Bay Point weather in December

In December, Bay Point sees average daytime highs of 57°F and overnight lows near 43°F, with 3.3 in of rain across 8.6 wet days and about 9.4 hours of daylight. It is the 11th-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 59°F in the first days to 56°F by the end. The sky is clear or mostly clear about 34% of the time in December, and the air most often feels dry.

Daylight stretches from about 9 h 36 min at the start of December to 9 h 24 min by month's end. Set against the rest of the year, December is Bay Point's 10th-clearest and 10th-windiest month. For the whole year in context, see Bay Point's year-round climate.

Daytime high
57°
11th warmest
Overnight low
43°
2nd coldest
Rainfall
3.3 in
8.6 wet days
Daylight
9 h 24 min
7:23 AM – 4:45 PM
Cloud cover
58%
10th clearest
Wind
5 mph
10th windiest
Solar energy
2.14 kWh/m²
Travel score
4.3
out of 10

Bay Point is census designated place in California.

Density
1,123/km²
people per km²

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 59°F in the first days to 56°F by the end.

A typical December day in Bay Point reaches about 57°F in the afternoon and slips back to 43°F overnight — a 15°F spread between the day's warmth and the night's chill. On most days the high lands between 52°F and 63°F. Set against its neighbours, December runs about 7°F cooler than November and on par with January.

30°40°50°60°70°151015202531
Avg high (°F)Avg low (°F)
16044
26044
35944
45944
55944
65944
75844
85844
95843
105843
115843
125843
135743
145743
155743
165742
175742
185742
195742
205642
215642
225642
235642
245642
255642
265642
275642
285642
295642
305642
315642

Bay Point weather by month

How December compares with the rest of the year at a glance. December is the 11th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan57° / 42°3.78.99.74.2
Feb61° / 44°3.78.710.55.1
Mar65° / 47°2.88.311.76.3
Apr69° / 49°1.34.7137.4
May74° / 52°0.72.9148.5
Jun80° / 55°0.10.814.68.8
Jul82° / 57°0.00.214.48.8
Aug82° / 57°0.10.213.58.7
Sep81° / 56°0.10.412.38.7
Oct75° / 53°0.82.8118.6
Nov65° / 47°1.75.49.96.5
Dec57° / 43°3.38.69.44.3

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 13% of December, with mostly cloudy or overcast conditions the remaining 54%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15050
24852
34852
44753
54654
64555
74654
84555
94456
104555
114555
124555
134555
144555
154654
164753
174753
184852
194951
204951
214951
224852
234852
244951
254852
264753
274654
284654
294456
304456
314357

Chance of precipitation in December

Any precipitation

Bay Point gets around 3.3 in of rain over 8.6 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 28% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
126
227
328
428
529
629
730
830
930
1030
1130
1230
1330
1429
1529
1628
1728
1827
1927
2026
2126
2226
2326
2426
2526
2626
2726
2826
2926
3026
3127

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 97% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)
1973
2973
3973
4973
5964
6964
7964
8964
9964
10964
11973
12973
13973
14973
15973
16973
17982
18982
19982
20982
21982
22982
23982
24982
25982
26982
27982
28982
29982
30991
31991

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 9 h 36 min at the start of December to 9 h 24 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 7:11 AM to 7:29 AM, and sunset from 4:44 PM to 4:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
19.67:114:44
29.57:124:44
39.57:134:44
49.57:144:44
59.57:154:44
69.57:154:44
79.57:164:44
89.47:174:44
99.47:184:44
109.47:194:44
119.47:194:44
129.47:204:44
139.47:214:44
149.47:214:45
159.47:224:45
169.47:234:45
179.47:234:46
189.47:244:46
199.47:254:46
209.47:254:47
219.47:264:47
229.47:264:48
239.47:274:48
249.47:274:49
259.47:274:49
269.47:284:50
279.47:284:50
289.47:284:51
299.47:294:51
309.47:294:52
319.47:294:53

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.14 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 2.14 kWh/m² to a high of 8.05 kWh/m² in June across the year — December's 2.14 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.3Moderate
22.3Moderate
32.2Moderate
42.2Moderate
52.2Moderate
62.2Moderate
72.1Moderate
82.1Moderate
92.1Moderate
102.1Moderate
112.1Moderate
122.1Moderate
132.1Moderate
142.1Moderate
152.1Moderate
162.1Moderate
172.1Moderate
182.1Moderate
192.1Moderate
202.1Moderate
212.1Moderate
222.1Moderate
232.1Moderate
242.1Moderate
252.1Moderate
262.1Moderate
272.1Moderate
282.2Moderate
292.2Moderate
302.2Moderate
312.2Moderate
Planning a trip in December

Is December a good time to visit Bay Point?

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

4.3
Sightseeing
11th-best month of the year
0.1
Beach & pool
11th-best month of the year

December is a reasonable time to visit Bay Point for sightseeing.

What to pack for Bay Point in December

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

In December, Bay Point sees daytime highs around 57°F and nights near 43°F. Worth packing: a warm layer and rain gear. About 9 days see rain.

a warm layerrain gear

Sea temperature near Bay Point in December

The nearest coast averages about 54°F in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 38 mi away) is warmest in September at about 58°F and coldest in April near 53°F.

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

52°54°56°58°60°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°F)Comfort
Jan53Bracing
Feb53Bracing
Mar54Bracing
Apr53Bracing
May53Bracing
Jun54Bracing
Jul56Bracing
Aug58Bracing
Sep58Bracing
Oct57Bracing
Nov55Bracing
Dec54Bracing

UV index in Bay Point 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 Bay Point peaks around June 23 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 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 highHighModerateJun 23UV 10Dec 15UV 2
UV index (midday)Level
Jan2Moderate
Feb4Moderate
Mar4Moderate
Apr6High
May8Very high
Jun10Very high
Jul10Very high
Aug10Very high
Sep6High
Oct5High
Nov2Moderate
Dec2Low

Air quality in Bay Point 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 Bay Point is worst in September — around 29 µg/m³ PM2.5 (moderate), about 4.2× the cleanest month (June, 7 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateSep 1829 µg/m³Jun 127 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb13Moderate
Mar13Moderate
Apr10Good
May8Good
Jun7Good
Jul10Good
Aug25Moderate
Sep29Moderate
Oct27Moderate
Nov16Moderate
Dec12Good
Location & terrain

Where is Bay Point?

Bay Point sits at 38.0°N, 122.0°W, 89 ft above sea level, in United States. The nearest listed city is Pittsburg, 4.3 mi away.

Topography around Bay Point

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

Within 2 miles, the terrain around Bay Point has significant variations in elevation — a maximum elevation change of 906 ft around an average of 184 ft above sea level; within 10 miles, large variations in elevation — a maximum elevation change of 3,494 ft; within 50 miles, very significant variations in elevation — a maximum elevation change of 4,308 ft.

The land around Bay Point is covered by grassland (37%) and artificial surfaces (30%) within 2 miles, grassland (32%) within 10 miles, and grassland (30%) and trees (23%) within 50 miles.

2 miles
906 ft
10 miles
3,494 ft
50 miles
4,308 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetland
December weather nearby: Pittsburg 4.3 mi · Concord 5.0 mi · Pleasant Hill 8.1 mi · Antioch 8.7 mi · Martinez 9.3 mi · Walnut Creek 9.9 mi · Benicia 11 mi · Lafayette 13 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 Bay Point (38.0291°, -121.9616°, elevation 89 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).