Grace, Idaho climate: Normal weather by month, frost dates and records
Grace's normal year runs from 13°F January nights to 85°F July afternoons, with 15.1 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 6.5°C, January lows of −10°C, July highs of 30°C, 382 mm of precipitation a year.
- NOAA stationGrace
- Station IDUSC00103732
- Location42.59°N 111.73°W
- Elevation5,550 ft (1,692 m)
- Population945
On October 22, the normal high in Grace is 56°F and the normal low 30°F, and the chance of measurable rain or snow is 24%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Grace.
- Jan 31° 13°
- Feb 34° 16°
- Mar 44° 24°
- Apr 54° 31°
- May 64° 38°
- Jun 74° 44°
- Jul 85° 50°
- Aug 84° 49°
- Sep 73° 41°
- Oct 59° 32°
- Nov 43° 23°
- Dec 32° 14°
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 Grace each month?
July is the warmest month, with normal highs of 85°F; January the coldest, with normal lows of 13°F. The most precipitation falls in May (2.38 in), the least in July (0.76 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 31°F | 13°F | 21.9°F | 1.13 | 9 | <1 | 31 | 9 h 20 min |
| February | 34°F | 16°F | 25.0°F | 0.98 | 9 | <1 | 27 | 10 h 30 min |
| March | 44°F | 24°F | 33.8°F | 1.30 | 9 | <1 | 28 | 11 h 50 min |
| April | 54°F | 31°F | 42.2°F | 1.45 | 10 | <1 | 21 | 13 h 20 min |
| May | 64°F | 38°F | 50.8°F | 2.38 | 12 | <1 | 8 | 14 h 30 min |
| June | 74°F | 44°F | 59.2°F | 1.32 | 7 | 2 | 2 | 15 h 20 min |
| July | 85°F | 50°F | 67.7°F | 0.76 | 5 | 12 | <1 | 15 h |
| August | 84°F | 49°F | 66.3°F | 1.04 | 6 | 10 | <1 | 14 h |
| September | 73°F | 41°F | 57.2°F | 1.38 | 6 | 1 | 5 | 12 h 30 min |
| October | 59°F | 32°F | 45.2°F | 1.40 | 8 | <1 | 20 | 11 h 10 min |
| November | 43°F | 23°F | 32.8°F | 0.92 | 8 | <1 | 27 | 9 h 50 min |
| December | 32°F | 14°F | 23.0°F | 0.99 | 10 | <1 | 30 | 9 h |
| Year (annual) | 56°F | 31°F | 43.7°F | 15.05 | 99 | 25 | 200 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | −1°C | −10°C | −5.6°C | 29 mm |
| February | 1°C | −9°C | −3.9°C | 25 mm |
| March | 7°C | −5°C | 1.0°C | 33 mm |
| April | 12°C | −1°C | 5.7°C | 37 mm |
| May | 18°C | 3°C | 10.4°C | 60 mm |
| June | 24°C | 7°C | 15.1°C | 34 mm |
| July | 30°C | 10°C | 19.8°C | 19 mm |
| August | 29°C | 9°C | 19.1°C | 26 mm |
| September | 23°C | 5°C | 14.0°C | 35 mm |
| October | 15°C | 0°C | 7.3°C | 36 mm |
| November | 6°C | −5°C | 0.4°C | 23 mm |
| December | 0°C | −10°C | −5.0°C | 25 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, McCammon (24 miles away), gets 45 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00103732; 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 Grace?
Normal highs sit between 65°F and 85°F in June, August and September. Of those, August has the fewest days with rain (6).
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 USC00103732.
When is the last frost in Grace?
In Grace, the last spring frost (32°F) comes after May 29 in half of years and after June 16 in one year in ten; the first autumn frost comes before September 17 in half of years and before September 1 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 291 year in 10 after June 16; 9 in 10 after May 11
- First autumn frost, half of years before
- September 171 year in 10 before September 1; 9 in 10 before October 1
NOAA puts the median frost-free season at 111 days, and the season without a hard freeze (28°F) at 143 days.
A hard freeze (28°F) comes after May 9 in half of springs and before October 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Grace in zone 5b in ZIP code 83241, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Grace's NOAA station is in zone 5a: the coldest night of a typical year reaches −17°F (26 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 USC00103732; 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 Grace?
In a normal year in Grace, 25 days a year reach 90°F (1 of them 100°F or more), 200 nights fall to 32°F or colder and 99 days bring measurable precipitation.
- Days at 90°F or more
- 25a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 200a normal year
- Days that stay below freezing
- 41high of 32°F or less
- Days with 0.01 inch of precipitation
- 99a normal year
The highest temperature in this station's record (since 1907) is 103°F, on July 10, 1919; the lowest is −40°F, on February 9, 1933.
The wettest calendar year on that record is 2016, with 21.31 in; the snowiest season is 1951–52, with 127.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00103732; records: ACIS (NOAA Regional Climate Centers), station USC00103732. Records use complete months only; a month missing more than three days is left out.
How sunny is Grace?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Grace, 4.5 kWh per square metre a day. July is the sunniest month (89%) and December the cloudiest (61%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 67% | 1.9 |
| February | 66% | 2.8 |
| March | 71% | 4.1 |
| April | 72% | 5.4 |
| May | 74% | 6.3 |
| June | 83% | 7.5 |
| July | 89% | 7.6 |
| August | 88% | 6.6 |
| September | 84% | 5.2 |
| October | 76% | 3.4 |
| November | 68% | 2.1 |
| December | 61% | 1.5 |
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 Grace need?
A normal year in Grace brings 7,955 heating degree days, 48% more than the median U.S. place (5,373), and 238 cooling degree days, 74% 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 1,749 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,336 | 0 |
| February | 1,119 | 0 |
| March | 967 | 0 |
| April | 684 | 0 |
| May | 441 | 1 |
| June | 194 | 20 |
| July | 35 | 117 |
| August | 49 | 89 |
| September | 246 | 10 |
| October | 614 | 0 |
| November | 968 | 0 |
| December | 1,302 | 0 |
| Year (annual) | 7,955 | 238 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00103732. 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 Grace been warmer than normal lately?
2022 averaged 42.2°F, 1.5°F below the 1991-2020 normal of 43.7°F. 1 of the 2 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 45.4°F | +1.7°F | 16.34 |
| 2022 | 42.2°F | −1.5°F | 13.18 |
Over 81 complete years from 1909 to 2025, the station's annual mean temperature rose at a fitted 2.1°F per century (+0.12°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00103732; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Grace's climate compare?
Grace is warmer than 19 of the other 84 places with their own NOAA record in Idaho, and wetter than 41. Across the 7,247 U.S. stations with normals, its annual mean of 43.7°F is warmer than 14%.
In the Köppen classification computed from these normals, Grace 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.
Questions about Grace's climate
What is the coldest month in Grace?
January, with a normal high of 31°F and a normal low of 13°F. The warmest is July (85°F by day, 50°F at night).
Does it snow in Grace?
Yes. NOAA publishes no 1991-2020 snowfall normal for Grace's NOAA station; the nearest record that keeps one, McCammon (24 miles away), records 45 inches of snow in a normal year.
What is the rainiest month in Grace?
May, with 2.38 in of precipitation in a normal year; the driest is July with 0.76 in.
What plant hardiness zone is Grace in?
The USDA's 2023 map puts Grace in zone 5b in ZIP code 83241, the nearest ZIP area. By the same method at Grace's NOAA station, the coldest night of a typical year reaches −17°F (26 years, 1991-2020): zone 5a.
How late can frost come in Grace?
In half of years the last 32°F night comes after May 29; in one year in ten it comes after June 16. Waiting until June 16 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Idaho climateThe statewide normals and every place in the state
- Soda Springs, ID9 miles from this station, 42.4°F a year
- Lava Hot Springs, ID14 miles from this station, 45.0°F a year
- Downey, ID23 miles from this station, 45.6°F a year
- McCammon, ID24 miles from this station, 46.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made