Weather in Ha Long

Planning your day or a trip to Ha Long? In this section, you will find the most up-to-date weather information, including detailed forecasts and visual charts, to make your stay as comfortable as possible.

Ha Long, located in Vietnam, has a humid subtropical climate characterized by distinct seasons. The weather here is generally warm and humid throughout most of the year, however, there are notable fluctuations in both temperature and precipitation levels.

Two main seasons can be distinguished. From May to September is the hot and humid rainy season, when average temperatures rise to 27-29°C, and rainfall reaches its maximum, especially in August (about 15 mm) with the highest number of rainy days (up to 28 days in August). From November to April comes the cooler and drier season. During this time, average temperatures drop to 17-24°C, and rainfall is minimal, especially from December to February (1-2 mm), and the number of rainy days decreases significantly.

Thus, when planning a trip to Ha Long, it is worth considering these seasonal features. Summer months bring tropical heat and frequent rains, while winter and spring months offer milder and drier weather, which may be more comfortable for certain types of outdoor activities and excursions.

The temperature pattern in Ha Long demonstrates distinct seasonality. The annual range of average temperatures fluctuates from 16.9°C in January to 29.1°C in June. The hottest month is usually June, when the average daytime temperature reaches 29.1°C, and maximum values can rise to 31.5°C. The coolest month is considered to be January with an average temperature of 16.9°C and minimum nighttime temperatures around 14.4°C.

The summer period, covering months from May to September, is characterized by hot and humid weather. In May, the average temperature is already 27.4°C (fluctuating from 25.1°C to 29.8°C). In June and July, the heat reaches its peak: average temperatures hover around 29.1°C and 28.9°C respectively, with maximum readings regularly exceeding 31°C. Even in September, when the summer heat begins to gradually subside, the average temperature remains high – around 27.5°C (with a range from 24.9°C to 30.1°C). This season is distinguished not only by high temperatures but also by significant humidity, which intensifies the sensation of heat.

The winter months, from November to February, bring cooler and more comfortable weather to Ha Long. In November, the average temperature is a pleasant 22.4°C (from 19.4°C to 25.5°C). December and January are the coolest months, with average temperatures of 17.5°C and 16.9°C respectively, and nighttime lows dropping to 14.5-14.4°C. In February, the temperature begins to gradually rise, reaching an average of 18.2°C (from 15.6°C to 20.8°C). Frosts are uncharacteristic for this region; the weather remains mild. Temperature fluctuations between day and night throughout the year are moderate, averaging from 4.7°C to 6.1°C, which ensures relatively stable temperature conditions during the day, with a slightly larger spread in cooler months such as November and December.

In Ha Long, there is a clear division of the year into two main seasons regarding precipitation: the dry season and the rainy season. Understanding these cycles will help better plan your trip, especially if you are planning boat trips or outdoor activities.

The dry season in Ha Long usually lasts from December to April. During this period, rainfall is minimal. January and December are the driest months, when only about 1 mm of precipitation falls, and the number of rainy days does not exceed 5-9. February, March, and April are also characterized by low precipitation levels (about 2 mm). Although the number of days with possible precipitation gradually increases by April to 14, these are usually insignificant and short-lived rains that are unlikely to seriously affect your plans.

The rainy season in Ha Long falls on the period from May to September, reaching its peak in the summer months. In May, the amount of precipitation noticeably increases to 6 mm, and the number of rainy days increases to 21. The highest amount of precipitation falls in August – about 15 mm, and this month is also the record holder for the number of rainy days, counting up to 28. June, July, and September are also quite wet, with rainfall in the region of 10-11 mm and more than 20 rainy days in each. Rains during this period often take the character of intense tropical downpours, which can be strong but often short-lived. October and November are transitional months when the amount of precipitation and rainy days gradually decreases (5 mm and 15 days in October, 2 mm and 10 days in November), signaling the approach of the dry season.

When planning a trip to Ha Long, it is important to choose your wardrobe correctly to feel comfortable in any weather. Given the subtropical climate of Vietnam, the key principle is layering and readiness for both sunny days and possible rain. Regardless of the season, be sure to bring comfortable shoes for walking and excursions, sunscreen, a hat, and sunglasses, as the sun can be active even in cooler months. A light insect repellent will also be useful, especially for evening walks.

If your trip falls during the cooler and drier season, which usually lasts from November to April, when average temperatures range from 17°C to 24°C and precipitation is minimal, you will need light trousers or jeans, T-shirts, long-sleeved shirts, and a light jacket or sweater for evening walks or cool days, especially in January and December. During this period, rains are rare, but a light windbreaker may come in handy.

For a trip during the hot and humid rainy season, from May to October, when average temperatures rise to 27-29°C and it rains often (especially from June to September), pack light, breathable clothing made from natural fabrics – cotton or linen. Shorts, tank tops, and sundresses will be perfect. Be sure to take a reliable umbrella or a light raincoat. Sandals or other water-resistant shoes will also be useful. Due to high humidity, clothes may take longer to dry, so several changes of outfits will be helpful. Regardless of the season, for cruises on Halong Bay, a light cardigan or windbreaker may be needed, as it can be breezy on the water.