Really, every picture you've seen of St. Lucia shows it covered in clouds? Interesting! :-)

No, it is not always cloudy or rainy or overcast - I am currently sitting in my balcony with not a single cloud in the sky, even looking towards the interior towards the north - beautiful sunny (hot) blue skies. That said - it is a rainforest island with mountain ranges - there are often clouds and showers in the interior while the coastlines are crystal clear and hot.

Dec is the beginning of the "drier" period, weather is usually pretty good - hot during the day, a bit cooler at night (read 27-30 day and 26-27 night) occasional passing showers, etc. Perhaps it would help if you read the Top Question dealing with weather on the top right of this page - if you are on your phone, you would have to load the "full site" before you could see the Top Questions.

Enjoy your visit.