Ha Long weather by month in 2026

Below: a month-by-month weather table with air and water temperatures, rainfall and typhoon risk. Plus the practical calls — when to cruise, when the water is warm enough to swim, and when you are better off picking a different part of Vietnam altogether.

Climate data: climatestotravel.com, weather-and-climate.com and the NCHMF of Vietnam. Last checked March 2026.

Ha Long climate — the short version

Ha Long sits in the northeast of Vietnam, in Quảng Ninh province, on the Gulf of Tonkin. The climate is subtropical monsoon, and here is what sets it apart from the south, where it is 30°C all year round: winter is real. Not "a little cool after dark" but 15–16°C (59–61°F) at night and a jacket on deck.

Two monsoons run the show:

• Northeast monsoon (October–April) — cool and dry. 18–26°C (64–79°F), little rain, morning fog over the bay. Around 290 mm of rain across the whole season.
• Southwest monsoon (May–September) — hot and wet. Up to 33°C (91°F), heavy rain, humidity of 81–85%, and typhoons possible from July. Around 1,000 mm of rain.

Hạ Long Bay has been on the UNESCO list since 1994 — 1,969 limestone islands spread across 1,553 km². In winter the karsts vanish into a milky fog; in spring they gleam in the sun; in summer a tropical downpour drowns them.

The annual average is 26°C (79°F) with about 1,200 mm of rain. For comparison: Nha Trang gets roughly 1,300 mm, Ho Chi Minh City about 1,950 mm.

Planning a cruise? Here the weather is not background — it is the whole condition. When a typhoon warning is up, the bay closes, and no amount of money will get a boat out to sea.

Ha Long weather month by month — the summary table

Air: from 18°C (64°F) in February to 33°C (91°F) in July and August. Water: from 17°C (63°F) in winter to 30°C (86°F) in summer. Rainfall: from 20 mm in December to 334 mm in August.

Winter in Ha Long: December, January, February

Winter in Ha Long is not a beach trip. Days run 18–22°C (64–72°F), nights drop to 15°C (59°F). The water is 17–20°C — too cold to be pleasant. But it barely rains: only 20–30 mm a month.

December

The driest month: 20 mm of rain. Days 22°C (72°F), nights 17°C (63°F). It can be cloudy, but actual rain is rare.

If a tan is not your priority, December delivers. Few tourists, cruises 10–15% cheaper, and the bay is quiet — you can count the boats on one hand.

January

The coldest month. Days 20°C (68°F), nights 16°C (61°F). Mornings bring a dense fog over the bay, cutting visibility to 200–300 metres.

Some travellers find it a nuisance; others come to Ha Long in January precisely for the "foggy bay" — the karsts surfacing through the haze, the junks barely visible, photos that look like film stills. By midday the fog usually lifts.

Swimming? Only if you like a shock. The water is 18°C (64°F) — this is not Nha Trang.

February

The coldest by the averages: 18°C (64°F) by day, 15°C (59°F) at night. Fog is less frequent than in January but still shows up. Rainfall 30 mm.

February usually catches Tết, Vietnamese Lunar New Year. Hotel and cruise prices jump 20–30% and locals travel en masse across the country. If your dates land on Tết, book everything well ahead.

💬 "We did Ha Long Bay in late February — foggy in the morning, sunny by lunch. A jacket is a must. But almost nobody around, and a cruise for two came to about 3 million dong (~$120)." — traveller reviews on Tripadvisor, 2025

Spring in Ha Long: March, April, May

Spring is the best time to visit Ha Long if you want to combine comfortable weather, thin crowds and fair prices. Temperatures climb from 22°C (72°F) in March to 30°C (86°F) in May; the rain picks up, but the full monsoon is still a way off.

March

Averages around 22°C (72°F). The fog lifts, the sky clears. The water is 19°C (66°F) — too cold to swim, but perfect for kayaking and cruising.

March is one of the best months for photographers: clean air, soft light, the karsts at their finest. And noticeably fewer tourists than in October and November.

Want a full breakdown of the town itself? See our guide to Ha Long — districts, transport and where to stay before you arrive. (Full guide: Ha Long city guide.)

April

Days rise to 26°C (79°F), the water warms to 23°C (73°F). You can swim — at least on the sheltered island beaches. Rainfall of 80 mm means 10–12 days, usually short afternoon showers.

April is arguably the most comfortable month. Not hot, not cold. Clear days with blue skies. Cruise companies run on a normal schedule, and weather cancellations are almost unheard of.

May

The first genuinely hot month: 30°C (86°F), with humidity rising. Rainfall is already 160 mm — 12–14 rainy days. But the rain is still brief rather than drawn out.

May is the last chance to catch good weather before the summer monsoon. The water is 26°C (79°F) — proper summer. Prices have not yet dropped to their low-season floor, but they are already below peak.

Summer in Ha Long: June, July, August

Summer is the tricky season. Hot (32–33°C / 90–91°F), humid (up to 85%), wet (222–334 mm a month). From July, typhoons join in. On the upside, cruise prices fall 10–20% and the water is a perfect 29–30°C (84–86°F).

June

32°C (90°F), 222 mm of rain, 14–16 rainy days. The monsoon has started but not at full strength. Rain tends to come in the afternoon — you can still fit a morning excursion in.

Cruises run. Weather cancellations happen but are rare — roughly 1–2 days across the whole month. If you go in June, plan on the "morning on deck, evening in the air-conditioned cabin" strategy. The humidity presses, but the sunset views after a storm are their own kind of beautiful.

July

Peak rain: 302 mm, 15–17 rainy days. The mugginess is real — 33°C (91°F) at 84%+ humidity. Air conditioning in the cabin is not a luxury but a necessity.

Typhoon season opens. The chance of a storm warning in July is about 10%. Get lucky and you will see spectacular stormy sunsets over the karsts. Get unlucky and your cruise is rescheduled.

August

The wettest month: 334 mm of rain, 16–18 rainy days. Typhoon probability around 20%. Also one of the hottest — averaging 33°C (91°F).

Honestly: if you have a choice, do not plan Ha Long for August. The risk of a cruise cancellation is real, and losing one or two days of a three-day trip stings.

The one plus is price. A cruise for two can go 15–20% cheaper than in October.

Autumn in Ha Long: September, October, November

Autumn is Ha Long's golden season. From October the weather turns ideal: dry, warm, sunny. The water is still warm from summer. This is exactly when the cruise season peaks.

September

A transitional month. Rain is still 200 mm (12–14 days) and typhoons remain possible — around 15% risk. But temperatures are comfortable: 31°C (88°F) air, 28°C (82°F) water.

September is a lottery. You might get a cloudless week or three straight days under downpours. If your dates are flexible, you can gamble and land a low-season price with high-season weather.

October

Here it is — the golden month. Averages 28°C (82°F), rainfall 55 mm (6–8 days, usually short). Blue skies, excellent visibility, water at 26°C (79°F) — still swimmable.

October is the most popular month with tourists, and it shows: more boats in the bay, prices at their peak. Book your cruise at least 2–3 weeks ahead.

October is when Ha Long Bay looks like the postcards — emerald water, green karsts, cloudless skies. Kayaking, swimming off the boat, an overnight on the water — everything runs without limits. If you can pick only one month for Ha Long, make it October.

November

25°C (77°F) air, 24°C (75°F) water, 40 mm of rain. Another excellent month — slightly cooler than October, but with fewer tourists.

November is the last month when swimming in the bay is comfortable. From December the water cools to 20°C (68°F).

When to visit Ha Long

The ideal month depends on why you are going. Here are the specifics:

The worst time is August. Hot, wet, typhoons. If your dates are not fixed, shift at least to September or October.

One more thing: if you plan to pair Ha Long with other spots up north — Ninh Bình or Sa Pa — remember the mountains and the coast run different weather. Sa Pa can hit 5°C (41°F) in January while Ha Long is at 16°C (61°F). Dress in layers.

Best time for a Ha Long Bay cruise

A cruise on Vịnh Hạ Long is the whole reason people come to Ha Long. And the weather is the deciding factor: when a storm warning goes up, the bay closes to navigation entirely and no cruise runs at all.

October–November: the absolute top. Clear skies, water at 24–26°C (75–79°F), little rain. The bay at its best. The downside is peak prices and lots of boats.

March–April: the spring option. A touch cooler, but clear water and few tourists in March. By April it is warm enough to swim off the boat.

December–February: the atmospheric fog cruise. For those who want a different Ha Long — quiet, mystical, crowd-free. 18–22°C (64–72°F), jacket required.

June–September: the risky season. Cruises run, but storm cancellations are real — especially in July and August. The upside is discounts.

Cruise prices by season

Prices per person, based on double occupancy. Rate used: ~25,000 VND = $1 (March 2026).

Typhoons and storms — when the bay closes

Typhoon season in Ha Long runs from July to September, peaking in August. This is northern Vietnam, and typhoons here are a real threat, not a theoretical one.

What happens during a typhoon:

• The bay authority closes navigation. Every cruise is cancelled — no exceptions.
• Winds of 100+ km/h, waves of 3–5 metres.
• The closure can last 1 to 3 days.

How to cut the risk:

1. Plan a 3+ day trip — if one day is lost, the others remain.
2. Book a cruise with flexible cancellation (most 4–5★ operators offer a reschedule or a 50–100% refund).
3. Take out travel insurance that covers "weather-related cancellation."
4. Track the forecast 5–7 days out on Windy or AccuWeather.

Stuck in Ha Long because of a storm? The town is not empty: there is the Hạ Long Night Market, the Bãi Cháy cable car (ticket around 300,000 VND, ~$12), the Sun World Hạ Long water park and dozens of cafés along the promenade. A day without the sea is not a lost day.

What to pack — a checklist by season

Foreign travellers often overlook two small things: layers for the boat deck (even in shoulder season the wind off the water is cool) and cash. Cruise operators and street stalls around the pier frequently do not take cards, so carry enough dong for the trip.

FAQ

What's the weather like in Ha Long in March?

In March the average is about 22°C (72°F), with the water around 19°C (66°F). Rainfall is ~40 mm — roughly 8–10 rainy days, usually short. The morning fog typical of winter has cleared by March. It is one of the best months to cruise: comfortable temperatures, few tourists, good visibility.

Can you swim in Ha Long Bay in winter?

Technically yes, but the water at 17–18°C (63–64°F) in January and February will not thrill most people. Comfortable swimming needs 23°C+ (73°F+), which means April through November. In winter, focus on cruises, caves and kayaking, and save the beach days for southern Vietnam — say Nha Trang or Phu Quoc, where it is 28–30°C (82–86°F) in winter.

Are there typhoons in Ha Long Bay?

Yes. Typhoon season runs July to October, peaking in August (~20% chance). When a storm warning is issued, navigation closes completely: cruises are cancelled and boats are not allowed out. A typhoon averages 1–3 days. Most operators offer date changes or a partial refund. The advice — do not put your cruise on your only day in Ha Long, so you keep a buffer.

Which month has the warmest water in Ha Long?

The warmest water is in July and August: 30°C (86°F). From June to September it stays at or above 28°C. But those are exactly the months of peak rain and typhoons. The best compromise: May (water 26°C, rain still moderate) or October (water 26°C, excellent weather).

Is it worth visiting Ha Long in the rainy season?

It depends on how much risk you will accept. Upside: prices 10–20% lower, fewer tourists, perfectly warm water. Downside: downpours, humidity and a possible cruise cancellation. Go in June or September and your odds of good weather are better than in July–August. The key — book a cruise with flexible cancellation and keep a rain-day backup plan.

Which month is cheapest for a Ha Long Bay cruise?

Prices are lowest from June to September, when operators run 10–20% discounts to pull in off-season travellers. A day cruise can go from 1,200,000 VND (~$48). The most expensive periods are October and the days around Vietnamese New Year (Tết), when prices climb 20–30%.