World Resorts Saint Lucia Castries Weather

Castries weather in September

Weather in Castries: September

Average day temperature: 86.8°F
Average night temperature: 81.8°F
Sea water temperature: 84.8°F
Number of sunny days: 4 days
Day length: 12.0 - 12.4 hours
Number of rainy days: 5 days
Precipitation totals: 3.5 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 87°F. At the same time the lowest night temperature was 80°F. Daily and nightly averages during September were 85.9°F and 81.5°F.

Sea water temperature in Castries in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 85.5°F. The highest and lowest sea temperatures during the month were 85.8°F and 84.9°F.

Sunny, partly cloudy and cloudy days

Mostly all days in September are partly cloudy but sunny or cloudy days are also possible.

Precipitation total in September, in.

Precipitation total value in Castries in September is 4.2 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 10.8 mph It makes September lest windy month of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 5.7.

Best time for vacation in Castries

Sunniest months:
December 4 days
March 4 days
September 4 days
Warmest months:
September 86.8 °F
October 86.0 °F
August 85.8 °F
Warmest sea temp:
September 84.8 °F
October 84.6 °F
August 84.0 °F
Coldest months:
January 81.9 °F
February 81.9 °F
March 82.2 °F
Rainiest months:
August 7 days
October 5 days
September 5 days
Windiest months:
June 15.7 mph
February 15.4 mph
January 15.1 mph

Castries on a weather map

Castries
+79°F
W 17 mph
Feels like: +82°F
Precip.: 100%
Places in Saint Lucia:
Name
°F
+79°F
+79°F
24 Hours Forecast
Castries
Local time: 00:02
December 05, friday
0300
77°F
W
16 mph
0600
79°F
W
15 mph
0900
81°F
W
17 mph
1200
81°F
W
17 mph
1500
79°F
W
19 mph
1800
79°F
W
17 mph
2100
79°F
W
19 mph
December 06, saturday
0000
79°F
W
19 mph
Units of measurement: °C / °F