Climate and monthly weather forecast
Tonga

Tonga is an archipelago situated in the South Pacific Ocean. Its geography is predominantly comprised of 169 islands, with 36 of these being inhabited. The terrain ranges from low-lying coral atolls to larger, volcanic islands with fertile soil. The nation's position, between 15°and 23.5°south of the equator, renders it a prime target for tropical conditions. Based on the Köppen climate classification, Tonga experiences a Tropical Rainforest Climate, denoted as "Af". High temperatures are the norm, with the average monthly figures persistently around or above 18°C (64.4°F). A distinctive feature of this climate is the substantial rainfall occurring year-round. There is no discernible dry season, with all months recording significant precipitation levels, ensuring a lush and vibrant tropical environment.

The preferred time to visit Tonga tends to be between May and October. During these months, the country experiences its cooler season, with temperatures averaging between 21°C (69.8°F) to 27°C (80.6°F). This period is also less rainy than other times of the year, which can make outdoor activities and travel more enjoyable. Visitors can relish the verdant landscapes, pristine beaches, and remarkable marine biodiversity with more comfort and less disruption from heavy rains or high heat.

The months between November and April form the cyclone season, which is considered the least suitable time to visit Tonga. This period is characterized by higher temperatures, ranging from 24°C (75.2°F) to 31°C (87.8°F), and increased humidity. Moreover, the archipelago becomes more susceptible to tropical cyclones, leading to heavy rainfall and potential disruptions to travel plans. While it is still possible to visit during this time, visitors must be aware of the potential weather conditions and stay informed about weather updates.

In the context of a tropical climate, the term "spring" can be misleading. Tonga experiences relatively consistent temperatures year-round, and does not have a spring season in the traditional sense. However, for the sake of comparison, during the months that would typically constitute spring in temperate zones (September to November), Tonga sees average temperatures from 23°C (73.4°F) to 29°C (84.2°F). Precipitation is prevalent as the nation transitions into the cyclone season, particularly in November. Humidity levels rise, and the possibility of cyclones begins to increase.

Again, with a tropical climate, there is no real summer season as per temperate climates. Nevertheless, during the months of December to February, temperatures range from 24°C (75.2°F) to 31°C (87.8°F). These months are some of the wettest in the year due to the cyclone season. This period is characterized by heavy rains and high humidity. Although this season is less optimal for tourism, the islands still possess their intrinsic charm, with the abundant rainfall serving to intensify the lushness of the tropical flora.

The period from March to May, which coincides with autumn in temperate zones, features temperatures ranging from 22°C (71.6°F) to 29°C (84.2°F) in Tonga. The rainfall gradually decreases as the cyclone season draws to a close. From mid-April onwards, the weather begins to stabilize, and humidity decreases, providing more comfortable conditions. The end of this period, particularly May, can be a good time to visit as the weather is relatively cool and the risk of cyclones is significantly reduced.

In a tropical setting like Tonga, "winter" refers to the cooler and drier part of the year rather than a season of freezing temperatures. During the months of June to August, Tonga experiences average temperatures between 21°C (69.8°F) and 27°C (80.6°F). This period witnesses the lowest rainfall figures for the year, making it the most comfortable and most favored time for tourists to visit. The weather during these months is ideal for exploring Tonga's natural beauty, engaging in water sports, or simply relaxing on the country's many stunning beaches.

January is situated in the midst of Tonga's cyclone season, which is characterized by higher temperatures, increased humidity, and a higher likelihood of extreme weather events. Across the archipelago, temperatures during January range from 24°C (75.2°F) to 31°C (87.8°F). Weather in January »

February is in the peak of the cyclone season in Tonga, characterized by high temperatures and an increased likelihood of extreme weather events. Average temperatures across the islands during this month are generally consistent, ranging from 24°C (75.2°F) to 31°C (87.8°F), comparable to January. Precipitation remains high in February, with average monthly totals often exceeding 120mm (4.72"). Weather in February »

March signifies the winding down of the cyclone season in Tonga. Temperatures during this month range from 23°C (73.4°F) to 30°C (86°F), showing a slight decrease compared to the warmer months of January and February. Rainfall in March begins to decrease as well, although it remains significant with an average total often exceeding 110mm (4.33"). Weather in March »

April in Tonga marks a further shift away from the cyclone season, as the weather becomes more stable. Temperatures continue to show a slight decrease from the warmer months, ranging from 22°C (71.6°F) to 29°C (84.2°F). Rainfall in April continues the downward trend established in March, although the average precipitation remains substantial at 100mm (3.94"). Weather in April »

May signifies the onset of the cooler season in Tonga. This month sees a further decrease in temperature, with average readings ranging from 21°C (69.8°F) to 27°C (80.6°F). As such, May is often considered one of the more comfortable months to visit Tonga in terms of temperature. Rainfall in May continues its downward trend from the previous months, averaging 90mm (3.54"). Weather in May »

June in Tonga marks the beginning of the true dry season, with the cooler, less humid conditions making it one of the more comfortable periods to visit the country. Temperatures during June typically range from 19°C (66.2°F) to 26°C (78.8°F), the cooler end of the spectrum for the archipelago. Rainfall in June is significantly reduced compared to the wetter months, with an average precipitation of 80mm (3.15"). Weather in June »

July represents the mid-point of the dry season in Tonga, offering some of the most pleasant and predictable weather conditions of the year. Temperatures during this month range from 18°C (64.4°F) to 25°C (77°F), making July one of the coolest months in the archipelago. The average rainfall in July continues to decrease, dropping to 70mm (2.76"). Weather in July »

August continues the trend of the dry season in Tonga, with weather conditions generally favourable for visitors. Average temperatures remain quite stable compared to July, ranging between 18°C (64.4°F) and 25°C (77°F). This makes August another of the coolest months in Tonga, providing a reprieve from the high heat of the wet season. Rainfall in August continues to be relatively low, with an average precipitation of approximately 70mm (2.76"). Weather in August »

September in Tonga sees the beginning of the transition from the cooler, drier conditions of the mid-year to the warmer, wetter conditions of the late-year. Temperatures during September typically range from 19°C (66.2°F) to 26°C (78.8°F), marking a slight increase from the cooler months of July and August. Average rainfall in September begins to increase, marking the end of the dry season. Weather in September »

October in Tonga is a transitional month, with weather conditions starting to shift towards those typical of the wet season. Average temperatures during October range from 20°C (68°F) to 27°C (80.6°F), signaling a gradual increase from the preceding months. Rainfall in October continues its upward trend from September, averaging 90mm (3.54"). Weather in October »

November in Tonga marks the official start of the cyclone season, with weather conditions becoming warmer and wetter. Average temperatures during November range from 21°C (69.8°F) to 28°C (82.4°F), indicating a continued increase from the cooler dry season. Rainfall in November sees a significant increase, with averages rising to 110mm (4.33"). Weather in November »

December in Tonga is characterized by typical wet season conditions, with higher temperatures and increased rainfall. Average temperatures during December typically range from 22°C (71.6°F) to 29°C (84.2°F), marking some of the highest readings of the year. Rainfall in December continues to rise, with averages around 140mm (5.51"). Weather in December »