Although weather is just one factor, it can really affect your travel plans, especially if you are planning a longer stay in Gapan City. The hottest months are usually May and April, with an average temperature of 28°C, while the coldest months are January and February, with an average of 25°C. The rainiest months in Gapan City are July, September, August and June, with each month seeing an average of 348 mm of rainfall.