Boise in Winter
In winter (December, January and February), Boise sees average daytime highs around 42°F and overnight lows near 28°F, with 4.9 in of precipitation over about 27 wet days across the season. It is the coldest season of the year and the wettest season of the year.
Over the season highs climb from about 42°F in early December to 49°F by late February. The sky is clear or mostly clear about 28% of the time across winter, and the air most often feels dry.
Winter is Boise's weakest season of the year to visit on our travel score. For the whole year in context, see Boise's year-round climate.
- Avg daytime high
- 42°F
- coldest season of the year
- Avg overnight low
- 28°F
- Precipitation
- 4.9 in
- 27 wet days
- Avg wind
- 7 mph
- Travel score
- 0.4
- weakest season of the year
- Months
- Dec · Jan · Feb
Temperature in Boise in Winter
Over the season highs climb from about 42°F in early December to 49°F by late February.
A typical winter day in Boise reaches about 42°F and drops to 28°F overnight. The warmest of the three months is February, the coolest January.
How winter really feels in Boise
Once humidity and wind are folded in, winter brings about 0 days that feel above 90°F and 90 that feel at or below 32°F.
The story in winter is cold — wind chill drags the overnight "feels like" below the raw low.
Boise weather by month
How the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 40° / 27° | 1.8 | 9.5 | 4.8 | 9.1 | 0.0 |
| Feb | 46° / 30° | 1.2 | 7.7 | 3 | 10.2 | 1.2 |
| Mar | 55° / 36° | 1.4 | 8.9 | 1.1 | 11.6 | 3.7 |
| Apr | 63° / 41° | 1.2 | 7.2 | 0.3 | 13.2 | 5.8 |
| May | 72° / 48° | 1.2 | 5.9 | 0.1 | 14.5 | 7.5 |
| Jun | 81° / 55° | 0.6 | 3.2 | 0 | 15.2 | 7.4 |
| Jul | 92° / 63° | 0.1 | 0.9 | 0 | 14.9 | 4.4 |
| Aug | 91° / 62° | 0.1 | 0.7 | 0 | 13.8 | 4.9 |
| Sep | 80° / 54° | 0.4 | 2.2 | 0 | 12.3 | 8.1 |
| Oct | 65° / 43° | 0.9 | 4.3 | 0.1 | 10.8 | 6.8 |
| Nov | 49° / 33° | 1.4 | 7.9 | 2 | 9.5 | 2.2 |
| Dec | 39° / 27° | 2.0 | 10.1 | 5.2 | 8.8 | 0.0 |
Cloud cover in Winter
The sky is clear or mostly clear about 28% of the time across winter.
Chance of precipitation in Winter
Boise gets around 4.9 in of rain and snow over 27 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 7 mph across winter.
Sunrise & sunset in Winter
Daylight runs from about 9 hours in early December to 10 h 48 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 2.2 kWh/m².
Is winter a good time to visit Boise?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a weaker month for outdoor sightseeing in Boise.
What to pack for Boise in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Boise sees daytime highs around 42°F and nights near 28°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 27 days see rain.
UV index in Boise in Winter
Clear-sky midday UV across winter averages around 2. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Boise peaks around July 13 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 2 | 4 | 5 | 8 | 9 | 9 | 7 | 6 | 4 | 2 | 1 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | Very high | Very high | High | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 2 | Moderate |
| Mar | 4 | Moderate |
| Apr | 5 | High |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 9 | Very high |
| Aug | 7 | Very high |
| Sep | 6 | High |
| Oct | 4 | Moderate |
| Nov | 2 | Low |
| Dec | 1 | Low |
Air quality in Boise in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter falls, not just the annual average.
Air quality in Boise is worst in August — around 45 µg/m³ PM2.5 (poor), about 6.0× the cleanest month (December, 7 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 8 | 9 | 10 | 10 | 10 | 8 | 20 | 45 | 21 | 15 | 9 | 7 |
| Level | Good | Good | Good | Good | Good | Good | Moderate | Poor | Moderate | Moderate | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 8 | Good |
| Feb | 9 | Good |
| Mar | 10 | Good |
| Apr | 10 | Good |
| May | 10 | Good |
| Jun | 8 | Good |
| Jul | 20 | Moderate |
| Aug | 45 | Poor |
| Sep | 21 | Moderate |
| Oct | 15 | Moderate |
| Nov | 9 | Good |
| Dec | 7 | Good |
Where is Boise?
Boise sits at 43.6°N, 116.2°W, 2,700 ft above sea level, in United States. The nearest listed city is Meridian, 9.3 mi away.
Topography around Boise
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Boise.
Within 2 miles, the terrain around Boise has only modest variations in elevation — a maximum elevation change of 535 ft around an average of 2,756 ft above sea level; within 10 miles, very significant variations in elevation — a maximum elevation change of 4,003 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 7,516 ft.
The land around Boise is covered by trees (42%) and artificial surfaces (39%) within 2 miles, grassland (55%) and trees (21%) within 10 miles, and grassland (61%) and trees (20%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Boise (43.6135°, -116.2035°, elevation 2,700 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.