The weather in Saint Lucia is very agreeable most of the time, being warm with sea breezes and around 8 to 11 hours full sun every day.
Being near the equator means the day lengths vary very little over the course of the year.
This is a lovely sunny morning on jalousie beach right between the pitons.
The average Temperarture is between 25°C in January to 28°C in October / November with the min max between 22°C and 35°C. Whilst it can be colder or warmer it rarely so.
The humidity is constant between 70 and 80%
The sea temperature is always warm, between 22°C and 25°C depending on the time of day/year and location. It is generally clear unless hurricane or severe bad weather have stirred the sea up.
Being lush and tropical it rains quite often and you will likely get at least 4 showers a week but probably more like 8 or 10. the rain is mostly confined showers, is generally warm and transient and not difficult to deal with.