76° |
| June | 99° | 62° | 0.3" | 0.0" | 2 | 0 | 76° – 84° |
| July | 97° | 69° | 3.2" | 0.0" | 10 | 0 | 81° – 86° |
| August | 95° | 68° | 3.1" | 0.0" | 10 | 0 | 79° – 86° |
| September | 93° | 62° | 1.9" | 0.0" | 5 | 0 | 74° – 79° |
| October | 85° | 50° | 0.7" | 0.0" | 3 | 0 | 64° – 71° |
| November | 75° | 40° | 0.6" | 0.0" | 2 | 0 | 49° – 64° |
| December | 65° | 33° | 1.2" | 0.0" | 4 | 0 | 45° – 54° |
| Year | 82° | 49° | 14.0" | 0.1" | 51 | 0 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 49° to 64°. July is the most reliable, staying within 5°.
Where Arivaca Junction’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 Arivaca Junction’s center.
- Snow: Green Valley, AZ.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Tumacacori Nm, AZ, 12 miles from the town’s center, 100 ft higher; 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 Arivaca Junction’s climate
What is the weather like in Arivaca Junction?
A typical July afternoon reaches 97°, a January night drops to 34°, and snow is almost unheard of. Milder January nights than 78% of U.S. towns; hotter July afternoons than 98% of U.S. towns.
How cold does it get in Arivaca Junction in winter?
December nights average 33°. About 60 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 45°.
How much snow does Arivaca Junction get?
About 0.1 inches in a normal winter at Green Valley, AZ, so most winters see none.
How hot does it get in Arivaca Junction?
July, with a typical high of 97° and a low of 69°. About 115 days a year reach 90° and 22 reach 100° (Tumacacori Nm, AZ).
When is the first and last frost in Arivaca Junction?
In half of years the last spring frost (32°) comes by April 5 and the first fall frost by November 10, about 217 frost-free days, at Tumacacori Nm, AZ.
What growing zone is Arivaca Junction in?
Zone 9a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 20°.
What is the best time of year to visit Arivaca Junction?
By one simple rule (highs of 62–84° and lows of 40° or more), March and April. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Arivaca Junction getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 52% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Arivaca Junction.
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.