Twin Falls climate — normals and trends
Twin Falls (United States) has a cold semi-arid climate (BSk) under the Köppen-Geiger classification. Its mean annual temperature is 10.2 °C and it receives 340 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 (24.4 °C on average) and the coldest is January (-2.3 °C). Rainfall peaks in December.
Twin Falls averages 122 frost days, 65 hot days (≥ 30 °C) and 79 rainy days per year.
Twin Falls has warmed by +2.6 °C between 1940 and 2025, or +0.31 °C per decade. This trend is statistically significant.
The number of frost days there went from about 139 to 105 per year over the period.
The hottest day of the period reached 42.2 °C (on 12 July 2002) and the coldest -31.2 °C (on 11 December 1972).
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
Twin FallsIdaho
- coords
- 42.56°, -114.46°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.2°C
Average daily high
16.8°C
Average daily low
3.9°C
Annual rainfall
340mm
Sunshine / day
10.5h
Mean relative humidity
51%
Average peak wind
17.5km/h
Seasonal range
26.7°C
Frost days (< 0 °C)
122 d/yr
Hot days (≥ 30 °C)
65 d/yr
Rainy days (≥ 1 mm)
79 d/yr
Annual snowfall
65.1 cm
Average feels-like high
13.6 °C
Average feels-like low
0.0 °C
Average peak gust
36.3 km/h
Tropical nights (≥ 20 °C)
5 d/yr
Solar radiation
17.8 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+2.6 °C
since 1940
+0.3 °C per decade · r² = 0.42 · 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
42.2 °C
12 July 2002
Coldest day
-31.2 °C
11 December 1972
Wettest day
35 mm
5 August 2014
Windiest day
48.2 km/h
30 August 1999
Strongest gust
97.9 km/h
17 March 2014
Hottest feels-like
41.7 °C
17 July 1998
Coldest feels-like
-36.6 °C
11 December 1972
Snowiest day
15.3 cm
23 November 2023
Sunniest day
14.9 h
18 June 2025
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 | 3.4 °C | +1.0 °C | 20 mm | -20 mm |
| Feb | 6.6 °C | +0.7 °C | 72 mm | +38 mm |
| Mar | 12.9 °C | +2.3 °C | 38 mm | -2 mm |
| Apr | 18.3 °C | +2.6 °C | 10 mm | -25 mm |
| May | 23.9 °C | +2.8 °C | 22 mm | -14 mm |
| Jun | 29.2 °C | +2.6 °C | 1 mm | -21 mm |
| Jul | 33.2 °C | +0.5 °C | 2 mm | -5 mm |
| Aug | 31.4 °C | +0.1 °C | 24 mm | +13 mm |
| Sep | 27.9 °C | +2.4 °C | 8 mm | -8 mm |
| Oct | 17.1 °C | -0.8 °C | 32 mm | +9 mm |
| Nov | 13.8 °C | +4.8 °C | 5 mm | -31 mm |
| Dec | 10.7 °C | +7.3 °C | 46 mm | +5 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 Twin Falls?
Twin Falls has a cold semi-arid climate (Köppen BSk). Over 1940-2025, the average annual temperature is 10.2 °C and it receives 340 mm of precipitation per year.
What is the hottest day ever recorded in Twin Falls?
The hottest day measured in Twin Falls between 1940 and 2025 was 12 July 2002, reaching 42.2 °C.
What is the coldest day in Twin Falls?
The coldest day measured in Twin Falls between 1940 and 2025 was 11 December 1972, at -31.2 °C.
Does it snow in Twin Falls?
Yes. Twin Falls gets on average 65.1 cm of snow per year and has around 122 frost days.
Has the climate of Twin Falls warmed?
Yes: Twin Falls warmed by +2.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Twin Falls?
The wettest day measured in Twin Falls between 1940 and 2025 was 5 August 2014, with 35 mm of rain in 24 hours.
What was the windiest day in Twin Falls?
The windiest day measured in Twin Falls between 1940 and 2025 was 30 August 1999, with winds reaching 48.2 km/h.
What is the warmest month in Twin Falls?
The warmest month in Twin Falls is July (24.4 °C on average); the coldest is January (-2.3 °C).
How much does it rain in Twin Falls?
Twin Falls receives on average 340 mm of precipitation per year, spread over about 79 rainy days.
Is it sunny in Twin Falls?
Twin Falls gets on average 10.5 hours of sunshine per day, roughly 3,833 hours per year over 1940-2025.
What is the biggest single-day snowfall in Twin Falls?
The heaviest 24-hour snowfall measured in Twin Falls between 1940 and 2025 was 23 November 2023, with 15.3 cm.
Are there tropical nights in Twin Falls?
Yes: Twin Falls has on average 5 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Twin Falls?
In Twin Falls, between 1940 and 2025, the highest apparent temperature reached 41.7 °C on 17 July 1998, and the lowest was -36.6 °C on 11 December 1972.
Compare Twin Falls with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Twin Falls