When you travel with your pet, keeping track of the weather can help you make the trip more safe and fun for everyone. The hottest months are usually April and May, with an average temperature of 18°C, while the coldest months are January and December, with an average of 14°C. The rainiest months in San Sebastián Xolalpa are August, July, September and June, with each month seeing an average of 176 mm of rainfall.