São Tomé weather in December

In December, São Tomé sees average daytime highs of 27°C and overnight lows near 25°C, with 174 mm of rain across 26.1 wet days and about 12 hours of daylight. It is the 6th-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 11% of the time in December, and the air most often feels oppressive.

Daylight stretches from about 12 hours at the start of December to 12 hours by month's end. Set against the rest of the year, December is São Tomé's 5th-clearest and 8th-windiest month. For the whole year in context, see São Tomé's year-round climate.

Daytime high
27°
6th warmest
Overnight low
25°
7th coldest
Rainfall
174 mm
26.1 wet days
Daylight
12 hours
5:30 AM – 5:29 PM
Cloud cover
72%
5th clearest
Wind
13 km/h
8th windiest
Solar energy
4.89 kWh/m²
Travel score
4.1
out of 10

São Tomé is capital city of São Tomé and Príncipe.

Density
3,135/km²
people per km²
Founded
1485

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 27°C through the month.

A typical December day in São Tomé reaches about 27°C in the afternoon and slips back to 25°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 27°C. Set against its neighbours, December runs on par with November and on par with January.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12725
22725
32725
42725
52725
62725
72725
82725
92725
102725
112725
122725
132725
142725
152725
162725
172725
182725
192725
202725
212725
222725
232725
242725
252725
262725
272725
282725
292725
302725
312725

São Tomé weather by month

How December compares with the rest of the year at a glance. December is the 6th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 26°13523.6124.3
Feb28° / 26°11319.3124.6
Mar28° / 26°13320.5124.4
Apr28° / 26°13018.7124.8
May27° / 26°11917125.3
Jun25° / 24°234127.5
Jul24° / 24°82128.0
Aug24° / 24°142.6127.9
Sep25° / 24°467.8126.9
Oct26° / 25°15221.5124.9
Nov26° / 25°21025.7124.1
Dec27° / 25°17426.1124.1

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 21% of December, with mostly cloudy or overcast conditions the remaining 67%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13367
23367
33367
43367
53367
63466
73466
83466
93466
103466
113565
123565
133565
143565
153565
163466
173466
183466
193466
203367
213367
223268
233268
243169
253070
263070
272971
282971
292971
302872
312872

Chance of precipitation in December

Any precipitation

São Tomé gets around 174 mm of rain over 26.1 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 84% and peaks near 86% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
186
286
386
486
585
685
785
884
984
1084
1183
1283
1383
1483
1583
1683
1783
1883
1983
2083
2184
2284
2384
2484
2584
2684
2784
2884
2984
3084
3184

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 99% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Oppressive (%)Miserable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10991
11991
12991
13991
14991
15991
16991
17991
18991
19991
20991
21991
22991
23991
24991
25991
26991
27991
28991
29991
30991
31991

Wind in December

Winds average 13 km/h in December.

Across December, daily wind ranges from about 12 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
114light breeze
214light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze
3112light breeze

Sunrise & sunset in December

DaylightNight

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

Days grow by about 0 minutes over December. Sunrise moves from 5:23 AM to 5:37 AM, and sunset from 5:22 PM to 5:36 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.05:235:22
212.05:245:23
312.05:245:23
412.05:255:23
512.05:255:24
612.05:255:24
712.05:265:25
812.05:265:25
912.05:275:26
1012.05:275:26
1112.05:285:26
1212.05:285:27
1312.05:285:27
1412.05:295:28
1512.05:295:28
1612.05:305:29
1712.05:305:29
1812.05:315:30
1912.05:315:30
2012.05:325:31
2112.05:325:31
2212.05:335:31
2312.05:335:32
2412.05:345:32
2512.05:345:33
2612.05:355:33
2712.05:355:34
2812.05:355:34
2912.05:365:35
3012.05:365:35
3112.05:375:36

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.89 kWh/m² — the year's lowest.

For context, solar energy here swings from a low near 4.89 kWh/m² to a high of 5.48 kWh/m² in March across the year — December's 4.89 kWh/m² sits near the bottom.

024151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.9Bright
44.9Bright
54.9Bright
64.9Bright
74.9Bright
84.9Bright
94.9Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
144.9Bright
154.9Bright
164.9Bright
174.9Bright
184.9Bright
194.9Bright
204.9Bright
214.9Bright
224.9Bright
234.9Bright
244.9Bright
254.9Bright
264.9Bright
274.9Bright
284.9Bright
294.9Bright
304.9Bright
315.0Bright
Planning a trip in December

Hazard calendar for São Tomé

In seasonPeak

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

São Tomé's rainy season runs October–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 São Tomé?

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

4.1
Sightseeing
11th-best month of the year
4.1
Beach & pool
11th-best month of the year

December is a reasonable time to visit São Tomé for sightseeing.

What to pack for São Tomé in December

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

In December, São Tomé sees daytime highs around 27°C and nights near 25°C. Pack rain gear. Worth having: light clothes and sun protection. About 26 days see rain.

rain gearlight clothessun protection

Sea temperature near São Tomé in December

The nearest coast averages about 28°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea offshore is warmest in March at about 29°C and coldest in August near 26°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May28Tropical
Jun27Warm
Jul26Warm
Aug26Warm
Sep26Warm
Oct27Warm
Nov28Warm
Dec28Tropical

UV index in São Tomé in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in São Tomé peaks around March 21 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near August 12 at about 9 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 21UV 14Aug 12UV 9
UV index (midday)Level
Jan11Extreme
Feb12Extreme
Mar14Extreme
Apr13Extreme
May11Extreme
Jun9Very high
Jul9Very high
Aug8Very high
Sep12Extreme
Oct13Extreme
Nov12Extreme
Dec11Extreme

Air quality in São Tomé 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 São Tomé is worst in February — around 24 µg/m³ PM2.5 (moderate), about 4.6× the cleanest month (October, 5 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateGoodModerateFeb 1023 µg/m³Oct 175 µg/m³
PM2.5 (µg/m³)Level
Jan22Moderate
Feb24Moderate
Mar15Moderate
Apr11Good
May12Moderate
Jun16Moderate
Jul17Moderate
Aug13Moderate
Sep8Good
Oct5Good
Nov8Good
Dec15Moderate
Location & terrain

Where is São Tomé?

São Tomé sits at 0.3°N, 6.7°E, 140 m above sea level, in Sao Tome and Principe. The nearest listed city is Port-Gentil, 257 km away.

Topography around São Tomé

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

Within 3 km, the terrain around São Tomé has only modest variations in elevation — a maximum elevation change of 111 m around an average of 23 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,396 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,938 m.

The land around São Tomé is covered by water (43%), trees (31%) and artificial surfaces (24%) within 3 km, water (60%) and trees (36%) within 16 km, and water (90%) within 80 km.

3 km
111 m
16 km
1,396 m
80 km
1,938 m
treesgrasslandartificial surfaceswater
December weather nearby: Port-Gentil 257 km · Akanda 291 km · Libreville 303 km · Owendo 309 km · Ntoum 337 km · Bata 378 km · Lambaréné 407 km · Malabo 443 km

Sao Tome and Principe travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type C / F
220 V · 50 Hz
Prices
≈ 61% of US
price level, 2025
GDP per capita
$4,084
2025
Safe drinking water
37%
of population, 2024
Homicide rate
3.2
per 100k, 2011
Road deaths
27.9
per 100k/yr, 2019
Income group
Lower middle
World Bank
Religion
Catholic 56%none 21%other 6%Adventist 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 São Tomé (0.3376°, 6.7299°, elevation 140 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).