4 Billion Years On

Arizona Climate – July 2026 Update

Top 5 Cities: Phoenix, Tucson, Mesa, Chandler, and Scottsdale

Arizona climate data from NOAA Climate at a Glance

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At a Glance

Temperature – Average

Arizona
United States
Global
Land + Ocean
Jul
+1.7°C· 4th
28.3°C
+1.8°C· 1st
24.9°C
+1.0°C· 2nd
17.0°C
Record
29.7°C (2023)
24.9°C (2026)
17.0°C (2024)
May–Jul
+2.0°C· 3rd
24.9°C
+1.2°C· 5th
21.0°C
+1.0°C· 2nd
16.5°C
Record
25.1°C (2006)
21.6°C (2018)
16.5°C (2024)
2025
+1.8°C· 2nd
17.2°C
+1.4°C· 4th
12.6°C
+1.0°C· 3rd
15.0°C
Record
17.2°C (2017)
13.1°C (2024)
15.2°C (2024)
Headline: anomaly vs your selected baseline (falls back to the 1961–1990 mean for a column without enough history for it) · Small figure: the actual value · Record = value on record for the ranking above

Climate Map – US

Source: NOAA Climate at a Glance — US states & climate regions (tavg, pcp), plus GPCC (Snow, water-equivalent). Anomalies are vs the 1961–1990 baseline. See methodology.

Typical Climate – Arizona

Köppen BSk · Arid

Arizona has a arid climate (Köppen BSk: Cold steppe), with both a warm/cold cycle and a wet/dry cycle through the year. July is typically the warmest month, averaging 28.1°C, while January is the coldest at 5.9°C. Annual precipitation averages around 279mm, concentrated mostly in the wet season.

Warmest month
Jul 28°C
Coldest month
Jan 6°C
Annual rainfall
193mm
Wettest month
Aug 44mm
Annual snowfall
86mmwater-equiv.
Snowiest month
Jan 18mm
RainSnow (water-equivalent)

Monthly climate normals (20162025) - bar colour and height show average temperature, the shaded area shows average monthly rain, with snow (water-equivalent) shown separately.

Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).

Long-Term Trends

Combined TimelineArizona

Right axis: everything else standardized to standard deviations (σ) from its own average, since mm/hours/days aren't directly comparable to °C or to each other.

MetricTemperature
10-Yr AverageActual Year

Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).

Heatwave Days – Arizona

Warm Spell Duration Index (WSDI) - the WMO/ETCCDI heatwave measure: days in a 6+ day run above the local 90th-percentile temperature for that time of year.

Heatwave Days per Year2020 (Record)10-Yr Avg

Data: World Bank Climate Change Knowledge Portal (ERA5-derived). Refreshed roughly 1-2x/year, ~7-8 months behind present.

Year-on-Year Trends

The 4byo Climate Helix – Arizona

1950202619611990 baselineColdest (1964)20162025 meanWarmest (2017)2026 so far
2026Jul
WetDryJanFebMarAprMayJunJulAugSepOctNovDecWet Start~0 days1950-792016-25Wet End+5 days10°15°20°25°30°
Temp
18.2°C
+2.9 vs base
Precipitation
111mm
-214 vs base
Frost
days
ENSO
RONI 3-mo mean
Playback
8×
Mode
Presets

Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).

Monthly TemperatureArizona

All years since 19642017 (Warmest)1964 (Coldest)2026 (Current Year)

Background lines show the last 40 years (plus the record year and its opposite, wherever they fall).

Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).

Records – Arizona

Latest data Jul 2026
Warmest year
2017
17.2°C
Coldest year
1964
14.3°C
2026 so far
#1/77
18.1°C

NOAA National Centers for Environmental Information (frost: World Bank CCKP; snow: GPCC (DWD)) - Anomalies vs 1901-2000 mean

Shifting Seasons

Warm/cold + wet/dryKöppen BSk · Arid

Arizona has both a clear warm/cold cycle (±11.0°C) and a wet/dry cycle (7× wet:dry ratio). Both sides of the annual rhythm are shown below.

Shifting summer
19 days Longer
Warm Season
1950–1979 Baseline: 27 Apr → 22 Oct · 178 days
2016–2025 Now: 14 Apr → 28 Oct · 197 days
J
F
M
A
M
J
J
A
S
O
N
D
Spr 13 days EarlierAut 6 days Later
Shifting wet season
4 days Longer
Wet Season
1950–1979 Baseline: 14 Aug → 23 Jan · 162 days
2016–2025 Now: 14 Aug → 28 Jan · 167 days
J
F
M
A
M
J
J
A
S
O
N
D
Onset 0 days LaterEnd 5 days Later
-7.1% annual rain
baseline yr·recent yr·ring = global temp anomaly
Wet-season onset
14 Aug14 Aug
0 days Later
When 25% of annual rain has fallen
Wet-season end
23 Jan28 Jan
5 days Later
When 75% of annual rain has fallen
Peak-rain month
AugAug
unchanged
Wet months: 66

Monthly precipitation climatology. A “wet month” exceeds the baseline monthly mean (dashed gold line). Biggest month-to-month shift: Aug (-7 mm, -13%).

Data: NOAA National Centers for Environmental Information (temperature/precipitation; frost: World Bank CCKP; snow: GPCC (DWD)).

Climate Systems

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Emissions & Energy

Explore

Explore Climate Data

Data Sources

Data Sources for Arizona

Every figure on this page is sourced from official, openly published climate datasets. Anomalies are calculated against the 1961–1990 baseline (temperature) and 1991–2020 (rainfall, sunshine, frost) - see the Methodology & Sources page for the complete dataset list and update calendar.

FAQs

FAQs

How is the climate in Arizona changing?

Arizona is warming in line with the rest of the world. The page above shows the latest monthly temperature anomaly versus the 1961-1990 baseline, the long-term annual trend, and the region's rank in the historical record. The headline panel also shows the long-term trend rate per decade and the warmest and coolest years on file.

What is the climate like in Arizona?

Arizona has a arid climate (Köppen BSk: Cold steppe), with both a warm/cold cycle and a wet/dry cycle through the year. July is typically the warmest month, averaging 28.1°C, while January is the coldest at 5.9°C. Annual precipitation averages around 279mm, concentrated mostly in the wet season.

Where does the climate data for Arizona come from?

Climate data for Arizona comes from NOAA Climate at a Glance (temperature and precipitation), refreshed every month, when the upstream temperature and rainfall data are refreshed.

What is the climate baseline used on this page?

Anomalies on this page are calculated against the 1961-1990 climatological baseline, which is the standard reference period used by the Met Office, NOAA, IPCC and most national climate services. Some panels also show the source-native 1901-2000 (NOAA) or 1991-2020 (WMO) baselines for verification. See Methodology & Sources for the full reference.

Which areas does the Arizona climate data cover?

The Arizona climate profile covers Phoenix, Tucson, Mesa, Chandler and surrounding areas. Arizona climate data from NOAA Climate at a Glance

How often is the Arizona climate update refreshed?

The Arizona climate update is refreshed monthly, typically a few days after the previous month closes and the upstream provider (Met Office HadUK-Grid, NOAA Climate at a Glance, Copernicus ERA5 or the Global Carbon Project) publishes its update. See the Climate Rankings for cross-region comparisons.

What counts as a Heatwave Day on the Arizona climate page?

Heatwave Days use the Warm Spell Duration Index (WSDI) - the WMO/ETCCDI-standard heatwave measure: days that are part of a run of 6 or more consecutive days above the local 90th-percentile temperature for that calendar day. The 90th-percentile threshold varies by time of year (a hot day in January is judged differently to one in July) but is fixed to the 1961-1990 baseline for every year shown - it does not shift as the climate warms, which is why Heatwave Days trend upward over time.

Does the Arizona climate page include frost and snow data?

Yes. Frost Days (days with a minimum temperature below 0°C, World Bank CCKP) and snow water-equivalent (GPCC) are shown alongside temperature and precipitation, each measured against the 1961-1990 baseline where a like-for-like historical comparison is available.