September weather forecast
Portsmouth, Dominica

September nudges ahead to claim the wettest month title in Portsmouth, accumulating an average rainfall of 269mm (10.59"). Daylight hours slightly decrease, reflecting autumn's approach. Despite the climatic shift, the sea temperature maintains a warm average, catering to water activities. Concurrently, the UV index takes a gradual dip. Transitioning towards October, rainfall rates remain relatively constant with minor fluctuations.

Temperature

In Portsmouth, June through September are characterised by the peak of temperatures, recording an average high of 31°C (87.8°F).

Rainfall

In September, in Portsmouth, the rain falls for 22 days. Throughout September, 269mm (10.59") of precipitation is accumulated. Throughout the year, there are 214 rainfall days, and 2252mm (88.66") of precipitation is accumulated.

Sea temperature

September is the month with the warmest seawater in Portsmouth, Dominica, with an average sea temperature of 29.4°C (84.9°F).
Note: Swimming, diving, and other activities in water temperatures between 25°C (77°F) and 29°C (84.2°F) are thought to be quite enjoyable and satisfying for extended periods, with no discomfort.

Daylight

In September, the average length of the day in Portsmouth, Dominica, is 12h and 13min.
On the first day of September in Portsmouth, sunrise is at 05:53 and sunset at 18:18. On the last day of the month, sunrise is at 05:55 and sunset at 17:55 AST.

Sunshine

The average sunshine in September in Portsmouth, Dominica, is 7h.

UV index

March through September, with an average maximum UV index of 12, are months with the highest UV index. A UV Index reading of 11, and higher, represents an extreme threat to health from exposure to the Sun's UV radiation for average individuals.
Note: The maximum daily UV index, 12 in September, converts into the following recommendations:
Adopt every vital precaution, unprotected skin and eyes may burn rapidly. Stay in the shade and limit sun exposure from 10 a.m. to 4 p.m., when UV radiation is most potent. Keep in mind that shade structures like parasols or canopies do not offer full protection. To cut down UV radiation exposure by about half, sport a wide-brim hat. A sunscreen with at least SPF 30 should be used liberally and reapplied frequently on cloudy days, especially after swimming or an outdoor workout. Caution! The mirror effect of sand and water ups the UV radiation strength.