Portsmouth, in Saint John Parish, DM, is home to roughly 3,600 people in the America/Dominica time zone at 15.6°N latitude.
In 2025, Portsmouth recorded an average annual temperature of 79°F. The hottest temperatures reached 90°F in October; the coolest were 69°F in April. Total precipitation for the year was 54 inches, with the wettest month being February.
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