Climate and monthly weather forecast
British Indian Ocean Territory

The British Indian Ocean Territory, known as the Chagos Archipelago, is located in the central Indian Ocean, to the south of the Maldives. This territory consists of 55 individual islands spanning a vast marine expanse. Given its geographical location near the equator, the British Indian Ocean Territory is characterized by a tropical climate, with warm and humid conditions present year-round. The average temperature generally ranges between 24°C (75.2°F) and 32°C (89.6°F), while relative humidity tends to be high, commonly exceeding 80%. The area receives abundant rainfall, with annual precipitation levels averaging 2600mm (102.36"). There are no discernible seasons, with weather remaining consistently tropical throughout the year.

The best time to visit the British Indian Ocean Territory largely depends on what activities visitors intend to engage in. However, the period from May to October is typically deemed the most favourable. This is the dry season, with slightly less rainfall and humidity, which makes for more comfortable conditions for outdoor activities, such as exploring the islands or snorkeling in the clear ocean waters. In these months, the average temperature hovers around 28°C (82.4°F), making it pleasant and not excessively hot.

Conversely, the period from November to April is considered less ideal for visiting the British Indian Ocean Territory. These months mark the monsoon season, with frequent and heavy rainfall. The increased humidity during this time can also make the temperature feel hotter than it actually is. Cyclones can occur, although they are relatively infrequent, with the territory lying somewhat beyond the main cyclone belt. These conditions may disrupt travel and outdoor activities.

As a tropical territory, the British Indian Ocean Territory does not experience the traditional four seasons of temperate regions. Instead, the climate is relatively stable throughout the year. However, for the purpose of comparison, in the period that would be spring in temperate climates (March to May), the weather in the British Indian Ocean Territory is moving towards the drier period of the year. Temperatures average from 26°C (78.8°F) to 30°C (86°F), and the rainfall begins to decrease, though still remains quite high.

In the months corresponding to a temperate summer (June to August), the British Indian Ocean Territory experiences what can be considered its dry season. Rainfall drops off significantly during these months, and temperatures maintain an average between 25°C (77°F) to 28°C (82.4°F). These conditions make for relatively pleasant weather with warm days and cooler nights, ideal for exploring the natural beauty of the archipelago.

In the months analogous to autumn in temperate regions (September to November), the British Indian Ocean Territory begins to transition back to its wetter season. Average temperatures remain steady, between 26°C (78.8°F) and 30°C (86°F), and rainfall begins to increase, though not as heavily as during the peak monsoon months. It is still a good period to visit, with conditions being relatively mild and less humid than in the monsoon season.

Winter, in the conventional sense, does not occur in the British Indian Ocean Territory. In the period that would be winter in temperate regions (December to February), the region experiences its wettest months. This is the peak of the monsoon season, with heavy rainfall and increased humidity. The temperature averages from 26°C (78.8°F) to 30°C (86°F), with the high humidity making it feel warmer. Travel during this period can be challenging due to the heightened risk of disruptions caused by inclement weather.

January lies within the wet season in the British Indian Ocean Territory. The islands experience heavy precipitation during this month, often with daily rainfall, as this period marks the peak of the monsoon season. Average rainfall in January can reach up to 260mm (10.24"), making it one of the wettest months of the year. The temperature in January stays relatively high, with average temperatures ranging from 26°C (78.8°F) to 29°C (84.2°F). Weather in January »

In the British Indian Ocean Territory, February continues the monsoon season that begins in November. This period is characterized by high levels of rainfall, humidity, and warm temperatures. February experiences an average precipitation of about 200mm (7.87"), a slight decrease from January, but it remains one of the wetter months of the year. Temperatures in February continue to hover between 26°C (78.8°F) and 30°C (86°F), akin to January. Weather in February »

In the British Indian Ocean Territory, the month of March signifies the transition phase from the wet season to the beginning of the drier period. March experiences a decrease in rainfall compared to February, with an average precipitation of approximately 170mm (6.69"), a noticeable reduction that signals the end of the monsoon season. Temperatures during March remain warm, ranging from 26°C (78.8°F) to 30°C (86°F), maintaining the typical tropical warmth of the islands. Weather in March »

The month of April in the British Indian Ocean Territory further advances the shift from the wet to the dry season. Precipitation levels continue to decrease, with an average rainfall of about 150mm (5.91"), a slight reduction from March. Weather in April »

May marks the onset of the dry season in the British Indian Ocean Territory. The shift from the wet monsoon season is signaled by a further decrease in precipitation levels. Rainfall in May averages around 130mm (5.12"), continuing the downward trend from April and significantly lower than the peak monsoon months. Average temperatures during May remain fairly consistent with the preceding months, ranging from 26°C (78.8°F) to 28°C (82.4°F). Weather in May »

June in the British Indian Ocean Territory is characterized by the continuation of the dry season, with noticeably lower precipitation levels compared to the wet season. Average rainfall in June is approximately 80mm (3.15"), marking a significant reduction from May, and making it one of the driest months of the year. Temperatures in June remain relatively stable, with averages ranging from 25°C (77°F) to 27°C (80.6°F). Weather in June »

July in the British Indian Ocean Territory continues to observe the dry season's conditions. The average rainfall for July is approximately 70mm (2.76"), indicating a slight decrease from June and maintaining its status as one of the driest months of the year. Temperatures in July maintain a steady range similar to June, with averages from 25°C (77°F) to 27°C (80.6°F). Weather in July »

In August, the British Indian Ocean Territory maintains the dry season's conditions, characterized by low rainfall and consistent temperatures. The average rainfall is approximately 80mm (3.15"), a slight increase from July, but still well below the levels observed in the wet season. Temperatures in August continue the consistent pattern observed in previous months, with averages ranging from 25°C (77°F) to 27°C (80.6°F). Weather in August »

September in the British Indian Ocean Territory marks the onset of the transition period from the dry season back to the wet season. Rainfall begins to increase during this month, with an average precipitation of 100mm (3.94"), a noticeable rise compared to August, yet significantly lower than peak monsoon months. Average temperatures in September maintain a range similar to preceding months, varying from 25°C (77°F) to 27°C (80.6°F). Weather in September »

October in the British Indian Ocean Territory represents a further progression into the wet season, characterized by a significant increase in rainfall. Average precipitation during this month rises to approximately 150mm (5.91"), a noticeable leap from September, indicating the return of the monsoon season. Temperatures in October maintain consistency with the preceding months, averaging between 25°C (77°F) and 27°C (80.6°F). Weather in October »

November in the British Indian Ocean Territory marks the further deepening of the wet season. The monsoon's influence becomes more pronounced, with average rainfall increasing to 200mm (7.87"), a substantial rise from October. Weather in November »

December in the British Indian Ocean Territory continues the conditions of the wet season, characterized by high levels of rainfall. The average precipitation during this month is approximately 220mm (8.66"), an increase from November, making December one of the wettest months of the year. Temperatures in December maintain a range similar to previous months, with averages from 26°C (78.8°F) to 28°C (82.4°F). Weather in December »