Hong Kong's climate ranges from cool and relatively dry to hot and very humid, with the occasional typhoon rounding out the year. Even in the dead of winter, frost is a rare occurrence in Hong Kong. This all sounds pleasant and warm, which it often is, but be sure to pack a sweater to stave off the occasional chill. The region's extreme humidity adds an element of dampness that can make you feel cooler than the temperature alone would indicate. Hong Kong's short season of spring is generally considered the next best time to visit.
Temperatures rise quickly, as does the level of humidity.
Weather wise, summer is the least appealing time to visit Hong Kong, as it's the hottest, rainiest, and most humid part of the year. Rains fall, winds can pick up, and typhoons are not an uncommon occurrence. Ultimately, when you consider both crowds and weather, the shoulder seasons of late spring and early autumn may be your best bets. Still, the weather can be risky, because of the always-present possibility of early or late rains. In the end, the importance of the weather is personal.