Photo: DPPed · CC BY-SA 3.0Phoenix reaches 100° on about 111 days a year, more than all but 56 U.S. towns
A typical July afternoon reaches 105°, a January night drops to 42°, and snow is almost unheard of.
A year in Phoenix at a glance
Each month’s typical high and low, and what it brings.
What stands out about Phoenix’s climate
Compared with towns across the U.S., with Phoenix’s place in Arizona beside it.
What a year in Phoenix feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 331 frost-free days a year
In half of years the last 32° night comes by January 20 and the first by December 15. Day counts come from NOAA’s station at Sky Harbor, 11 miles from the city’s center point, 250 ft lower; frost dates and degree days from Youngtown, AZ, 12 miles away.
The 2023 USDA map puts Phoenix’s center in zone 9b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 30°. Plant labels use the zone; frost dates tell you when to plant.
90° days by month
Average days at 90° or more
About 8 inches of rain a year
February is the wettest month and June the driest. Rain falls on about 23 days a year. Snow is rare: about 0.2" in a normal year at Tolleson 1 E, AZ, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Phoenix
26% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55°: December and January.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Youngtown, AZ.
Living with Phoenix’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
331 frost-free days in zone 9b. The last frost comes by Jan 20 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Dec 15.
Months with highs of 62–84° and lows of 40° or more: January, February, March, November and December. 847 miles of trails are waiting.
Parks & trails →Heat waves are 49% of the yearly building losses FEMA expects in Phoenix from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Phoenix and its neighbors
Tempe has the coldest January nights next door (41°, 1° colder) and Maricopa Colony the hottest July afternoons (106°, 1° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Phoenix’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 |
|---|---|---|---|---|
| Phoenix, AZ | 42° | 105° | 8" | 0.2" |
| Desert Hot Springs, CA | 42° | 105° | 7" | 0.8" |
| Henderson, NV | 40° | 105° | 5" | 0.2" |
| St. George, UT | 33° | 103° | 8" | 1.2" |
| Laredo, TX | 45° | 99° | 20" | 0.1" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Phoenix averaged 2.3° warmer than the 1900s. The biggest change is in March (+3.1°).
A bigger shift than in 98% 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. In a city of 1.7 million, part of the change is the city itself: pavement and buildings hold heat (the urban heat island).
How Phoenix compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Phoenix’s place among Arizona’s.
Phoenix weather by month
Highs, lows and precipitation from NOAA’s grid at Phoenix’s center; snow, wet days and snow on the ground from Tolleson 1 E, AZ. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 67° | 42° | 0.9" | 0.1" | 3 | 0 | 51° – 60° |
| February | 71° | 45° | 1.1" | 0.1" | 3 | 0 | 52° – 63° |
| March | 78° | 49° | 1.0" | 0.0" | 3 | 0 | 56° – 70° |
| April | 85° | 55° | 0.2" | 0.0" | 1 | 0 | 64° – 75° |
| May | 94° | 63° | 0.1" | 0.0" | 1 | 0 | 73° – 83° |
| June | 103° | 72° | 0.0" | 0.0" | 0 | 0 | 82° – 91° |
| July | 105° | 80° | 0.8" | 0.0" | 3 | 0 | 89° – 96° |
| August | 104° | 79° | 1.0" | 0.0" | 3 | 0 | 88° – 96° |
| September | 99° | 73° | 0.6" | 0.0" | 2 | 0 | 82° – 88° |
| October | 88° | 60° | 0.5" | 0.0" | 1 | 0 | 71° – 79° |
| November | 76° | 48° | 0.6" | 0.0" | 2 | 0 | 54° – 68° |
| December | 66° | 41° | 0.9" | 0.0" | 3 | 0 | 51° – 57° |
| Year | 86° | 59° | 7.9" | 0.2" | 23 | 0 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 54° to 68°. July is the most reliable, staying within 6°.
Where Phoenix’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 Phoenix’s center.
- Snow: Tolleson 1 E, AZ.
- Frost dates, heating and cooling: Youngtown, AZ, 12 miles away.
- Freezing nights, 90° and 100° days: Sky Harbor, 11 miles from the city’s center point, 250 ft lower; the city’s official station.
- 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 Phoenix’s climate
What is the weather like in Phoenix?
A typical July afternoon reaches 105°, a January night drops to 42°, and snow is almost unheard of. Milder January nights than 91% of U.S. towns; hotter July afternoons than all but 59 U.S. towns.
How cold does it get in Phoenix in winter?
December nights average 41°. A night at 32° or below comes in only some winters (0.6 a year on average). In the coldest December of the last 30 years the month averaged 51°.
How much snow does Phoenix get?
About 0.2 inches in a normal winter at Tolleson 1 E, AZ, so most winters see none.
How hot does it get in Phoenix?
July, with a typical high of 105° and a low of 80°. About 173 days a year reach 90° and 111 reach 100° (Youngtown, AZ).
When is the first and last frost in Phoenix?
In half of years the last spring frost (32°) comes by January 20 and the first fall frost by December 15, about 331 frost-free days, at Youngtown, AZ.
What growing zone is Phoenix in?
Zone 9b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 30°.
What is the best time of year to visit Phoenix?
By one simple rule (highs of 62–84° and lows of 40° or more), January, February, March, November and December. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Phoenix getting warmer?
Yes: 1991–2020 averaged 2.3° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 98% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Phoenix.
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.