General Overview

Dominica is a Lesser Antilles island that is often confused with the Dominican Republic, which is a much more populated country (nearly 10 million residents vs around 75,000 in Dominica) spanning much more than the 748.5 square kilometres (289 square miles) of Dominica’s overall size.

Dominica belongs to the Commonwealth and as all its other counterparts, it has a tropical climate featuring humid and hot months throughout the year and a relatively dry and cool season between the months of January and April. As for its rainy, humid, and hot season, it starts in mid-June and ends around mid-November.

During the dry season, the island is cooled by the steady, northeast trade winds that typically blow in tropical climates, with moderate intensity. The trade winds change at some pointl, though, and become more irregular and often have small breaks, which increases the sensation of sultriness. In between these two periods, meaning the months between mid-November through early-January, the island experiences a transitional period, when the northeast wind begins to blow, the weather gets better, and the temperatures drop by a little. From mid-April to mid-June, the frequency of rainfalls slowly increases and the temperatures gradually rise.

Overall, Dominica experiences very little variations in its warmest and coldest temperatures, as shown in the table below.

Average temperatures

Rainfall in Dominica

The island receives lots of rain throughout the year. Typically, the wet season in Dominica runs from June to December and its dry season from January to May, with December and May being regarded as the transition months, according to the Dominica Meteorological Service.

Also, historical data from the same service showcases that April is the driest month, with an average of 60 millimetres or mm (or 2.4 inches) of rain. What is noteworthy at this point is the fact that this amount of rain is the highest one can get from some Caribbean islands amidst the hurricane season.

That being said, there is significant variation in the amount of rainfall received on the west coast compared to the east coast and the interior of Dominica. For instance, west coast-sitting Roseau receives nearly 2,000 mm (78 inches) of rainfall annually, primarily between July and November. At the same time, its least rainy season is from February through April, when its monthly average precipitation falls to around 75mm (3 inches) as shown in the table below.

Average precipitation in Roseau (West Coast)

The eastern coast is a different story, though, as it gets around 500mm (19.68 inches) more rain annually than the west coast, mainly due to its exposure to the trade winds. Furthermore, the temperatures are a bit lower by a couple of degrees during the day, while the humidity is higher.

As for the interior of Dominica, the rains are even more abundant and frequent as the land is almost entirely covered by mountains, hills, and rainforests. In fact, the conditions are so much different than the rest of the island that the climate is defined as equatorial!

Finally, the northern part of Dominica receives an impressive 9,000mm (354 inches) of rain annually, especially higher altitudes like the ones of the Monte Diablotins volcano (nearly 1,500 metres or 4,800 feet high).

Sunshine Hours

The good thing about Dominica is that its rains are generally not long-lasting, even though they occur as thunderstorms or downpours throughout the year. This means that they don’t have a detrimental effect on the sunshine hours travellers and locals get. Of course, there might be times when a wave of bad weather is more intense.

That being said, the amount of sunshine the island gets annually is more than satisfactory and enough for pleasant vacations as the average hours of daily sunshine ranges from 6 in December through 8 in April, May, and August, and an annual total of around 2630 hours (7.2 hours of sunshine on average daily).

Sunshine hours

Sea Temperature

The temperature of the water in Dominica is enjoyable enough to swim or snorkel almost year-round, ranging from 20oC (84oF) in September and October to 26.5oC (79.5oF) in February and March. Of course, seawater is always warmer in the late afternoon and cooler in the morning. On average, the sea temperature is around 27.8oC (82.1oF), which can even be described as ideal for water sports.

Sea temperature

Hurricane Season

Hurricanes, which are, in reality, cyclones or tropical storms of high intensity, are the greatest danger for Dominica and the Caribbean, in general. Although not frequent, they can pass over Dominica between the months of June and November. However, statistics show that Dominica has a higher chance of being struck by a hurricane from August through October. Nevertheless, if one looks at the data from the Dominica Meteorological Service will clearly realise that the island is rarely hit by a destructive hurricane. The last one reported of that magnitude was Hurricane Maria in 2017 which struck the island almost forty years after the previous damaging hurricane (Hurricane David) occurred in 1979. In any case, even if a hurricane does not hit Dominica, it may as well bring wind damage and floods from heavy rain if it passes nearby.