Best time to visit
The best time to visit the Philippines is during the dry season, when the humidity is low and temperatures are tolerable. For most parts of the country this is from December to May. Temperatures are year round tropical, with January and February being the coolest months. From March it gets steadily hotter and hotter. April and May are the hottest months of the year with lots of sunshine. The rain starts to arrive around the end of April and slowly gets more intense towards August.
Rain might be inconvenient, but typhoons will certainly disrupt your travel scheme. The typhoon season starts around June and lasts until September. Be aware that during this period some touristic sights and businesses close down. On the other side - prices tend to be significantly lower and on average only 5 typhoons a year hit the country. Fortunately not all parts of The Philippines are in the danger zone, Mindanao, Palawan and the Southern Visayas are rarely affected by typhoons.
Another aspect to factor in your travel plans are the Philippines national- and school holidays. The super peak season is during Christmas and Holy week when prices skyrocket and accommodation is filling up quickly. April until June is school holiday and during this time Filipinos tend to head out to the beaches and highlands.