Taking into account the local weather in San Jerónimo is an important factor for planning your visit, especially if you plan to spend your trip poolside. The hottest months are usually August and July with an average temp of 66°F, while the coldest months are December and January with an average of 64°F. The rainiest months in San Jerónimo are May, April, October, and November, with each month seeing an average of 16 inches of rainfall.