Ukiah weather in January

In January, Ukiah sees average daytime highs of 54°F and overnight lows near 37°F, with 7.2 in of precipitation across 12.4 wet days and about 9.6 hours of daylight. It is the 11th-warmest and 2nd-wettest month of the year here.

Highs climb over the month, from about 52°F in the first days to 55°F by the end. The sky is clear or mostly clear about 29% of the time in January, and the air most often feels dry.

Daylight stretches from about 9 h 18 min at the start of January to 9 h 54 min by month's end. Set against the rest of the year, January is Ukiah's 12th-clearest and 7th-windiest month. For the whole year in context, see Ukiah's year-round climate.

Daytime high
54°
11th warmest
Overnight low
37°
2nd coldest
Precipitation
7.2 in
12.4 wet days
Daylight
9 h 30 min
7:36 AM – 5:08 PM
Cloud cover
64%
12th clearest
Wind
4 mph
7th windiest
Solar energy
2.1 kWh/m²
Travel score
3.0
out of 10

Ukiah is city in and county seat of Mendocino County, California, United States.

Density
1,301/km²
people per km²
Founded
1876

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

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 52°F in the first days to 55°F by the end.

A typical January day in Ukiah reaches about 54°F in the afternoon and slips back to 37°F overnight — a 17°F spread between the day's warmth and the night's chill. On most days the high lands between 46°F and 63°F. Set against its neighbours, January runs on par with December and about 2°F cooler than February.

20°30°40°50°60°70°151015202531
Avg high (°F)Avg low (°F)
15235
25236
35236
45236
55336
65336
75336
85336
95336
105336
115337
125337
135337
145337
155437
165437
175437
185437
195437
205437
215437
225437
235537
245537
255537
265537
275537
285537
295537
305537
315637

How January really feels in Ukiah

Once humidity and wind are folded in, January averages 0 days that feel above 90°F and 1 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
1
wind chill below the day's low

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

Ukiah weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan54° / 37°7.212.41.99.63.0
Feb56° / 38°6.710.82.310.53.6
Mar59° / 40°6.011.8211.74.5
Apr63° / 42°3.18.30.5135.9
May70° / 47°1.95.4014.17.5
Jun78° / 53°0.62.2014.78.6
Jul85° / 57°0.00.3014.57.1
Aug85° / 57°0.10.4013.57.2
Sep82° / 54°0.31.4012.38.3
Oct73° / 47°2.24.60118.1
Nov60° / 40°4.38.50.39.95.0
Dec53° / 36°7.812.21.39.32.9

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% of the time in January, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 10% of January, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13862
23763
33664
43664
53763
63664
73664
83763
93862
103862
113862
123961
133961
144060
153961
164060
174060
184060
194060
204060
214060
224060
234060
244060
254060
264060
274159
284159
294159
304258
314258

Chance of precipitation in January

Any precipitationSnow

Ukiah gets around 7.2 in of rain and snow over 12.4 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 40% and peaks near 42% on the wettest days, and about 2 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
1388
2388
3398
4398
5407
6407
7406
8406
9406
10405
11405
12405
13405
14414
15414
16414
17425
18425
19425
20425
21425
22415
23416
24416
25406
26406
27396
28396
29386
30376
31366

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.

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 18 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 36 minutes over January. Sunrise moves from 7:37 AM to 7:28 AM, and sunset from 4:55 PM to 5:24 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.37:374:55
29.37:374:55
39.37:384:56
49.37:384:57
59.37:384:58
69.47:384:59
79.47:385:00
89.47:385:00
99.47:385:01
109.47:375:02
119.47:375:03
129.47:375:04
139.57:375:05
149.57:375:06
159.57:365:07
169.57:365:08
179.67:365:09
189.67:355:10
199.67:355:11
209.67:355:12
219.77:345:13
229.77:345:14
239.77:335:15
249.77:335:17
259.87:325:18
269.87:315:19
279.87:315:20
289.87:305:21
299.97:295:22
309.97:295:23
319.97:285:24

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 2.1 kWh/m².

For context, solar energy here swings from a low near 1.92 kWh/m² to a high of 8.22 kWh/m² in July across the year — January's 2.1 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.0Dim
22.0Dim
32.0Dim
42.0Dim
52.0Dim
62.0Dim
72.0Dim
82.0Dim
92.0Dim
102.0Dim
112.0Dim
122.0Moderate
132.0Moderate
142.0Moderate
152.1Moderate
162.1Moderate
172.1Moderate
182.1Moderate
192.1Moderate
202.2Moderate
212.2Moderate
222.2Moderate
232.3Moderate
242.3Moderate
252.3Moderate
262.4Moderate
272.4Moderate
282.5Moderate
292.5Moderate
302.5Moderate
312.6Moderate
Planning a trip in January

Hazard calendar for Ukiah

In seasonPeak

In January, Ukiah sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Ukiah's rainy season runs November–March, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is January a good time to visit Ukiah?

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

3.0
Sightseeing
11th-best month of the year
0.0
Beach & pool
12th-best month of the year

January is a weaker month for outdoor sightseeing in Ukiah.

What to pack for Ukiah in January

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

In January, Ukiah sees daytime highs around 54°F and nights near 37°F. Worth packing: a warm layer and rain gear. About 12 days see rain.

a warm layerrain gear

Sea temperature near Ukiah in January

The nearest coast averages about 53°F in January — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 29 mi away) is warmest in September at about 55°F and coldest in April near 52°F.

The water stays below 68°F all year — cool enough that most swimmers want a wetsuit.

50°52°54°56°JanFebMarAprMayJunJulAugSepOctNovDecbracing
Sea temperature (°F)Comfort
Jan53Bracing
Feb53Bracing
Mar53Bracing
Apr52Bracing
May52Bracing
Jun52Bracing
Jul53Bracing
Aug54Bracing
Sep55Bracing
Oct55Bracing
Nov55Bracing
Dec54Bracing

UV index in Ukiah in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 2. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ukiah peaks around July 10 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 2 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateLowJul 10UV 10Dec 15UV 2
UV index (midday)Level
Jan2Moderate
Feb3Moderate
Mar5Moderate
Apr6High
May9Very high
Jun10Very high
Jul10Extreme
Aug9Very high
Sep6High
Oct5Moderate
Nov2Moderate
Dec2Low

Air quality in Ukiah 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 Ukiah is worst in September — around 31 µg/m³ PM2.5 (moderate), about 5.8× the cleanest month (June, 5 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1031 µg/m³Jun 106 µg/m³
PM2.5 (µg/m³)Level
Jan6Good
Feb8Good
Mar9Good
Apr8Good
May6Good
Jun5Good
Jul14Moderate
Aug29Moderate
Sep31Moderate
Oct14Moderate
Nov8Good
Dec6Good
Location & terrain

Where is Ukiah?

Ukiah sits at 39.2°N, 123.2°W, 633 ft above sea level, in United States. The nearest listed city is Clearlake, 34 mi away.

Topography around Ukiah

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

Within 2 miles, the terrain around Ukiah has significant variations in elevation — a maximum elevation change of 1,765 ft around an average of 827 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,415 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 7,362 ft.

The land around Ukiah is covered by trees (51%), artificial surfaces (25%) and grassland (20%) within 2 miles, trees (72%) and grassland (24%) within 10 miles, and trees (59%) and water (21%) within 50 miles.

2 miles
1,765 ft
10 miles
3,415 ft
50 miles
7,362 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
January weather nearby: Clearlake 34 mi · Windsor 47 mi · Santa Rosa 56 mi · Rohnert Park 62 mi · Agua Caliente 69 mi · Petaluma 70 mi · Napa 77 mi · Novato 80 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 Ukiah (39.1502°, -123.2078°, elevation 633 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. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).