Richland weather in December

In December, Richland sees average daytime highs of 41°F and overnight lows near 29°F, with 1.4 in of precipitation across 8.4 wet days and about 8.5 hours of daylight. It is the 12th-warmest and 1st-wettest month of the year here.

Highs ease over the month, from about 43°F in the first days to 39°F by the end. The sky is clear or mostly clear about 20% of the time in December, and the air most often feels dry.

Daylight stretches from about 8 h 42 min at the start of December to 8 h 30 min by month's end. Set against the rest of the year, December is Richland's 11th-clearest and 11th-windiest month. For the whole year in context, see Richland's year-round climate.

Daytime high
41°
12th warmest
Overnight low
29°
2nd coldest
Precipitation
1.4 in
8.4 wet days
Daylight
8 h 24 min
7:40 AM – 4:06 PM
Cloud cover
69%
11th clearest
Wind
5 mph
11th windiest
Solar energy
1.26 kWh/m²
Travel score
0.1
out of 10

Richland is city in Benton County, Washington, United States.

Density
495/km²
people per km²
Founded
1905

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 43°F in the first days to 39°F by the end.

A typical December day in Richland reaches about 41°F in the afternoon and slips back to 29°F overnight — a 12°F spread between the day's warmth and the night's chill. On most days the high lands between 30°F and 53°F. Set against its neighbours, December runs about 9°F cooler than November and on par with January.

20°30°40°50°60°151015202531
Avg high (°F)Avg low (°F)
14330
24330
34330
44230
54230
64230
74229
84229
94229
104129
114129
124129
134129
144129
154129
164129
174129
184029
194029
204029
214029
224029
234029
244028
254028
264028
274028
283928
293928
303928
313928

How December really feels in Richland

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.

Richland 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
Jan41° / 29°1.38.12.38.80.2
Feb48° / 32°0.96.21.3102.0
Mar58° / 38°0.95.90.411.64.6
Apr68° / 44°0.74.9013.36.9
May77° / 52°0.74.5014.77.6
Jun84° / 58°0.52.8015.56.6
Jul93° / 64°0.11015.23.9
Aug92° / 62°0.210144.5
Sep81° / 54°0.31.8012.37.7
Oct66° / 44°0.95010.76.7
Nov50° / 35°1.17.30.79.22.4
Dec41° / 29°1.48.42.48.50.1

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 12% of December, with mostly cloudy or overcast conditions the remaining 67%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23763
33763
43664
53565
63466
73466
83565
93367
103367
113367
123367
133169
143169
153169
163169
173169
183169
193169
203070
213169
223169
233169
243268
253268
263268
273268
283367
293367
303367
313367

Chance of precipitation in December

Any precipitationSnow

Richland gets around 1.4 in of rain and snow over 8.4 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 27% and peaks near 28% on the wettest days, and about 2 days bring snow.

0%10%20%30%40%151015202531
Rain chance (%)Snow chance (%)
1265
2266
3266
4276
5276
6276
7276
8276
9287
10287
11287
12287
13287
14287
15288
16288
17288
18278
19278
20278
21279
22279
23279
24279
252710
262710
272710
282710
292710
302711
312711

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 5 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
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 8 h 42 min at the start of December to 8 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over December. Sunrise moves from 7:26 AM to 7:47 AM, and sunset from 4:07 PM to 4:14 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
18.77:264:07
28.77:284:07
38.67:294:07
48.67:304:06
58.67:314:06
68.67:324:06
78.57:334:06
88.57:344:06
98.57:354:06
108.57:364:05
118.57:374:05
128.57:374:06
138.57:384:06
148.47:394:06
158.47:404:06
168.47:404:06
178.47:414:06
188.47:424:07
198.47:424:07
208.47:434:07
218.47:434:08
228.47:444:08
238.47:444:09
248.47:454:09
258.47:454:10
268.47:464:10
278.47:464:11
288.47:464:12
298.47:464:12
308.47:464:13
318.57:474:14

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 1.26 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 1.26 kWh/m² to a high of 7.85 kWh/m² in July across the year — December's 1.26 kWh/m² sits near the bottom.

00.511.52151015202531
Solar energy (kWh/m²)Level
11.4Dim
21.4Dim
31.3Dim
41.3Dim
51.3Dim
61.3Dim
71.3Dim
81.3Dim
91.3Dim
101.3Dim
111.2Dim
121.2Dim
131.2Dim
141.2Dim
151.2Dim
161.2Dim
171.2Dim
181.2Dim
191.2Dim
201.2Dim
211.2Dim
221.2Dim
231.2Dim
241.2Dim
251.3Dim
261.3Dim
271.3Dim
281.3Dim
291.3Dim
301.3Dim
311.3Dim
Planning a trip in December

Is December a good time to visit Richland?

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

0.1
Sightseeing
12th-best month of the year
0.0
Beach & pool
10th-best month of the year

December is a weaker month for outdoor sightseeing in Richland.

What to pack for Richland in December

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

In December, Richland sees daytime highs around 41°F and nights near 29°F. Pack a warm layer. Worth having: a heavy coat and rain gear. About 8 days see rain.

a warm layera heavy coatrain gear

UV index in Richland in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 1. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Richland peaks around July 16 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighHighVery highHighModerateLowJul 16UV 8Dec 17UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5Moderate
May7Very high
Jun6High
Jul8Very high
Aug6High
Sep5Moderate
Oct3Moderate
Nov1Low
Dec1Low

Air quality in Richland 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 Richland is worst in August — around 27 µg/m³ PM2.5 (moderate), about 3.1× the cleanest month (December, 9 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodAug 2026 µg/m³Dec 189 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar14Moderate
Apr11Good
May9Good
Jun10Good
Jul13Moderate
Aug27Moderate
Sep21Moderate
Oct12Moderate
Nov11Good
Dec9Good
Location & terrain

Where is Richland?

Richland sits at 46.3°N, 119.3°W, 384 ft above sea level, in United States. The nearest listed city is Tri-Cities, 5.0 mi away.

Topography around Richland

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

Within 2 miles, the terrain around Richland has only modest variations in elevation — a maximum elevation change of 223 ft around an average of 374 ft above sea level; within 10 miles, significant variations in elevation — a maximum elevation change of 1,450 ft; within 50 miles, large variations in elevation — a maximum elevation change of 3,894 ft.

The land around Richland is covered by artificial surfaces (39%), grassland (22%) and trees (20%) within 2 miles, grassland (45%) and cropland (25%) within 10 miles, and grassland (52%) and cropland (40%) within 50 miles.

2 miles
223 ft
10 miles
1,450 ft
50 miles
3,894 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Tri-Cities 5.0 mi · Kennewick 8.7 mi · Pasco 9.3 mi · Hermiston 31 mi · Sunnyside 35 mi · Walla Walla 48 mi · Pendleton 48 mi · Moses Lake 58 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 Richland (46.2857°, -119.2845°, elevation 384 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).