Halong Bay has a tropical monsoon climate with two main seasons: the hot and rainy season from May to October and the cool and dry season from November to April. During the hot season, temperatures can reach up to 35°C with high humidity and frequent rain showers, while during the cool season temperatures average around 20°C with less rainfall. Overall, the best time to visit Halong Bay is from October to April when the weather is pleasant and the visibility is better for viewing the scenic landscape.
Halong Bay Weather in Fall & Spring (September to November and March to May)
+ Lowest temperature: 13ºC
+ Highest temperature: 32ºC
+ Humidity: 79%-85%
Deciding on the best time to visit will depend on your personal preferences. As many people prefer the cool, dry weather of Spring and Fall, the peak visiting times tend to be from March to April and September to October. During these months, you can expect more sunny days, a cooler breeze and calmer weather. A minor shower is to be expected occasionally, but they rarely last long enough to disrupt visitors’ plans.
Halong Bay Weather in Summer (May-September)
+ Lowest temperature: 21ºC
+ Highest temperature: 38ºC
+ Humidity: 81.5%
Summer lasts from around May to September, and in this time, the air is hot and humid. This warmer weather helps create beautiful sunsets, viewable at times when there is no rain or fog. While the promise of summer heat can be tempting, the months of July to September are also the wettest, so visitors should check weather forecasts for signs of severe weather. Temperature high for these months is 38°C.
Winter (November to March)
+ Lowest temperature: 10ºC
+ Highest temperature: 19ºC
+ Humidity: 79.2%
Winter lasts from around November to March. These months are the coldest with temperatures dropping down to 10°C – 20°C on average with a low of 16°C. This is also the dry season, not a lot of rainfall is to be expected.
Halong Bay in Dember
+ Monsoon Influence: Halong Bay is influenced by the monsoon climate; which brings heavy rain and high humidity in the summer months.
+ Cooler Winters: Winter temperatures in Halong Bay can drop to as low as 10°C, making it a refreshing change from the hot and humid summers.
+ Foggy Conditions: Halong Bay can be prone to foggy conditions, particularly in the winter months; adding to the ethereal beauty of the bay.
+ Rainy Season: The rainy season in Halong Bay can bring heavy downpours, but these also help to maintain the lush vegetation and keep the bay thriving.
+ Tropical Storms: Halong Bay is vulnerable to tropical storms, which can bring strong winds and heavy rain; It’s important to check the weather forecast before visiting the bay during the storm season.
+ Halong is one of the most humid cities in Vietnam with the average annual humidity at 84%, which fluctuate from a minimum of 68% to a maximum of 90% in a year.