June to November. This is also the rainy season in St. Lucia. However we are sufficiently low in the Caribbean archipelago that we are rarely impacted by hurricanes. However in recent years we have had some more intense rains than before, but nothing that would ruin your entire holiday. On the flip side December through May is our dry season and from December through mid-February or so the hillsides are lush an green with beautiful blue skies and little to no rain.