Santos weather in December

In December, Santos sees average daytime highs of 25°C and overnight lows near 23°C, with 179 mm of rain across 18.2 wet days and about 13.5 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs climb over the month, from about 24°C in the first days to 26°C by the end. The sky is clear or mostly clear about 19% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 13 h 24 min at the start of December to 13 h 30 min by month's end. Set against the rest of the year, December is Santos's 9th-clearest and 5th-windiest month. For the whole year in context, see Santos's year-round climate.

Daytime high
25°
4th warmest
Overnight low
23°
9th coldest
Rainfall
179 mm
18.2 wet days
Daylight
13 h 30 min
6:17 AM – 7:46 PM
Cloud cover
68%
9th clearest
Wind
12 km/h
5th windiest
Solar energy
6.1 kWh/m²
Travel score
5.4
out of 10
Air quality
Moderate
PM2.5 15 µg/m³ · 2016

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 24°C in the first days to 26°C by the end.

A typical December day in Santos reaches about 25°C in the afternoon and slips back to 23°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 23°C and 28°C. Set against its neighbours, December runs about 2°C warmer than November and about 1°C cooler than January.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12422
22422
32422
42422
52422
62522
72522
82522
92522
102522
112522
122523
132523
142523
152523
162523
172523
182523
192523
202623
212623
222623
232623
242623
252623
262623
272623
282623
292623
302624
312624

Santos weather by month

How December compares with the rest of the year at a glance. December is the 4th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 24°22620.913.34.9
Feb27° / 24°19917.412.85.1
Mar26° / 24°20719.512.25.3
Apr25° / 22°12713.411.56.4
May23° / 20°12512.710.96.5
Jun22° / 19°971010.56.8
Jul21° / 18°1151010.76.8
Aug21° / 18°9410.211.26.6
Sep22° / 19°14214.311.95.9
Oct23° / 20°15916.212.65.6
Nov24° / 21°17416.813.25.7
Dec25° / 23°17918.213.55.4

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 19% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 17% of December, with mostly cloudy or overcast conditions the remaining 64%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23664
33565
43565
53565
63466
73466
83466
93466
103466
113565
123565
133565
143565
153664
163763
173763
183763
193862
203862
213961
223961
233961
243862
253862
263862
273763
283565
293565
303466
313466

Chance of precipitation in December

Any precipitation

Santos gets around 179 mm of rain over 18.2 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 59% and peaks near 62% on the wettest days.

0%20%40%60%151015202531
Rain chance (%)
156
256
357
458
558
659
759
859
960
1060
1160
1260
1360
1460
1560
1660
1760
1860
1959
2059
2159
2258
2358
2458
2559
2659
2760
2861
2961
3062
3162

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the oppressive band about 56% of days. Sticky, muggy-or-worse air turns up on roughly 92% of them.

0%25%50%75%100%151015202531
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
131342411
221242431
321241441
421140461
521139471
611138481
711137501
811036521
911035531
1011034532
111934542
120933562
130832573
140831583
150830593
160729604
170728605
180727615
190727606
200726607
210625627
220625618
230624619
240523639
2505236210
2605226310
2704226311
2804216312
2904216312
3004216213
3104216114

Wind in December

Winds average 12 km/h in December.

Across December, daily wind ranges from about 11 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812calm
1912calm
2012calm
2112calm
2212calm
2312calm
2412calm
2512calm
2612calm
2712calm
2811calm
2911calm
3011calm
3111calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 13 h 24 min at the start of December to 13 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 6 minutes over December. Sunrise moves from 6:14 AM to 6:25 AM, and sunset from 7:36 PM to 7:52 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
113.46:147:36
213.46:147:37
313.46:147:38
413.46:147:38
513.46:147:39
613.46:157:40
713.46:157:40
813.46:157:41
913.46:157:42
1013.46:157:42
1113.56:167:43
1213.56:167:43
1313.56:167:44
1413.56:177:45
1513.56:177:45
1613.56:177:46
1713.56:187:46
1813.56:187:47
1913.56:197:47
2013.56:197:48
2113.56:197:48
2213.56:207:49
2313.56:207:49
2413.56:217:50
2513.56:217:50
2613.56:227:51
2713.56:227:51
2813.56:237:51
2913.56:247:52
3013.56:247:52
3113.56:257:52

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 6.1 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 3.16 kWh/m² to a high of 6.1 kWh/m² in December across the year — December's 6.1 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.0Intense
26.0Intense
36.0Intense
46.0Intense
56.0Intense
66.0Intense
76.0Intense
86.0Intense
96.0Intense
106.0Intense
116.0Intense
126.0Intense
136.0Intense
146.0Intense
156.0Intense
166.1Intense
176.1Intense
186.1Intense
196.1Intense
206.1Intense
216.1Intense
226.1Intense
236.1Intense
246.1Intense
256.1Intense
266.1Intense
276.1Intense
286.1Intense
296.1Intense
306.1Intense
316.0Intense
Planning a trip in December

Is December a good time to visit Santos?

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

5.4
Sightseeing
9th-best month of the year
5.0
Beach & pool
5th-best month of the year

December is a reasonable time to visit Santos for sightseeing.

What to pack for Santos in December

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

In December, Santos sees daytime highs around 25°C and nights near 23°C. Pack rain gear and sun protection. Worth having: light clothes. About 18 days see rain.

rain gearsun protectionlight clothes

Sea temperature near Santos in December

The nearest coast averages about 25°C 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 19 km away) is warmest in February at about 27°C and coldest in August near 20°C.

The water stays above 20°C all year — warm enough for a swim any month.

20°25°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr26Warm
May24Refreshing
Jun22Refreshing
Jul21Refreshing
Aug20Refreshing
Sep21Refreshing
Oct22Refreshing
Nov23Refreshing
Dec25Warm

UV index in Santos in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Santos peaks around February 10 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 at about 5 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighHighVery highExtremeFeb 10UV 14Jul 12UV 5
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar10Very high
Apr8Very high
May6High
Jun5High
Jul5Moderate
Aug7High
Sep7Very high
Oct10Extreme
Nov12Extreme
Dec13Extreme

Air quality in Santos 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 Santos is worst in July — around 23 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (February, 11 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Santos's WHO annual average of 15 µg/m³.

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1422 µg/m³Feb 1311 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb11Good
Mar11Good
Apr12Moderate
May16Moderate
Jun22Moderate
Jul23Moderate
Aug21Moderate
Sep18Moderate
Oct13Moderate
Nov11Good
Dec11Good
Location & terrain

Where is Santos?

Santos sits at 24.0°S, 46.3°W, 12 m above sea level, in Brazil. The nearest listed city is São Vicente, 6.0 km away.

Topography around Santos

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Santos.

Within 3 km, the terrain around Santos has only modest variations in elevation — a maximum elevation change of 207 m around an average of 24 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 998 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,434 m.

The land around Santos is covered by artificial surfaces (54%) and water (27%) within 3 km, water (39%) and trees (33%) within 16 km, and water (47%) and trees (38%) within 80 km.

3 km
207 m
16 km
998 m
80 km
1,434 m
treesgrasslandartificial surfacesbare terrainwaterwetlandmangroves
December weather nearby: São Vicente 6.0 km · Guarujá 9.0 km · Praia Grande 9.0 km · Cubatão 12 km · Bertioga 23 km · Rio Grande da Serra 25 km · Ribeirão Pires 29 km · Mongaguá 33 km

Brazil travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / N
127 / 220 V · 60 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$10,713
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
89%
of population, 2024
Homicide rate
19.3
per 100k, 2023
Road deaths
16
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 482
Religion
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Santos (-23.9608°, -46.3336°, elevation 12 m), 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).