Weather locations in Dominica

Dominica is the northernmost of the Windward Islands, a volcanic island of steep and forested mountains rising to 1,497 metres at Morne Trois Pitons. It sits close to the main track of Caribbean storms, and everything about the weather is shaped by the island's enormous relief: the windward Atlantic side is drenched, and the leeward, Caribbean side is markedly drier. It is one of the wettest islands in the Caribbean.

Main climate types

Dominica is classed as a tropical rainforest climate, meaning rain in every month. Because the trade winds blow across the island throughout the year, the eastern and south-eastern slopes of the Morne Trois Pitons and Morne aux Diables massifs are among the wettest places in the Caribbean, with high-slope totals running to several thousand millimetres a year. The leeward coast around Roseau is much drier, and a semi-arid pocket lies on the north-west coast near Portsmouth.

Temperatures

There is essentially no cold season. At Roseau, monthly means run from about 24 °C in January to about 26 °C in July and August, with maximums rarely above around 31 °C and night-time lows near 21 °C. In the mountains the temperature falls by several degrees per kilometre of ascent, and the summit ridges are cool and often cloud-covered even in midsummer. Sea temperatures stay between about 24 °C and 28 °C.

Rainfall

Roseau records roughly 1,800 to 2,000 mm a year, with no month averaging less than about 100 mm. The distribution matters less than the total: showers can arrive at any hour, and the mountains are often under cloud while the coast is in sunshine. Heavy rain is common from about June to November, coinciding with the Atlantic hurricane season, and landslides and flash floods are the main hazard.

When to go

For most visitors the most comfortable months are February to April, when the trade winds are firm and the air slightly drier. Late autumn carries the highest hurricane risk, and December to January can be cool and wet at higher elevations. Walking to the Boiling Lake or the Morne Trois Pitons viewpoint is best done in January, when the ridges clear, and should never be attempted without proper boots and a local guide.