September weather forecast
Nuku'alofa, Tonga

September in Nuku'alofa witnesses the commencement of a mild climb in temperatures. The effect of this slow ascend is visible with a high of 25.3°C (77.5°F). It records a minor surge in rainfall compared to August, indicating the progressive shift towards the wetter seasons. The daylight duration extends noticeably, shedding more light on the island's beauty. The sea temperature mimics the air's warming trend, appealing to those wanting to paddle amid the turquoise waves.

Temperature

September registers an average high-temperature of a still warm 25.3°C (77.5°F), slightly varied from August's 24.8°C (76.6°F). During September, Nuku'alofa experiences a consistent low-temperature average of 18.6°C (65.5°F).

Humidity

In September, the average relative humidity is 74%.

Rainfall

In Nuku'alofa, during September, the rain falls for 13 days and regularly aggregates up to 122mm (4.8") of precipitation. Throughout the year, there are 180 rainfall days, and 1721mm (67.76") of precipitation is accumulated.

Sea temperature

The months with the coldest seawater are August and September, with an average sea temperature of 23.8°C (74.8°F).
Note: If someone is sensitive to cold, the enjoyment of swimming in 23.8°C (74.8°F) water hinges on factors like sunshine, wind, and the current air temperature. (For context: Olympic swimming competitions are held in water temperatures of 25°C (77°F) to 28°C (82.4°F).)

Daylight

The average length of the day in September is 11h and 59min.
On the first day of the month, sunrise is at 06:49 and sunset at 18:32. On the last day of September, sunrise is at 06:21 and sunset at 18:39 +13.

Sunshine

In Nuku'alofa, the average sunshine in September is 4h.

UV index

The average daily maximum UV index in September is 10. A UV Index of 8 to 10 symbolizes a very high threat to health from exposure to the Sun's UV rays for ordinary individuals.
Note: In September, a regular UV index of 10 translates into these guidelines:
Always stay safe. Unprotected skin and eyes can get damaged rapidly. Stay in the shade and avoid direct Sun exposure from 10 a.m. to 4 p.m., a period when UV radiation is particularly strong, noting that parasols or canopies may not offer total sun protection. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days. Combat sunburn and harmful sun radiation by consistently applying sunscreen with at least 30 SPF. Notice! The reflection of water and sand increases the UV radiation significantly.