There are four distinct seasons in Hong Kong. Hong Kong can be a little chilly in the winter (10°C) and hot and humid in the summer (33°C). The best times of year to visit are thus, spring (March-May), when the average temperature is around 25°C and autumn (September-December). Christmas in Hong Kong can be a delight with a fair chance of mild sunny weather that will appeal to those coming from colder northern climates. Hotels experience peak occupancy in the months of April and October. Typhoons usually occur between June and September and can bring a halt to local business activities for a day or less. The weather in winter is usually caused by the winter monsoon which brings dry cold winds from the north. In winter the air can be cold but the sun can still burn. Expect winter temperatures to rise to 22°C on sunny days and fall to under 10°C at night, especially when in mountainous areas. Chinese New Year is notorious for cold wet weather and, since many businesses close, non-Chinese tourists will not see Hong Kong at its best. Should you find yourself in Hong Kong at Chinese New Year, you can make the best of the weather by going hiking if it is dry.
Although most buildings in Hong Kong have air conditioning to cope with the summer weather, winter heating is something of a novelty. During the coldest days, the lack of heating and thermal insulation can be a challenge, especially at bath time. Curiously, buses and many restaurants will continue to use air conditioning to freshen the air, even on the coldest days.