Kota Kinabalu experiences tropical rainforest climate with constant temperature throughout the year. However, this place does experience heavy rainfall in certain seasons, but the humidity is never far behind. There is rain throughout the year in the city and days range from warm to hot and humid. There are basically two types of seasons:
Dry season: May to September & November to March are the dry season in Kota Kinabalu with June being the driest month. If you are travelling in this season, make sure you carry sunscreen, sunglasses and a hat to protect yourself from the scorching heat. Hence, if you are coming Kota Kinabalu in this season be prepared to face the rush of this peak season.
Wet season: This season usually comes between April to May and November. During this season, the rainfall tends to switch between early morning hours and late afternoon period. Though the climate is more humid as compare to dry season, there is less chance of facing the tourist crowd on the road.
So, Kota Kinabalu can be visited at any time of the year. However, to be specific dry season, especially June to August is considered as the best time to visit Kota Kinabalu.