Grangeville, Idaho climate: Normal weather by month, frost dates and records
Grangeville's normal year runs from 24°F December nights to 82°F July afternoons, with 23.5 inches of precipitation and 39 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.6°C, December lows of −5°C, July highs of 28°C, 597 mm of precipitation a year.
- NOAA stationGrangeville
- Station IDUSC00103771
- Location45.94°N 116.12°W
- Elevation3,300 ft (1,006 m)
- Population3,627
On October 23, the normal high in Grangeville is 54°F and the normal low 35°F, and the chance of measurable rain or snow is 32%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Grangeville.
- Jan 38° 25°
- Feb 42° 25°
- Mar 49° 29°
- Apr 56° 34°
- May 64° 42°
- Jun 70° 48°
- Jul 82° 54°
- Aug 83° 53°
- Sep 73° 45°
- Oct 58° 37°
- Nov 45° 29°
- Dec 37° 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 Grangeville each month?
July is the warmest month, with normal highs of 82°F; December the coldest, with normal lows of 24°F. The most precipitation falls in May (3.44 in), the least in August (0.90 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 38°F | 25°F | 31.2°F | 1.27 | 7.9 | 10 | <1 | 26 | 9 h |
| February | 42°F | 25°F | 33.7°F | 1.43 | 6.2 | 8 | <1 | 24 | 10 h 20 min |
| March | 49°F | 29°F | 39.4°F | 2.31 | 6.0 | 11 | <1 | 21 | 11 h 50 min |
| April | 56°F | 34°F | 45.1°F | 2.90 | 3.2 | 14 | <1 | 13 | 13 h 30 min |
| May | 64°F | 42°F | 52.7°F | 3.44 | 0.2 | 13 | <1 | 3 | 14 h 50 min |
| June | 70°F | 48°F | 58.9°F | 3.26 | 0.0 | 12 | <1 | <1 | 15 h 40 min |
| July | 82°F | 54°F | 67.9°F | 1.07 | 0.0 | 6 | 6 | <1 | 15 h 30 min |
| August | 83°F | 53°F | 67.7°F | 0.90 | 0.0 | 5 | 7 | <1 | 14 h 10 min |
| September | 73°F | 45°F | 58.9°F | 1.30 | 0.0 | 5 | 1 | 1 | 12 h 40 min |
| October | 58°F | 37°F | 47.0°F | 1.93 | 0.6 | 10 | <1 | 10 | 11 h |
| November | 45°F | 29°F | 37.0°F | 1.91 | 5.0 | 11 | <1 | 21 | 9 h 30 min |
| December | 37°F | 24°F | 30.4°F | 1.79 | 9.6 | 10 | <1 | 27 | 8 h 40 min |
| Year (annual) | 58°F | 37°F | 47.5°F | 23.51 | 38.7 | 114 | 14 | 145 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 3°C | −4°C | −0.4°C | 32 mm | 20 cm |
| February | 6°C | −4°C | 0.9°C | 36 mm | 16 cm |
| March | 10°C | −1°C | 4.1°C | 59 mm | 15 cm |
| April | 13°C | 1°C | 7.3°C | 74 mm | 8 cm |
| May | 18°C | 5°C | 11.5°C | 87 mm | 1 cm |
| June | 21°C | 9°C | 14.9°C | 83 mm | 0 cm |
| July | 28°C | 12°C | 19.9°C | 27 mm | 0 cm |
| August | 28°C | 12°C | 19.8°C | 23 mm | 0 cm |
| September | 23°C | 7°C | 14.9°C | 33 mm | 0 cm |
| October | 14°C | 3°C | 8.3°C | 49 mm | 2 cm |
| November | 7°C | −2°C | 2.8°C | 49 mm | 13 cm |
| December | 3°C | −5°C | −0.9°C | 45 mm | 24 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00103771; 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 Grangeville?
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 USC00103771.
When is the last frost in Grangeville?
In Grangeville, the last spring frost (32°F) comes after May 9 in half of years and after May 27 in one year in ten; the first autumn frost comes before October 3 in half of years and before September 14 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 91 year in 10 after May 27; 9 in 10 after April 24
- First autumn frost, half of years before
- October 31 year in 10 before September 14; 9 in 10 before October 17
NOAA puts the median frost-free season at 146 days, and the season without a hard freeze (28°F) at 176 days.
A hard freeze (28°F) comes after April 22 in half of springs and before October 15 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Grangeville in zone 6b in ZIP code 83530, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Grangeville's NOAA station is in zone 6b: the coldest night of a typical year reaches −2°F (18 complete years).
Frost dates for every NOAA station in Idaho · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00103771; 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 Grangeville?
In a normal year in Grangeville, 14 days a year reach 90°F, 145 nights fall to 32°F or colder and 114 days bring measurable precipitation.
- Days at 90°F or more
- 14a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 145a normal year
- Days that stay below freezing
- 23high of 32°F or less
- Days with 0.01 inch of precipitation
- 114a normal year
- Days with 1 inch of snow or more
- 13a normal year
The highest temperature in this station's record (since 1893) is 108°F, on July 27, 1934; the lowest is −25°F, on December 30, 1968.
The wettest calendar year on that record is 1975, with 32.67 in; the snowiest season is 1968–69, with 82.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00103771; records: ACIS (NOAA Regional Climate Centers), station USC00103771. Records use complete months only; a month missing more than three days is left out.
How sunny is Grangeville?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Grangeville, 4.1 kWh per square metre a day. July is the sunniest month (90%) and December the cloudiest (56%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 62% | 1.5 |
| February | 65% | 2.4 |
| March | 64% | 3.4 |
| April | 67% | 4.7 |
| May | 71% | 5.9 |
| June | 77% | 6.8 |
| July | 90% | 7.6 |
| August | 89% | 6.4 |
| September | 83% | 4.7 |
| October | 73% | 2.9 |
| November | 62% | 1.6 |
| December | 56% | 1.1 |
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 Grangeville need?
A normal year in Grangeville brings 6,675 heating degree days, 24% more than the median U.S. place (5,373), and 313 cooling degree days, 65% 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 1,888 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,049 | 0 |
| February | 876 | 0 |
| March | 795 | 0 |
| April | 597 | 0 |
| May | 385 | 4 |
| June | 202 | 19 |
| July | 44 | 133 |
| August | 46 | 130 |
| September | 210 | 27 |
| October | 557 | 0 |
| November | 840 | 0 |
| December | 1,074 | 0 |
| Year (annual) | 6,675 | 313 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00103771. 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.
How does Grangeville's climate compare?
Grangeville is warmer than 52 of the other 84 places with their own NOAA record in Idaho, and wetter than 63. Across the 7,247 U.S. stations with normals, its annual mean of 47.5°F is warmer than 30%.
In the Köppen classification computed from these normals, Grangeville 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 Grangeville share this climate record?
White Bird 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.
- White Bird, ID87 people · 15 mi SW
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 Grangeville's climate
What is the coldest month in Grangeville?
December, with a normal high of 37°F and a normal low of 24°F. The warmest is July (82°F by day, 54°F at night).
Does it snow in Grangeville?
Yes: 39 inches in a normal year, falling on 17 days with 0.1 inch or more, the most in December (9.6 inches).
What is the rainiest month in Grangeville?
May, with 3.44 in of precipitation in a normal year; the driest is August with 0.90 in.
What plant hardiness zone is Grangeville in?
The USDA's 2023 map puts Grangeville in zone 6b in ZIP code 83530, the nearest ZIP area. By the same method at Grangeville's NOAA station, the coldest night of a typical year reaches −2°F (18 years, 1991-2020): zone 6b.
How late can frost come in Grangeville?
In half of years the last 32°F night comes after May 9; in one year in ten it comes after May 27. Waiting until May 27 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Idaho climateThe statewide normals and every place in the state
- Kooskia, ID12 miles from this station, 49.2°F a year
- Cottonwood, ID15 miles from this station, 47.6°F a year
- Kamiah, ID21 miles from this station, 50.9°F a year
- Nezperce, ID21 miles from this station, 44.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made