Green Valley climate — normals and trends
Green Valley (United States) has a hot semi-arid climate (BSh) under the Köppen-Geiger classification. Its mean annual temperature is 18.3 °C and it receives 303 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (27.5 °C on average) and the coldest is January (8.8 °C). Rainfall peaks in August.
Green Valley averages 17 frost days, 125 hot days (≥ 30 °C) and 56 rainy days per year.
Green Valley has warmed by +2.6 °C between 1940 and 2025, or +0.30 °C per decade. This trend is statistically significant.
The number of frost days there went from about 27 to 7 per year over the period.
The hottest day of the period reached 42.9 °C (on 19 June 2016) and the coldest -14.7 °C (on 26 December 1987).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
Green ValleyArizona
- coords
- 31.85°, -110.99°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
18.3°C
Average daily high
25.3°C
Average daily low
11.6°C
Annual rainfall
303mm
Sunshine / day
11.2h
Mean relative humidity
40%
Average peak wind
16.9km/h
Seasonal range
18.7°C
Frost days (< 0 °C)
17 d/yr
Hot days (≥ 30 °C)
125 d/yr
Rainy days (≥ 1 mm)
56 d/yr
Annual snowfall
4.1 cm
Average feels-like high
22.8 °C
Average feels-like low
9.1 °C
Average peak gust
36.7 km/h
Tropical nights (≥ 20 °C)
65 d/yr
Solar radiation
21.4 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.6 °C
since 1940
+0.3 °C per decade · r² = 0.65 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
42.9 °C
19 June 2016
Coldest day
-14.7 °C
26 December 1987
Wettest day
69 mm
8 October 2014
Windiest day
50.9 km/h
10 December 1949
Strongest gust
116.6 km/h
22 January 2010
Hottest feels-like
43.2 °C
22 July 2023
Coldest feels-like
-20.1 °C
26 December 1987
Snowiest day
11.4 cm
25 February 1987
Sunniest day
13.8 h
18 June 1955
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 16.2 °C | +0.1 °C | 5 mm | -20 mm |
| Feb | 22.7 °C | +4.9 °C | 2 mm | -19 mm |
| Mar | 22.2 °C | +1.8 °C | 19 mm | -1 mm |
| Apr | 25.8 °C | +1.1 °C | 2 mm | -6 mm |
| May | 30.2 °C | +0.8 °C | 3 mm | -2 mm |
| Jun | 36.2 °C | +1.8 °C | 18 mm | +11 mm |
| Jul | 34.7 °C | +1.0 °C | 79 mm | +19 mm |
| Aug | 35.6 °C | +3.4 °C | 27 mm | -37 mm |
| Sep | 32.3 °C | +1.2 °C | 34 mm | +3 mm |
| Oct | 28.6 °C | +2.0 °C | 45 mm | +26 mm |
| Nov | 23.6 °C | +2.9 °C | 30 mm | +15 mm |
| Dec | 22.3 °C | +5.7 °C | 7 mm | -21 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Green Valley?
Green Valley has a hot semi-arid climate (Köppen BSh). Over 1940-2025, the average annual temperature is 18.3 °C and it receives 303 mm of precipitation per year.
What is the hottest day ever recorded in Green Valley?
The hottest day measured in Green Valley between 1940 and 2025 was 19 June 2016, reaching 42.9 °C.
What is the coldest day in Green Valley?
The coldest day measured in Green Valley between 1940 and 2025 was 26 December 1987, at -14.7 °C.
Does it snow in Green Valley?
Yes. Green Valley gets on average 4.1 cm of snow per year and has around 17 frost days.
Has the climate of Green Valley warmed?
Yes: Green Valley warmed by +2.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Green Valley?
The wettest day measured in Green Valley between 1940 and 2025 was 8 October 2014, with 69 mm of rain in 24 hours.
What was the windiest day in Green Valley?
The windiest day measured in Green Valley between 1940 and 2025 was 10 December 1949, with winds reaching 50.9 km/h.
What is the warmest month in Green Valley?
The warmest month in Green Valley is July (27.5 °C on average); the coldest is January (8.8 °C).
How much does it rain in Green Valley?
Green Valley receives on average 303 mm of precipitation per year, spread over about 56 rainy days.
Is it sunny in Green Valley?
Green Valley gets on average 11.2 hours of sunshine per day, roughly 4,088 hours per year over 1940-2025.
What is the biggest single-day snowfall in Green Valley?
The heaviest 24-hour snowfall measured in Green Valley between 1940 and 2025 was 25 February 1987, with 11.4 cm.
Are there tropical nights in Green Valley?
Yes: Green Valley has on average 65 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Green Valley?
In Green Valley, between 1940 and 2025, the highest apparent temperature reached 43.2 °C on 22 July 2023, and the lowest was -20.1 °C on 26 December 1987.
Compare Green Valley with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Green Valley