Sun Valley weather in January

In January, Sun Valley sees average daytime highs of 40°F and overnight lows near 22°F, with 2.6 in of precipitation across 8 wet days and about 9.5 hours of daylight. It is the 11th-warmest and 1st-wettest month of the year here.

Day-to-day highs hold fairly steady near 40°F through the month. The sky is clear or mostly clear about 33% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 12 min at the start of January to 9 h 54 min by month's end. Set against the rest of the year, January is Sun Valley's 12th-clearest and 12th-windiest month. For the whole year in context, see Sun Valley's year-round climate.

Daytime high
40°
11th warmest
Overnight low
22°
2nd coldest
Precipitation
2.6 in
8 wet days
Daylight
9 h 30 min
7:24 AM – 4:53 PM
Cloud cover
59%
12th clearest
Wind
4 mph
12th windiest
Solar energy
2.73 kWh/m²
Travel score
0.0
out of 10

Sun Valley is place in Washoe County, Nevada, USA.

Density
500/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 40°F through the month.

A typical January day in Sun Valley reaches about 40°F in the afternoon and slips back to 22°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 30°F and 50°F. Set against its neighbours, January runs on par with December and about 4°F cooler than February.

20°40°60°151015202531
Avg high (°F)Avg low (°F)
13921
23921
33921
43922
53922
63922
73922
83922
93922
103922
113922
123922
133922
143922
154022
164022
174022
184022
194022
204022
214022
224022
234022
244023
254123
264123
274123
284123
294123
304223
314223

How January really feels in Sun Valley

Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 31 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
31
wind chill below the day's low

The story in January is cold — wind chill drags the overnight "feels like" below the raw low.

Sun Valley weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan40° / 22°2.686.89.50.0
Feb43° / 24°2.38.57.310.40.6
Mar50° / 28°2.28611.72.4
Apr57° / 34°1.36.93.6134.4
May67° / 42°1.26.81.214.16.8
Jun78° / 50°0.63.50.214.78.1
Jul87° / 56°0.42.8014.56.1
Aug85° / 56°0.32.7013.66.6
Sep77° / 50°0.42.5012.38.6
Oct64° / 40°0.93.50.810.97.0
Nov50° / 29°1.45.73.69.82.6
Dec39° / 21°2.57.66.69.30.1

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in January, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 14% of January, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14654
24654
34654
44654
54753
64753
74753
84654
94753
104753
114852
124852
134753
144753
154753
164852
174852
184852
194852
204753
214753
224753
234654
244654
254456
264555
274555
284456
294456
304456
314456

Chance of precipitation in January

Any precipitationSnow

Sun Valley gets around 2.6 in of rain and snow over 8 wet days in January, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 26% and peaks near 28% on the wettest days, and about 7 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
12421
22421
32421
42521
52521
62521
72521
82521
92521
102521
112621
122621
132622
142722
152722
162723
172823
182823
192823
202824
212824
222824
232723
242723
252623
262623
272622
282522
292522
302522
312522

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

Most of January feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, January lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
17100
18100
19100
20100
21100
22100
23100
24100
25100
26100
27100
28100
29100
30100
31100

Wind in January

Winds average 4 mph in January, the calmest month.

Across January, daily wind ranges from about 4 mph on the calmest days to 4 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 9 h 12 min at the start of January to 9 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over January. Sunrise moves from 7:25 AM to 7:15 AM, and sunset from 4:40 PM to 5:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.27:254:40
29.37:254:40
39.37:254:41
49.37:254:42
59.37:254:43
69.37:254:44
79.37:254:45
89.37:254:45
99.47:254:46
109.47:254:47
119.47:254:48
129.47:254:49
139.47:244:50
149.47:244:51
159.57:244:52
169.57:244:53
179.57:234:54
189.57:234:55
199.67:234:56
209.67:224:57
219.67:224:58
229.67:215:00
239.77:215:01
249.77:205:02
259.77:195:03
269.87:195:04
279.87:185:05
289.87:175:06
299.87:175:07
309.97:165:09
319.97:155:10

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.73 kWh/m².

For context, solar energy here swings from a low near 2.42 kWh/m² to a high of 8.26 kWh/m² in June across the year — January's 2.73 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
12.5Moderate
22.5Moderate
32.5Moderate
42.5Moderate
52.6Moderate
62.6Moderate
72.6Moderate
82.6Moderate
92.6Moderate
102.6Moderate
112.6Moderate
122.6Moderate
132.7Moderate
142.7Moderate
152.7Moderate
162.7Moderate
172.8Moderate
182.8Moderate
192.8Moderate
202.8Moderate
212.9Moderate
222.9Moderate
232.9Moderate
243.0Moderate
253.0Moderate
263.0Moderate
273.1Moderate
283.1Moderate
293.1Moderate
303.2Moderate
313.2Moderate
Planning a trip in January

Is January a good time to visit Sun Valley?

Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

0.0
Sightseeing
12th-best month of the year
0.0
Beach & pool
9th-best month of the year

January is a weaker month for outdoor sightseeing in Sun Valley.

What to pack for Sun Valley in January

From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In January, Sun Valley sees daytime highs around 40°F and nights near 22°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 8 days see rain.

a warm layera heavy coatrain gear

UV index in Sun Valley in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 3. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sun Valley peaks around June 22 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 23 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateJun 22UV 11Nov 23UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5Moderate
Apr7High
May9Very high
Jun11Extreme
Jul11Extreme
Aug10Very high
Sep7High
Oct5High
Nov2Moderate
Dec2Moderate

Air quality in Sun Valley in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.

Air quality in Sun Valley is worst in July — around 51 µg/m³ PM2.5 (poor), about 8.5× the cleanest month (December, 6 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecGoodPoorModerateGoodJul 2149 µg/m³Dec 176 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb8Good
Mar10Good
Apr10Good
May10Good
Jun10Good
Jul51Poor
Aug42Poor
Sep45Poor
Oct15Moderate
Nov7Good
Dec6Good
Location & terrain

Where is Sun Valley?

Sun Valley sits at 39.6°N, 119.8°W, 4,724 ft above sea level, in United States. The nearest listed city is Sparks, 4.3 mi away.

Topography around Sun Valley

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Sun Valley.

Within 2 miles, the terrain around Sun Valley has significant variations in elevation — a maximum elevation change of 1,112 ft around an average of 4,898 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,911 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 7,779 ft.

The land around Sun Valley is covered by grassland (51%) and artificial surfaces (31%) within 2 miles, grassland (55%) and artificial surfaces (22%) within 10 miles, and grassland (40%) and trees (29%) within 50 miles.

2 miles
1,112 ft
10 miles
3,911 ft
50 miles
7,779 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Sparks 4.3 mi · Reno 5.0 mi · Spanish Springs 5.0 mi · Fernley 28 mi · Truckee 29 mi · Carson City 30 mi · Lake Tahoe 47 mi · Susanville 73 mi

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
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Sun Valley (39.5963°, -119.776°, elevation 4,724 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. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).