You might spend a lot of your vacation inside, but if you want to see more of the area, looking at local weather trends is a good idea. The hottest months are usually May and April with an average temp of 82°F, while the coldest months are January and February with an average of 79°F. The rainiest months in Vigan are August, July, June, and September, with each month seeing an average of 23 inches of rainfall.