Boise, Oklahoma climate: Normal weather by month, frost dates and records
Boise's normal year runs from 20°F January nights to 94°F July afternoons, with 18.3 inches of precipitation and 32 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 13.6°C, January lows of −6°C, July highs of 34°C, 466 mm of precipitation a year.
- NOAA stationBoise City (2 mi E)
- Station IDUSC00340908
- Location36.72°N 102.48°W
- Elevation4,133 ft (1,260 m)
- Population1,077
On October 14, the normal high in Boise is 74°F and the normal low 41°F, and the chance of measurable rain or snow is 11%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Boise.
- Jan 52° 20°
- Feb 56° 23°
- Mar 64° 30°
- Apr 72° 38°
- May 80° 47°
- Jun 90° 58°
- Jul 94° 63°
- Aug 91° 62°
- Sep 85° 54°
- Oct 74° 40°
- Nov 61° 29°
- Dec 51° 22°
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 Boise each month?
July is the warmest month, with normal highs of 94°F; January the coldest, with normal lows of 20°F. The most precipitation falls in August (3.23 in), the least in February (0.36 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 52°F | 20°F | 36.1°F | 0.50 | 7.3 | 3 | <1 | 29 | 9 h 50 min |
| February | 56°F | 23°F | 39.1°F | 0.36 | 2.5 | 3 | <1 | 25 | 10 h 50 min |
| March | 64°F | 30°F | 46.8°F | 1.10 | 7.2 | 4 | <1 | 20 | 11 h 50 min |
| April | 72°F | 38°F | 54.5°F | 1.40 | 2.3 | 4 | 1 | 7 | 13 h 10 min |
| May | 80°F | 47°F | 63.8°F | 1.82 | 0.2 | 6 | 5 | 1 | 14 h 10 min |
| June | 90°F | 58°F | 74.0°F | 2.28 | 0.0 | 6 | 17 | <1 | 14 h 40 min |
| July | 94°F | 63°F | 78.3°F | 3.12 | 0.0 | 7 | 24 | <1 | 14 h 30 min |
| August | 91°F | 62°F | 76.1°F | 3.23 | 0.0 | 7 | 19 | <1 | 13 h 40 min |
| September | 85°F | 54°F | 69.2°F | 1.75 | 0.0 | 4 | 9 | <1 | 12 h 30 min |
| October | 74°F | 40°F | 57.0°F | 1.48 | 1.3 | 3 | 1 | 5 | 11 h 20 min |
| November | 61°F | 29°F | 45.3°F | 0.56 | 3.1 | 3 | <1 | 20 | 10 h 10 min |
| December | 51°F | 22°F | 36.5°F | 0.74 | 7.9 | 3 | <1 | 29 | 9 h 40 min |
| Year (annual) | 72°F | 40°F | 56.4°F | 18.34 | 31.8 | 52 | 74 | 135 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 11°C | −6°C | 2.3°C | 13 mm | 19 cm |
| February | 13°C | −5°C | 3.9°C | 9 mm | 6 cm |
| March | 18°C | −1°C | 8.2°C | 28 mm | 18 cm |
| April | 22°C | 3°C | 12.5°C | 36 mm | 6 cm |
| May | 27°C | 8°C | 17.7°C | 46 mm | 1 cm |
| June | 32°C | 14°C | 23.3°C | 58 mm | 0 cm |
| July | 34°C | 17°C | 25.7°C | 79 mm | 0 cm |
| August | 33°C | 16°C | 24.5°C | 82 mm | 0 cm |
| September | 29°C | 12°C | 20.7°C | 44 mm | 0 cm |
| October | 23°C | 5°C | 13.9°C | 38 mm | 3 cm |
| November | 16°C | −1°C | 7.4°C | 14 mm | 8 cm |
| December | 11°C | −6°C | 2.5°C | 19 mm | 20 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00340908; 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 Boise?
Normal highs sit between 65°F and 85°F in April, May, September and October. Of those, October has the fewest days with rain (3).
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 USC00340908.
When is the last frost in Boise?
In Boise, the last spring frost (32°F) comes after April 26 in half of years and after May 9 in one year in ten; the first autumn frost comes before October 17 in half of years and before October 4 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
- April 261 year in 10 after May 9; 9 in 10 after April 10
- First autumn frost, half of years before
- October 171 year in 10 before October 4; 9 in 10 before October 29
NOAA puts the median frost-free season at 173 days, and the season without a hard freeze (28°F) at 193 days.
A hard freeze (28°F) comes after April 15 in half of springs and before October 25 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Boise in zone 6b in ZIP code 73933, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Boise's NOAA station is in zone 6b: the coldest night of a typical year reaches −3°F (25 complete years).
Frost dates for every NOAA station in Oklahoma · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00340908; 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 Boise?
In a normal year in Boise, 74 days a year reach 90°F (10 of them 100°F or more), 135 nights fall to 32°F or colder and 52 days bring measurable precipitation.
- Days at 90°F or more
- 74a normal year
- Days at 100°F or more
- 10a normal year
- Nights at 32°F or colder
- 135a normal year
- Days that stay below freezing
- 9high of 32°F or less
- Days with 0.01 inch of precipitation
- 52a normal year
- Days with 1 inch of snow or more
- 10a normal year
The highest temperature in this station's record (since 1908) is 109°F, on June 29, 1998; the lowest is −24°F, on January 4, 1959.
The wettest calendar year on that record is 2015, with 31.88 in; the snowiest season is 1997–98, with 64.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00340908; records: ACIS (NOAA Regional Climate Centers), station USC00340908. Records use complete months only; a month missing more than three days is left out.
How sunny is Boise?
Over a year 86% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Boise, 5.3 kWh per square metre a day. July is the sunniest month (90%) and February the cloudiest (79%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 82% | 3.0 |
| February | 79% | 3.8 |
| March | 82% | 5.2 |
| April | 83% | 6.4 |
| May | 85% | 7.3 |
| June | 89% | 7.8 |
| July | 90% | 7.5 |
| August | 88% | 6.6 |
| September | 89% | 5.7 |
| October | 85% | 4.3 |
| November | 85% | 3.3 |
| December | 80% | 2.6 |
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 Boise need?
A normal year in Boise brings 4,405 heating degree days, 18% fewer than the median U.S. place (5,373), and 1,305 cooling degree days, 44% more than the median (908). Six months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,009 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 896 | 0 |
| February | 724 | 0 |
| March | 563 | 1 |
| April | 322 | 9 |
| May | 113 | 78 |
| June | 7 | 277 |
| July | 1 | 413 |
| August | 2 | 347 |
| September | 37 | 163 |
| October | 267 | 18 |
| November | 590 | 0 |
| December | 883 | 0 |
| Year (annual) | 4,405 | 1,305 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00340908. 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 Boise been warmer than normal lately?
Over 74 complete years from 1909 to 2016, the station's annual mean temperature rose at a fitted 1.0°F per century (+0.05°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Boise's climate compare?
Boise is warmer than 2 of the other 133 places with their own NOAA record in Oklahoma, and wetter than 2. Across the 7,247 U.S. stations with normals, its annual mean of 56.4°F is warmer than 65%.
In the Köppen classification computed from these normals, Boise is BSk: cold semi-arid steppe. 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 Boise's climate
What is the coldest month in Boise?
January, with a normal high of 52°F and a normal low of 20°F. The warmest is July (94°F by day, 63°F at night).
Does it snow in Boise?
Yes: 32 inches in a normal year, falling on 12 days with 0.1 inch or more, the most in December (7.9 inches).
What is the rainiest month in Boise?
August, with 3.23 in of precipitation in a normal year; the driest is February with 0.36 in.
What plant hardiness zone is Boise in?
The USDA's 2023 map puts Boise in zone 6b in ZIP code 73933, the nearest ZIP area. By the same method at Boise's NOAA station, the coldest night of a typical year reaches −3°F (25 years, 1991-2020): zone 6b.
How late can frost come in Boise?
In half of years the last 32°F night comes after April 26; in one year in ten it comes after May 9. Waiting until May 9 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Oklahoma climateThe statewide normals and every place in the state
- Campo, CO21 miles from this station, 54.3°F a year
- Kenton, OK30 miles from this station, 56.0°F a year
- Stratford, TX30 miles from this station, 56.5°F a year
- Elkhart, KS38 miles from this station, 56.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made