Halong Bay Weather in September: What to Expect

September brings a refreshing change to Halong Bay, blending cooler temperatures, gentle breezes, and occasional rain.

The Halong Bay weather in September sets the stage for serene exploration, with fewer crowds and tranquil surroundings.

From misty mornings to golden sunsets, September offers the perfect opportunity to discover the bay’s stunning limestone karsts, lush landscapes, and vibrant local life.

Whether you’re kayaking through caves, enjoying an overnight cruise, or capturing scenic views, the Halong Bay weather in September promises an unforgettable adventure.

September Weather Chart

🔴 : Good Weather

🌩: High Chance Of Storm

👤: Crowded

$: Higher Cost

Average Temperature:

• Highest: 30°C (86°F)
• Lowest: 22°C (71.6°F)
• The Halong Bay weather in September signals the end of summer and the beginning of autumn, bringing cooler temperatures and occasional rainfall. Average daytime temperatures range between 26°C and 30°C, while evenings cool down to about 22°C, creating comfortable conditions for outdoor activities.

Humidity: 72%

Humidity levels start to drop slightly compared to earlier summer months, making the Halong Bay weather in September ideal for adventures like trekking, kayaking, and overnight cruises.

Rainfall: 200 mm per month 

Rainfall remains significant, with an average of 200mm spread across 15 rainy days. However, showers are typically short and infrequent, often leaving the skies clear for exploration.

Average hours of sunshine per day: 6-7 hours

Chance of Storms: High Chance Of Storm 

With milder temperatures and refreshing breezes, September offers the perfect setting for enjoying Halong Bay’s iconic limestone karsts and emerald waters.

Pros:

• Peaceful low season atmosphere: September marks the start of the low season in Halong Bay. As the summer vacation ends and students return to school, both domestic and international tourist numbers drop. This means less crowded attractions, quieter cruises, and a generally more relaxing experience.
• Attractive prices and promotions: With lower demand, travel providers offer competitive deals. Visitors can enjoy discounted rates on hotels, cruises, and tour packages while still receiving high-quality service. It’s an ideal time for budget-conscious travelers who don’t want to compromise on experience.
  
• Stunning early autumn scenery: Halong Bay in September is especially scenic. The early signs of fall bring clearer skies, gentle breezes, and vibrant natural colors. The bay’s calm emerald waters and dramatic limestone formations are even more breathtaking in this light.
  
• Comfortable weather for outdoor adventures: The weather is warm enough for activities like swimming, kayaking, squid fishing, and visiting floating villages, but cooler and more pleasant than the peak summer months. It’s also a great time to enjoy sunset and sunrise views on an overnight cruise. 

Cons:

• Possibility of rain and tropical storms: September is part of the tail end of the rainy season. Sudden showers or occasional storms may occur, especially in the first half of the month. Travelers should keep an eye on weather forecasts and consider travel insurance for flexibility.
  
• Cruise cancellations may happen: Although rare, cruise trips can be delayed or canceled due to adverse weather. This can affect travel plans, particularly for those with tight itineraries. 

National Day (September 2)

This is Vietnam’s National Day, a major public holiday commemorating the country’s independence. Expect a short surge in domestic travel, especially around the long weekend if it falls near a Saturday or Sunday. Halong Bay may be slightly busier during this time, with more local tourists and celebratory activities.

Packing for Halong Bay weather in September requires versatile clothing to adapt to mild temperatures and occasional rainfall. Here’s what to include:

For daytime

Lightweight and breathable fabrics like cotton or linen to stay cool.

T-shirts, tank tops, and shorts are perfect for the warmer afternoons.

A sunhat, sunglasses, and sunscreen to protect against UV rays.

For evenings

A light sweater or cardigan for cooler nighttime temperatures.

Long trousers or casual pants for comfort and warmth.

Comfortable closed-toe shoes for evening excursions or walks on cruise decks

For water activities

Quick-drying swimwear or rash guards for kayaking and swimming.

Waterproof sandals or sturdy water shoes for navigating wet surfaces.

A lightweight rain jacket or poncho for sudden September showers.

The Halong Bay weather in September blends mild temperatures, occasional rain, and refreshing breezes, creating an ideal setting for both relaxation and adventure.

With fewer crowds and affordable travel options, September is perfect for exploring caves, tasting fresh seafood, and enjoying cultural experiences.