If you're hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Nevis: The hottest months are usually July and August, with an average temperature of 18°C, while the coldest months are January and February, with an average of -9°C. The snowiest months in Nevis are April, March, January and October, with each month seeing an average of 21 cm of snowfall.