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St. Lucia

St. Lucia Weather in September: Rain, Temperatures

St. Lucia weather in September
Average high temperature and rainfall for St. Lucia in September. © 2023 Scott S. Bateman

St. Lucia weather in September is almost the worst of the year. It’s enough to keep away both cruise ships and resort visitors.

Tourism for St. Lucia drops to the lowest point of the year during September, according to the Caribbean Tourism Organization.

But the weather doesn’t keep everyone away. Some brave souls do visit the island’s resorts, especially for last-minute vacations if the weather forecast looks good. Some cruise ships do visit the island. Cruise and resort visitors just shouldn’t expect great weather.

September Rainfall

St. Lucia has average rainfall of eight inches during the month, according to the St. Lucia Meteorological Service.

It is the second highest amount of the year, just barely behind slightly more than eight inches in October.

By comparison, the island averages about two inches during the dry season from February through April.

It rains an average of 20 days during the month, equal to July, August, October and November. It rains only 12 days during April, which is the fewest of the year.

St. Lucia’s risk of rain in September is higher than some eastern Caribbean islands such as Antigua, Barbados and St. Maarten, which average about five to six inches during the month. But it’s not as high as Dominica and Martinique, which average 10 to 12 inches.

St. Lucia Temperatures in September

This video explains Caribbean weather in September and which islands are the best and worst to visit for weather.

Full-Screen Version | YouTube Caribbean Channel
Daytime temperatures in September reach the highest point of the year with an average of more than 87 degrees Fahrenheit or 31 Celsius, according to the St. Lucia Meteorological Service.

Nighttime temperatures stay warm as well with an average of 77 degrees Fahrenheit or 25 Celsius.

Swimmers should find water temperatures comfortable during all times of the day.

Temperatures during the spring dry season are only about two degrees cooler.

Travel planners should think carefully about St. Lucia’s weather in September and whether it makes sense to go there during the month.

Luck plays a big part in weather conditions, but historical averages offer enough information for visitors to expect a higher than normal risk of rain.

Anyone who wants to visit St. Lucia will find that March and April are better choices for a combination of warm temperatures and low risk of rain.

• St. Lucia weather in January - February - March - April - May - June - July - August - September - October - November - December

Scott S. Bateman is a professional journalist who has traveled widely throughout the Caribbean and the Americas. He is the author of four books about cruising in the Caribbean, Alaska and Mexican Riviera.
August 25, 2023

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