São Tomé climate
São Tomé (Sao Tome and Principe) has a tropical savanna (dry summer) climate (Köppen As). The average temperature over the year is 26 °C78 °F, and about 1,251 mm49 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
São Tomé climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin |
|---|---|---|---|---|
| Jan | 2780 | 2679 | 2680 | 1295.1 |
| Feb | 2781 | 2680 | 2780 | 1194.7 |
| Mar | 2781 | 2780 | 2781 | 1676.6 |
| Apr | 2781 | 2780 | 2780 | 1766.9 |
| May | 2780 | 2679 | 2679 | 1275.0 |
| Jun | 2577 | 2476 | 2576 | 441.7 |
| Jul | 2476 | 2374 | 2475 | 220.9 |
| Aug | 2576 | 2475 | 2475 | 200.8 |
| Sep | 2578 | 2476 | 2577 | 411.6 |
| Oct | 2679 | 2577 | 2678 | 1144.5 |
| Nov | 2679 | 2578 | 2678 | 1586.2 |
| Dec | 2679 | 2678 | 2679 | 1345.3 |
| Year | 2781 | 2374 | 2678 | 1,25149 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 83% | 73% | 4.5 | 12:06 |
| Feb | 83% | 76% | 4.6 | 12:06 |
| Mar | 83% | 78% | 4.7 | 12:07 |
| Apr | 83% | 78% | 4.6 | 12:07 |
| May | 85% | 74% | 4.5 | 12:08 |
| Jun | 83% | 71% | 4.5 | 12:08 |
| Jul | 82% | 75% | 4.3 | 12:08 |
| Aug | 82% | 76% | 4.5 | 12:08 |
| Sep | 82% | 77% | 4.8 | 12:07 |
| Oct | 83% | 77% | 4.6 | 12:06 |
| Nov | 85% | 74% | 4.4 | 12:06 |
| Dec | 84% | 72% | 4.4 | 12:06 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of São Tomé is like
The warmest month is March, with an average high of 27 °C81 °F and a low of 27 °C80 °F. The coldest is July, when highs average 24 °C76 °F and lows 23 °C74 °F. Seasonal differences are small — just 3.2 °C5.7 °F between the warmest and the coolest month.
It is wet, with about 1,251 mm49 in of precipitation per year. The wettest three-month stretch is March–May, which brings 38% of the annual total. The wettest month is April (176 mm6.9 in), the driest is August (20 mm0.8 in).
Relative humidity ranges from 82% in August to 85% in November. The clearest skies (lowest average cloud amount, 71%) are typical of June. Average wind speed near the ground ranges from 11 km/h (7 mph) in January to 16 km/h (10 mph) in June.
Best time to visit São Tomé
Based on these averages, the most comfortable months for sightseeing and outdoor activities are June–September: average highs of 24 °C76 °F to 25 °C78 °F with 20 mm0.8 in to 44 mm1.7 in of precipitation per month.
The most challenging month is April, which is very wet (176 mm6.9 in) and humid (83% relative humidity).
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for São Tomé
- Wetter months (October–May) — highs 2679 to 27 °C81 °F, lows 2577 to 27 °C80 °F, about 140 mm5.5 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an umbrella or light rain jacket.
- Drier months (June–September) — highs 2476 to 25 °C78 °F, lows 2374 to 24 °C76 °F, about 32 mm1.3 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses.
How São Tomé compares
Compared with Port-Gentil, about 257 km to the southeast, São Tomé is on average 0.4 °C0.8 °F cooler and receives 38% less precipitation (1,251 mm49 in vs 2,017 mm79 in). The difference is largest in March (0.8 °C1.4 °F cooler).
Places in other countries with the most similar temperature and rainfall pattern: Cali (Colombia, As), Tumaco (Colombia, As) and Neiva (Colombia, As).
Nearby places
- Port-Gentil 257 km · 26 °C79 °F · 2,017 mm79 in
- Libreville 303 km · 26 °C79 °F · 2,315 mm91 in
- Bata 378 km · 26 °C79 °F · 2,412 mm95 in
- Malabo 443 km · 27 °C81 °F · 2,736 mm108 in
- Ciudad de la Paz 476 km · 24 °C75 °F · 1,979 mm78 in
- Ogbia 486 km · 26 °C79 °F · 2,507 mm99 in
- Buguma 489 km · 26 °C79 °F · 2,520 mm99 in
- Okrika 491 km · 26 °C79 °F · 2,520 mm99 in
Frequently asked questions
What is the warmest month in São Tomé?
March is the warmest month in São Tomé, with an average high of 27 °C (81 °F) and an average low of 27 °C (80 °F).
What is the coldest month in São Tomé?
July is the coldest month, with an average high of 24 °C (76 °F) and an average low of 23 °C (74 °F).
When does it rain the most in São Tomé?
April is the wettest month with about 176 mm (6.9 in) of precipitation; August is the driest with about 20 mm (0.8 in).
What is the best time to visit São Tomé?
Judging by long-term averages, the most comfortable months are June–September.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 29 m, while São Tomé lies at about 140 m. Temperatures on this page were therefore adjusted by −0.7 °C1.3 °F using the standard lapse rate of 6.5 °C per 1,000 m.