Halong Bay belongs to the northern weather patterns of Vietnam so it is generally cooler than the southern half of the country. It experiences two main distinct seasons. The spring, from February to April is glorious, with clear skies and cool evening breezes. Flowers begin to bloom and trees and bushes sprout new foliage. In the summer from May to August, the whole region is quite hot, perfect for swimming and sun-bathing. Temperatures may rise to 37属C (98.6 属F) in June and July.. In autumn, September to November the weather is cooler with the chance of storms although they are short-lived. The air is clear, perfect for photography and all our scheduled activities. Although the winter months from late November to January are quite cold, it is the peak season for the bay. Early morning fog cloaks the islands of Halong in a mysterious beauty. The average winter temperature is 17.2属C (62.9属F) and deep inside the bay it is often colder, sometimes below 10属C (50属F) for long periods. Bundle up and sit on the deck to watch the karst islands emerge from the mist or relax in your heated rooms.