Boise weather in January: Boise, Idaho: normal highs, lows, rain and records for January
Boise in January has a normal high of 39°F and a normal low of 26°F, a daily mean of 32°F, rising from 37°F on the 1st to 41°F by the 31st. Measurable precipitation falls on 11 days in a normal January, 1.41 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 4°C and low of −4°C, 36 mm of precipitation and 13 cm of snow in January.
- NOAA stationBoise Air Terminal
- Station IDUSW00024131
- Location43.57°N 116.24°W
- Elevation2,814 ft (858 m)
- From the center2 miles
- Population237,963
- Jan 39° 26°
- Feb 46° 29°
- Mar 56° 35°
- Apr 62° 40°
- May 72° 48°
- Jun 81° 54°
- Jul 93° 62°
- Aug 91° 61°
- Sep 80° 53°
- Oct 65° 42°
- Nov 49° 32°
- Dec 39° 25°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is Boise in January?
The normal high is 39°F and the normal low 26°F, for a daily mean of 32.2°F. January is 0.1°F warmer than December and 5.3°F cooler than February. January is the 11th warmest month of the year in Boise and the 3rd wettest. Across the month the normal high rises 4°F, from 37°F on January 1 to 41°F on January 31. From one year to the next January's mean temperature typically moves about 4.8°F either way (NOAA's standard deviation), so roughly two Januarys in three average between 27°F and 37°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 38%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| January 1 | 37°F | 24°F | 38% | 16% |
| January 8 | 38°F | 25°F | 37% | 16% |
| January 15 | 38°F | 25°F | 36% | 16% |
| January 22 | 39°F | 26°F | 35% | 16% |
| January 31 | 41°F | 27°F | 34% | 15% |
Every day of January: normal high, low and chance of precipitation (warmest afternoon January 31, coldest night January 1)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| January 1 | 37°F | 24°F | 38% | 16% | 9 h |
| January 2 | 37°F | 24°F | 38% | 16% | 9 h |
| January 3 | 37°F | 25°F | 37% | 16% | 9 h |
| January 4 | 38°F | 25°F | 37% | 16% | 9 h |
| January 5 | 38°F | 25°F | 37% | 16% | 9 h |
| January 6 | 38°F | 25°F | 37% | 16% | 9 h |
| January 7 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 8 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 9 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 10 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 11 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 12 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 13 | 38°F | 25°F | 37% | 16% | 9 h 10 min |
| January 14 | 38°F | 25°F | 37% | 16% | 9 h 20 min |
| January 15 | 38°F | 25°F | 36% | 16% | 9 h 20 min |
| January 16 | 39°F | 25°F | 36% | 16% | 9 h 20 min |
| January 17 | 39°F | 26°F | 36% | 16% | 9 h 20 min |
| January 18 | 39°F | 26°F | 36% | 16% | 9 h 20 min |
| January 19 | 39°F | 26°F | 36% | 16% | 9 h 20 min |
| January 20 | 39°F | 26°F | 36% | 16% | 9 h 30 min |
| January 21 | 39°F | 26°F | 36% | 16% | 9 h 30 min |
| January 22 | 39°F | 26°F | 35% | 16% | 9 h 30 min |
| January 23 | 40°F | 26°F | 35% | 16% | 9 h 30 min |
| January 24 | 40°F | 26°F | 35% | 16% | 9 h 30 min |
| January 25 | 40°F | 26°F | 35% | 16% | 9 h 40 min |
| January 26 | 40°F | 26°F | 35% | 16% | 9 h 40 min |
| January 27 | 40°F | 27°F | 35% | 16% | 9 h 40 min |
| January 28 | 41°F | 27°F | 34% | 16% | 9 h 40 min |
| January 29 | 41°F | 27°F | 34% | 16% | 9 h 40 min |
| January 30 | 41°F | 27°F | 34% | 15% | 9 h 50 min |
| January 31 | 41°F | 27°F | 34% | 15% | 9 h 50 min |
- Normal high
- 39°FJanuary average
- Normal low
- 26°FJanuary average
- Precipitation
- 1.41 inmonth total
- Days with precipitation
- 110.01 inch or more
- Snowfall
- 5.3 inmonth total
- Nights at 32°F or colder
- 26
- Daylight
- 9 h to 9 h 50 minJanuary 1 to January 31
- Sunshine
- 64%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USW00024131; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain or snow in Boise in January?
On a given January day the chance of 0.01 inch or more is 36% on average, highest around January 1 (38%). In all, 1.41 in falls on 11 days of a normal January.
In a normal January in Boise, 26 nights fall to freezing, 6 days stay below freezing all day and snowfall averages 5.3 inches.
Snow falls on 5 days in a normal January, and an inch or more covers the ground on 6 days.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USW00024131.
How humid and windy is Boise in January?
At 3 p.m. the normal temperature is 41°F with 58% relative humidity and a dew point of 27°F; at 6 a.m. it is 30°F with 81% humidity. The wind averages 6.8 mph, most often from the northwest in the afternoon. A dew point under 50°F feels dry.
| Time | Temperature | Dew point | Humidity | Wind | Clear or few clouds |
|---|---|---|---|---|---|
| 6 a.m. | 30°F | 25°F | 81% | 6.1 mph | – |
| 9 a.m. | 30°F | 25°F | 80% | 6.3 mph | – |
| noon | 37°F | 27°F | 66% | 7.5 mph | 53% |
| 3 p.m. | 41°F | 27°F | 58% | 8.6 mph | 52% |
| 6 p.m. | 38°F | 27°F | 65% | 7.1 mph | 52% |
| 9 p.m. | 34°F | 27°F | 76% | 6.3 mph | 54% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00024131. Hourly normals exist only for NOAA's first-order stations; a dash where NOAA publishes no value for that hour (the sky at some hours).
What are the records for January in Boise?
The warmest January temperature on Boise's official record (since 1875) is 66°F, on January 31, 2024; the coldest is −28°F, on January 16, 1888. The wettest January brought 4.33 in (1909); the snowiest, 27.0 inches (1929).
The January mean against the 1991-2020 normal of 32.2°F: 2021 36.4°F (+4.2), 2022 28.9°F (−3.3), 2023 33.5°F (+1.3), 2024 33.2°F (+1.0), 2025 31.4°F (−0.8), 2026 33.6°F (+1.4). 4 of 6 ran warmer than normal.
| January | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 36.4°F | +4.2°F | 1.24 in |
| 2022 | 28.9°F | −3.3°F | 1.08 in |
| 2023 | 33.5°F | +1.3°F | 0.71 in |
| 2024 | 33.2°F | +1.0°F | 2.23 in |
| 2025 | 31.4°F | −0.8°F | 1.07 in |
| 2026 | 33.6°F | +1.4°F | 0.73 in |
Source: records: ACIS, NWS threaded record BOIthr; recent months: ACIS, station USW00024131. Records and recent months use complete months only.
How does January in Boise compare across Idaho?
Across the 85 places PlainClimate covers in Idaho, January normal highs run from 27°F in Island Park to 44°F in Glenns Ferry; Boise's is 39°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.