Susanville weather in December

In December, Susanville sees average daytime highs of 37°F and overnight lows near 22°F, with 3.8 in of precipitation across 10.5 wet days and about 9.2 hours of daylight. It is the 12th-warmest and 1st-wettest month of the year here.

Highs ease over the month, from about 39°F in the first days to 36°F by the end. The sky is clear or mostly clear about 28% of the time in December, and the air most often feels dry.

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

Daytime high
37°
12th warmest
Overnight low
22°
1st coldest
Precipitation
3.8 in
10.5 wet days
Daylight
9 h 06 min
7:25 AM – 4:33 PM
Cloud cover
65%
12th clearest
Wind
5 mph
7th windiest
Solar energy
2.08 kWh/m²
Travel score
0.0
out of 10

Susanville is city in and county seat of Lassen County, California, United States.

Density
733/km²
people per km²
Founded
1900

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 39°F in the first days to 36°F by the end.

A typical December day in Susanville reaches about 37°F in the afternoon and slips back to 22°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 28°F and 44°F. Set against its neighbours, December runs about 10°F cooler than November and on par with January.

10°20°30°40°50°151015202531
Avg high (°F)Avg low (°F)
14025
24024
33924
43924
53924
63824
73823
83823
93823
103723
113722
123722
133722
143722
153622
163621
173621
183621
193621
203621
213621
223620
233620
243620
253620
263620
273620
283620
293621
303621
313621

How December really feels in Susanville

Once humidity and wind are folded in, December 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 December is cold — wind chill drags the overnight "feels like" below the raw low.

Susanville weather by month

How December compares with the rest of the year at a glance. December is the 12th-warmest and 1st-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan38° / 22°3.59.69.19.40.0
Feb41° / 24°3.39.69.110.40.1
Mar46° / 28°3.210.59.211.71.3
Apr53° / 32°2.09.46133.2
May64° / 40°1.98.51.814.26.0
Jun75° / 48°0.94.80.314.88.0
Jul85° / 55°0.42.7014.66.9
Aug84° / 54°0.42.6013.67.3
Sep75° / 48°0.630.112.38.5
Oct62° / 39°1.14.51.210.96.4
Nov47° / 29°2.27.55.59.81.6
Dec37° / 22°3.810.59.69.20.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in December, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 13% of December, with mostly cloudy or overcast conditions the remaining 60%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24357
34258
44159
54159
64060
73961
84060
93961
103961
113961
123862
133961
143961
154060
164060
174159
184060
194159
204159
214159
224159
234159
244159
254159
264159
274159
284159
294159
304060
313961

Chance of precipitation in December

Any precipitationSnow

Susanville gets around 3.8 in of rain and snow over 10.5 wet days in December, the wettest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable precipitation averages around 33% and peaks near 37% on the wettest days, and about 10 days bring snow.

0%10%20%30%40%50%151015202531
Rain chance (%)Snow chance (%)
13226
23327
33328
43429
53530
63531
73631
83632
93733
103733
113733
123634
133634
143633
153533
163533
173432
183332
193331
203231
213231
223130
233130
243029
253029
263029
272929
282928
292928
302929
313029

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December 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 December

Winds average 5 mph in December.

Across December, daily wind ranges from about 4 mph on the calmest days to 5 mph at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (mph)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 9 h 18 min at the start of December to 9 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 7:13 AM to 7:31 AM, and sunset from 4:32 PM to 4:40 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.37:134:32
29.37:144:32
39.37:144:32
49.37:154:32
59.37:164:32
69.27:174:31
79.27:184:31
89.27:194:31
99.27:204:31
109.27:214:32
119.27:214:32
129.27:224:32
139.27:234:32
149.17:244:32
159.17:244:32
169.17:254:33
179.17:264:33
189.17:264:33
199.17:274:34
209.17:274:34
219.17:284:34
229.17:284:35
239.17:294:35
249.17:294:36
259.17:304:36
269.17:304:37
279.17:304:38
289.17:314:38
299.17:314:39
309.17:314:40
319.27:314:40

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.08 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.08 kWh/m² to a high of 8.22 kWh/m² in July across the year — December's 2.08 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.2Moderate
22.1Moderate
32.1Moderate
42.1Moderate
52.1Moderate
62.1Moderate
72.1Moderate
82.0Moderate
92.0Moderate
102.0Moderate
112.0Moderate
122.0Moderate
132.0Moderate
142.0Moderate
152.0Moderate
162.0Moderate
172.0Moderate
182.0Moderate
192.0Moderate
202.0Moderate
212.1Moderate
222.1Moderate
232.1Moderate
242.1Moderate
252.1Moderate
262.1Moderate
272.1Moderate
282.1Moderate
292.2Moderate
302.2Moderate
312.2Moderate
Planning a trip in December

Hazard calendar for Susanville

In seasonPeak

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

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

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

Is December a good time to visit Susanville?

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

0.0
Sightseeing
11th-best month of the year
0.0
Beach & pool
9th-best month of the year

December is a weaker month for outdoor sightseeing in Susanville.

What to pack for Susanville in December

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

In December, Susanville sees daytime highs around 37°F and nights near 22°F. Pack a warm layer and a heavy coat. Worth having: rain gear. About 11 days see rain.

a warm layera heavy coatrain gear

UV index in Susanville in December

LowModerateHighVery highExtreme

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

Under clear skies, the midday UV index in Susanville peaks around June 23 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 13 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 23UV 11Dec 13UV 2
UV index (midday)Level
Jan3Moderate
Feb4Moderate
Mar5High
Apr7Very high
May9Very high
Jun11Extreme
Jul11Extreme
Aug9Very high
Sep6High
Oct5Moderate
Nov2Moderate
Dec2Moderate

Air quality in Susanville in December

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Susanville is worst in August — around 148 µg/m³ PM2.5 (unhealthy), about 33.7× the cleanest month (December, 4 µg/m³).

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

0306090120150JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateUnhealthyGoodAug 16136 µg/m³Dec 195 µg/m³
PM2.5 (µg/m³)Level
Jan5Good
Feb6Good
Mar8Good
Apr9Good
May8Good
Jun7Good
Jul55Poor
Aug148Unhealthy
Sep45Poor
Oct8Good
Nov6Good
Dec4Good
Location & terrain

Where is Susanville?

Susanville sits at 40.4°N, 120.7°W, 4,186 ft above sea level, in United States. The nearest listed city is Paradise, 68 mi away.

Topography around Susanville

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

Within 2 miles, the terrain around Susanville has only modest variations in elevation — a maximum elevation change of 735 ft around an average of 4,308 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,652 ft; within 50 miles, extreme variations in elevation — a maximum elevation change of 8,543 ft.

The land around Susanville is covered by grassland (58%) and trees (22%) within 2 miles, trees (50%) and grassland (45%) within 10 miles, and trees (50%) and grassland (40%) within 50 miles.

2 miles
735 ft
10 miles
3,652 ft
50 miles
8,543 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Paradise 68 mi · Spanish Springs 73 mi · Sun Valley 73 mi · Reno 76 mi · Sparks 77 mi · Chico 79 mi · Oroville 79 mi · Truckee 79 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 Susanville (40.4163°, -120.653°, elevation 4,186 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).