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Contents
- The climate of São Tomé
- The best time to visit São Tomé
- The worst time to visit São Tomé
- Spring weather in São Tomé
- Summer weather in São Tomé
- Autumn weather in São Tomé
- Winter weather in São Tomé
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average humidity
- Average rainfall
- Average rainfall days
- Average sea temperature
- Average daylight
- Average sunshine
- Average UV index
Clear blue water crashing on the big shore rocks on the beach in São Tomé, São Tomé and Principe
Climate and monthly weather forecast
The climate of São Tomé
São Tomé, positioned in the Gulf of Guinea just off the western coast of Africa, endures conditions indicative of a Tropical wet and dry climate. This climate, identified by the Köppen climate classification as 'As', subjects the citizens to a highly varied seasonal pattern. Here temperatures hover consistently throughout the year, with a scant divergence between high and low values. Whereas average high temperatures oscillate from 27.3°C (81.1°F) to 30.2°C (86.4°F), lows fluctuate modestly from 20.4°C (68.7°F) to 22.6°C (72.7°F). Ample sunshine hours insignificantly change from 3.7 hours to 5.5 hours across the year, a consistency owed to the city's close proximity to the equator.
Rainfall, on contrary, varies significantly throughout the year, implying a distinctive wet and dry season. A steep drop in precipitation occurs towards the middle of the year, as June receives 19mm (0.75") and July barely notices any, while in the months of March and April, São Tomé witnesses heavy showers amounting to 131mm (5.16") and 122mm (4.8") respectively. The pronounced shift in rainfall also impacts humidity, falling from 85% in the wet months to 77% during the drier parts of the year. Noteworthy is the sea temperature which remains relatively stable throughout the year, between 25°C (77°F) and 29°C (84.2°F), reinforcing the tropical weather traits of São Tomé.
Rainfall, on contrary, varies significantly throughout the year, implying a distinctive wet and dry season. A steep drop in precipitation occurs towards the middle of the year, as June receives 19mm (0.75") and July barely notices any, while in the months of March and April, São Tomé witnesses heavy showers amounting to 131mm (5.16") and 122mm (4.8") respectively. The pronounced shift in rainfall also impacts humidity, falling from 85% in the wet months to 77% during the drier parts of the year. Noteworthy is the sea temperature which remains relatively stable throughout the year, between 25°C (77°F) and 29°C (84.2°F), reinforcing the tropical weather traits of São Tomé.
The best time to visit São Tomé
For those preferring a drier and less humid getaway, the midway through the year, from June to August is an opportune period to visit São Tomé. Despite the diminished rainfall, humidity dips to a bearable 77-79%, while sea temperatures stay relatively warm, ranging from 25°C (77°F) to 26°C (78.8°F). Sunshine hours are marginally higher, nearing 5.2 to 5.5 hours, allowing a satisfying exploration of the city's stunning landscapes.
The worst time to visit São Tomé
Potential visitors interested in dry and less humid conditions might wish to avoid the first few months of the year. March and April are particularly soggy with rain showers reaching up to 131mm (5.16") and 122mm (4.8") respectively, accompanied by relative humidity soaring up to as high as 83-85%. The UV index is at its peak at 12, making it necessary to take ample sun protection measures during these months.
Spring weather in São Tomé
Considering the city's geographical location, traditional seasonal terminology might not precisely define the weather patterns. Yet, during the months of March, April, and May, relatively higher humidity levels from 83% to 84%, coupled with considerable rainfall averaging from 122mm (4.8") to 113mm (4.45"), make these months similar to the typical characteristics of Spring in other parts of the world. The temperatures remain balmy with highs ranging from 30.1°C (86.2°F) to 29.3°C (84.7°F) and lows between 22.6°C (72.7°F) to 22.6°C (72.7°F).
Summer weather in São Tomé
In the months synonymous with summer, namely June, July, and August, the humidity levels reduce to about 79% to 77%. The rainfall drops significantly, amounting to only as much as 19mm (0.75") in June and nearly negligible levels of 0mm (0") to 1mm (0.04") from July to August. The temperatures remain fairly consistent from June to August with highs varying between 28°C (82.4°F) to 27.7°C (81.9°F) and lows from 21.4°C (70.5°F) to 20.5°C (68.9°F).
Autumn weather in São Tomé
September, October, and November witness a significant rise in rainfall from 17mm (0.67") to 110mm (4.33"). The humidity levels rise again, varying from 79% to 82% which mirrors the climate change in Autumn. The high temperatures fluctuate between 28.6°C (83.5°F) and 29°C (84.2°F), while the low temperatures remain in the range of 21.3°C (70.3°F) to 22°C (71.6°F).
Winter weather in São Tomé
In the closing months of December, January, and February, typically signs of Winter in non-tropical locations, the island sees a return of regular rainfall, hovering from 99mm (3.9") to 108mm (4.25"). High temperatures continue to hover around the 29°C (84.2°F) mark, and lows keep steady between 22°C (71.6°F) to 22.4°C (72.3°F). Humidity levels peak during these months, reinforcing the beginnings of rainfall trends similar to the start of the year with an index of 85%.
Weather in January
January commences the year with balmy weather in São Tomé, São Tomé and Príncipe. The temperature flexes between 22.4°C (72.3°F) at its chilliest and 29.4°C (84.9°F) when it reaches its zenith. This serves as an introductory phase to the climatic journey of the year. Weather in January »
Weather in February
February carries the temperature dynamics of January into the second month, offering a predictability in weather conditions. The difference in temperature between the coolest and hottest moments fluctuates from 22.5°C (72.5°F) to 29.9°C (85.8°F). Weather in February »
Weather in March
As São Tomé steps into March, fluctuations in weather conditions start creeping in. The spectrum of temperature expands from 22.6°C (72.7°F) to 30.2°C (86.4°F) hinting at the upcoming summer months. Rainfall records a significant increase, earning the distinction of being the wettest month. Weather in March »
Weather in April
The weather becomes a mixed bag as April approaches. The temperature range remains static from 22.6°C (72.7°F) to 30.1°C (86.2°F) compared to March and something more distinct is noticeable. Despite the constant rainfall from the preceding month, the overall precipitation count lowers slightly. Weather in April »
Weather in May
May witnesses a decline in the mercury levels. When juxtaposing it with April, the month shows a downshift while the mounting rainfall provides relief. The overall temperature decreases slightly, settling within the neighbourhood of the earlier spells. Weather in May »
Weather in June
Transitioning into June, São Tomé encounters the force of nature in its full swing. With the largest temperature drop of the year, the temperature ranges from 21.4°C (70.5°F) to 28°C (82.4°F), which is noticeable but not severe. Weather in June »
Weather in July
July, the middle of the year, reflects a consolidation of temperature variations. The lowest temperature index of the year records between 20.4°C (68.7°F) and 27.3°C (81.1°F). While São Tomé remains warm, this month exhibits a critical shift with respect to the preceding months. Weather in July »
Weather in August
August, sails in like the breath of fresh air. Significant changes are marked with a rise in temperature from 20.5°C (68.9°F) to 27.7°C (81.9°F), and a minor escalation in rainfall. Comparatively, August lacks the clarity of the weather seen earlier in the year, indicating the upcoming shift in the seasonal cycle. Weather in August »
Weather in September
September is where variations start to show up in São Tomé weather. With a slight increase in temperature range from 21.3°C (70.3°F) to 28.6°C (83.5°F) compared to August, the dynamism becomes more palpable. The relative humidity sees an almost imperceptible increase, coupled with occasional drizzle. Weather in September »
Weather in October
October marks the return of warmer days in São Tomé. A gradual rise in temperature from 21.8°C (71.2°F) to 28.7°C (83.7°F) ushers in a change of season. As the year advances, rising temperatures play a symphony with the tropical landscape of this island nation. Weather in October »
Weather in November
November paints a vivid picture of fluctuating weather patterns in the archipelagic nation. The span of temperature swings between 22°C (71.6°F) when it's cooled down and accelerates to 29°C (84.2°F), providing a harmonious blend of pleasant and warm climates. Weather in November »
Weather in December
December brings the yearly climate cycle full circle in São Tomé. It a gradual escalation at the mercury’s scale, the temperature revolves between 22.1°C (71.8°F) and 29.1°C (84.4°F). The weather of December recalls the aura of January, offering a pleasant summation to the climatic journey of the year. Weather in December »
Updated: Aug 31, 2024
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the most humid month in São Tomé?
The months with the highest humidity are January, November and December, with an average relative humidity of 85%.
How many days does it rain in São Tomé?
In São Tomé, during the entire year, the rain falls for 94 days and collects up to 885mm (34.84") of precipitation.
What are the months with the highest UV index?
The months with the highest UV index are January through May, August through December, with an average maximum UV index of 12.
When is the sea warmest?
February through April, with an average sea temperature of 29°C (84.2°F), are months with the warmest seawater.
What is the hottest time of year?
In São Tomé, March is known for its average highest temperatures, reaching a high of 30.2°C (86.4°F) and a low of 22.6°C (72.7°F).
What is the rainiest month?
March is the month with the most rainfall. Rain falls for 12 days and accumulates 131mm (5.16") of precipitation.
When are the longest days?
June has the longest days of the year, with an average of 12h and 6min of daylight.
What month has the most sunshine?
The month with the most sunshine is June, with an average of 5.5h of sunshine.
What is the coldest month?
São Tomé's coldest temperatures are experienced in July, with average high temperatures of 27.3°C (81.1°F) and lows of 20.4°C (68.7°F).
What is the least humid month?
With an average relative humidity of 77%, July is the least humid month.
What is the driest month?
The only month without rainfall is July.
What is the month with the coldest sea water?
With an average sea temperature of 25°C (77°F), July is the month with the coldest seawater in São Tomé.
When is the lowest UV index?
With an average maximum UV index of 10, July is the month with the lowest UV index.
When does it rain?
Months with rainfall are January through June, August through December.
What is the month with the least sunshine?
With an average of 3.7h of sunshine, October has the least sunshine of the year in São Tomé, São Tomé and Príncipe.
What is the month with the shortest days?
With an average of 12h and 6min of daylight, December has the shortest days of the year.
Is there Daylight Saving Time (DST)?
São Tomé does not utilize Daylight Saving Time (DST). GMT timezone is used over the entire year.
Average temperature
São Tomé, São Tomé and Príncipe
The warmest month (with the highest average high temperature) is March (30.2°C).
The month with the lowest average high temperature is July (27.3°C).
The months with the highest average low temperature are March, April and May (22.6°C).
The coldest month (with the lowest average low temperature) is July (20.4°C).
Average humidity
São Tomé, São Tomé and Príncipe
The months with the highest relative humidity are January, November and December (85%).
The month with the lowest relative humidity is July (77%).
Average rainfall
São Tomé, São Tomé and Príncipe
- Average rainfall in January:
81mm - Average rainfall in February:
84mm - Average rainfall in March:
131mm - Average rainfall in April:
122mm - Average rainfall in May:
113mm - Average rainfall in June:
19mm
The wettest month (with the highest rainfall) is March (131mm).
The driest month (with the least rainfall) is July (0mm).
Average rainfall days
São Tomé, São Tomé and Príncipe
- Average rainfall days in January:
8 days - Average rainfall days in February:
8 days - Average rainfall days in March:
12 days - Average rainfall days in April:
11 days - Average rainfall days in May:
10 days - Average rainfall days in June:
3 days
- Average rainfall days in July:
2 days - Average rainfall days in August:
3 days - Average rainfall days in September:
6 days - Average rainfall days in October:
12 days - Average rainfall days in November:
11 days - Average rainfall days in December:
8 days
The months with the highest number of rainy days are March and October (12 days).
The month with the least rainy days is July (2 days).
Average sea temperature
São Tomé, São Tomé and Príncipe
The best months for swimming (with the highest average sea temperature) are February, March and April (29°C).
The coldest month (with the lowest average sea temperature) is July (25°C).
Average daylight / Average sunshine
São Tomé, São Tomé and Príncipe
- Average daylight in January:
12h and 1min - Average daylight in February:
12h and 1min - Average daylight in March:
12h and 1min - Average daylight in April:
12h and 1min - Average daylight in May:
12h and 1min - Average daylight in June:
12h and 1min
- Average daylight in July:
12h and 1min - Average daylight in August:
12h and 1min - Average daylight in September:
12h and 1min - Average daylight in October:
12h and 1min - Average daylight in November:
12h and 1min - Average daylight in December:
12h and 1min
The month with the longest days is June (Average daylight: 12h and 6min).
The month with the shortest days is December (Average daylight: 12h and 6min).
- Average sunshine in January:
4h and 4min - Average sunshine in February:
4h and 5min - Average sunshine in March:
4h and 3min - Average sunshine in April:
4h and 1min - Average sunshine in May:
4h and 4min - Average sunshine in June:
5h and 3min
- Average sunshine in July:
5h and 1min - Average sunshine in August:
4h and 5min - Average sunshine in September:
4h and 0min - Average sunshine in October:
3h and 4min - Average sunshine in November:
4h and 3min - Average sunshine in December:
4h and 4min
The month with the most sunshine is June (Average sunshine: 5h and 30min).
The month with the least sunshine is October (Average sunshine: 3h and 42min).
Average UV index
São Tomé, São Tomé and Príncipe
The months with the highest UV index are January, February, March, April, May, August, September, October, November and December (UV index 12).
The month with the lowest UV index is July (UV index 10).
