Cottonwood, Idaho climate: Normal weather by month, frost dates and records
Cottonwood's normal year runs from 24°F December nights to 81°F August afternoons, with 22.6 inches of precipitation and 61 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.7°C, December lows of −5°C, August highs of 27°C, 575 mm of precipitation a year.
- NOAA stationCottonwood (2 mi WSW)
- Station IDUSC00102159
- Location46.03°N 116.39°W
- Elevation3,945 ft (1,202 m)
- Population921
On October 23, the normal high in Cottonwood is 54°F and the normal low 36°F, and the chance of measurable rain or snow is 37%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Cottonwood.
- Jan 37° 25°
- Feb 40° 26°
- Mar 48° 31°
- Apr 54° 35°
- May 63° 42°
- Jun 69° 48°
- Jul 81° 56°
- Aug 81° 56°
- Sep 72° 49°
- Oct 57° 39°
- Nov 44° 30°
- Dec 36° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Cottonwood each month?
August is the warmest month, with normal highs of 81°F; December the coldest, with normal lows of 24°F. The most precipitation falls in May (2.78 in), the least in August (0.84 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 37°F | 25°F | 30.9°F | 1.81 | 16.3 | 13 | <1 | 27 | 9 h |
| February | 40°F | 26°F | 33.3°F | 1.64 | 11.0 | 11 | <1 | 22 | 10 h 20 min |
| March | 48°F | 31°F | 39.0°F | 2.12 | 8.7 | 13 | <1 | 19 | 11 h 50 min |
| April | 54°F | 35°F | 44.5°F | 2.67 | 1.8 | 15 | <1 | 11 | 13 h 30 min |
| May | 63°F | 42°F | 52.6°F | 2.78 | 0.3 | 15 | <1 | 3 | 14 h 50 min |
| June | 69°F | 48°F | 58.7°F | 2.64 | 0.0 | 12 | <1 | <1 | 15 h 40 min |
| July | 81°F | 56°F | 68.3°F | 1.16 | 0.0 | 6 | 4 | <1 | 15 h 30 min |
| August | 81°F | 56°F | 68.6°F | 0.84 | 0.0 | 5 | 4 | <1 | 14 h 10 min |
| September | 72°F | 49°F | 60.4°F | 1.06 | 0.1 | 6 | 1 | <1 | 12 h 40 min |
| October | 57°F | 39°F | 48.0°F | 1.77 | 0.4 | 11 | <1 | 6 | 11 h |
| November | 44°F | 30°F | 36.8°F | 2.20 | 6.3 | 13 | <1 | 19 | 9 h 30 min |
| December | 36°F | 24°F | 29.7°F | 1.93 | 16.5 | 13 | <1 | 28 | 8 h 40 min |
| Year (annual) | 57°F | 38°F | 47.6°F | 22.62 | 61.4 | 132 | 9 | 134 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 3°C | −4°C | −0.6°C | 46 mm | 41 cm |
| February | 5°C | −3°C | 0.7°C | 42 mm | 28 cm |
| March | 9°C | −1°C | 3.9°C | 54 mm | 22 cm |
| April | 12°C | 2°C | 6.9°C | 68 mm | 5 cm |
| May | 17°C | 6°C | 11.4°C | 71 mm | 1 cm |
| June | 21°C | 9°C | 14.8°C | 67 mm | 0 cm |
| July | 27°C | 13°C | 20.2°C | 29 mm | 0 cm |
| August | 27°C | 13°C | 20.3°C | 21 mm | 0 cm |
| September | 22°C | 9°C | 15.8°C | 27 mm | 0 cm |
| October | 14°C | 4°C | 8.9°C | 45 mm | 1 cm |
| November | 6°C | −1°C | 2.7°C | 56 mm | 16 cm |
| December | 2°C | −5°C | −1.3°C | 49 mm | 42 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00102159; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Cottonwood?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, August has the fewest days with rain (5).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00102159.
When is the last frost in Cottonwood?
In Cottonwood, the last spring frost (32°F) comes after May 6 in half of years and after May 26 in one year in ten; the first autumn frost comes before October 13 in half of years and before September 28 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 61 year in 10 after May 26; 9 in 10 after April 22
- First autumn frost, half of years before
- October 131 year in 10 before September 28; 9 in 10 before October 27
NOAA puts the median frost-free season at 156 days, and the season without a hard freeze (28°F) at 188 days.
A hard freeze (28°F) comes after April 21 in half of springs and before October 24 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Cottonwood in zone 6b in ZIP code 83533, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Cottonwood's NOAA station is in zone 7a: the coldest night of a typical year reaches 1°F (22 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Idaho · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00102159; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Cottonwood?
In a normal year in Cottonwood, 9 days a year reach 90°F, 134 nights fall to 32°F or colder and 132 days bring measurable precipitation.
- Days at 90°F or more
- 9a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 134a normal year
- Days that stay below freezing
- 27high of 32°F or less
- Days with 0.01 inch of precipitation
- 132a normal year
- Days with 1 inch of snow or more
- 20a normal year
The highest temperature in this station's record (since 1976) is 103°F, on August 10, 2018; the lowest is −20°F, on February 3, 1989.
The wettest calendar year on that record is 1990, with 27.62 in; the snowiest season is 2007–08, with 115.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00102159; records: ACIS (NOAA Regional Climate Centers), station USC00102159. Records use complete months only; a month missing more than three days is left out.
How sunny is Cottonwood?
Over a year 76% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Cottonwood, 4.0 kWh per square metre a day. July is the sunniest month (91%) and December the cloudiest (55%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 59% | 1.3 |
| February | 64% | 2.2 |
| March | 64% | 3.3 |
| April | 70% | 4.8 |
| May | 75% | 6.0 |
| June | 78% | 6.8 |
| July | 91% | 7.5 |
| August | 88% | 6.2 |
| September | 83% | 4.5 |
| October | 73% | 2.8 |
| November | 61% | 1.5 |
| December | 55% | 1.0 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Cottonwood need?
A normal year in Cottonwood brings 6,718 heating degree days, 25% more than the median U.S. place (5,373), and 393 cooling degree days, 57% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,010 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,057 | 0 |
| February | 889 | 0 |
| March | 805 | 0 |
| April | 615 | 0 |
| May | 390 | 6 |
| June | 215 | 28 |
| July | 51 | 155 |
| August | 43 | 156 |
| September | 184 | 47 |
| October | 528 | 3 |
| November | 847 | 0 |
| December | 1,094 | 0 |
| Year (annual) | 6,718 | 393 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00102159. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Cottonwood been warmer than normal lately?
2025 averaged 50.1°F, 2.5°F above the 1991-2020 normal of 47.6°F. 3 of the 4 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 47.2°F | −0.4°F | 25.45 | 86.2 |
| 2023 | 48.3°F | +0.7°F | 22.63 | 48.0 |
| 2024 | 49.4°F | +1.8°F | 19.87 | 51.5 |
| 2025 | 50.1°F | +2.5°F | 22.09 | 50.8 |
Source: observed years: ACIS, station USC00102159. A year counts only with all twelve months complete.
How does Cottonwood's climate compare?
Cottonwood is warmer than 53 of the other 84 places with their own NOAA record in Idaho, and wetter than 61. Across the 7,247 U.S. stations with normals, its annual mean of 47.6°F is warmer than 30%.
In the Köppen classification computed from these normals, Cottonwood is Dfb: continental, no dry season, warm summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Cottonwood share this climate record?
Ferdinand has no NOAA station with 1991-2020 normals of its own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Ferdinand, ID139 people · 8 mi N
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Cottonwood's climate
What is the coldest month in Cottonwood?
December, with a normal high of 36°F and a normal low of 24°F. The warmest is August (81°F by day, 56°F at night).
Does it snow in Cottonwood?
Yes: 61 inches in a normal year, falling on 33 days with 0.1 inch or more, the most in December (16.5 inches).
What is the rainiest month in Cottonwood?
May, with 2.78 in of precipitation in a normal year; the driest is August with 0.84 in.
What plant hardiness zone is Cottonwood in?
The USDA's 2023 map puts Cottonwood in zone 6b in ZIP code 83533, the nearest ZIP area. By the same method at Cottonwood's NOAA station, the coldest night of a typical year reaches 1°F (22 years, 1991-2020): zone 7a.
How late can frost come in Cottonwood?
In half of years the last 32°F night comes after May 6; in one year in ten it comes after May 26. Waiting until May 26 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Idaho climateThe statewide normals and every place in the state
- Grangeville, ID15 miles from this station, 47.5°F a year
- Nezperce, ID16 miles from this station, 44.9°F a year
- Winchester, ID18 miles from this station, 44.6°F a year
- Kamiah, ID22 miles from this station, 50.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made