Vietnam Weather in September 2027, Region by Region

Vietnam weather in September is good in the north and risky in the centre. Hanoi averages 32°C by day and 228 mm of rain, less than August's 309 mm, and the mountain rice turns gold. Hue and Da Nang start their storm season, with 351 to 411 mm. The south is hot and wet, with a shower most afternoons.

Vietnam weather September: the region table

All the figures below come from one dataset, the long-term station tables in Vietnam's national building climate standard, QCVN 02:2022/BXD. They are averages, not a forecast. The tables have no Hoi An, Phong Nha or Saigon station, so those rows borrow Da Nang, Dong Hoi and Can Tho.

The numbers that matter are in the rain column. Dong Hoi jumps from 166 mm in August to 473 mm in September, almost three times as much, and Hue goes from 139 mm to 411 mm. The north moves the other way. Hanoi's rain falls by about a quarter from August and drops again to 141 mm in October. The QCVN 02:2022 climate tables carry the decimals for every station.

A rain day is any day with measurable rain. Twenty-two of them at Can Tho usually means an hour of heavy rain in the late afternoon, not a lost day. For the other eleven months, see the best time to visit Vietnam.

Weather in Hanoi in September, and the north

Hanoi in the first week of September is still summer: 32°C, high humidity and thunderstorms that blow through in an hour. By the last week the mornings feel lighter. Hanoi has 162 hours of sun in the month, more than three times its 46 hours in March.

Typhoons still reach the north. Typhoon Bualoi came ashore in Nghe An on 29 September 2025, and its rain flooded low streets in Hanoi the next day. Leave a buffer day before an international flight out of Noi Bai. The same storms stop Halong cruises; our guide to Halong Bay weather by month lists the 2025 stoppages.

The reason to go north this month is the rice. In Mu Cang Chai, about 300 km and 6 to 7 hours north-west of Hanoi by road, the terraces usually turn gold from mid-September into early October. Sapa's valleys usually turn from mid-September too, and most fields are cut by early or mid October. The roads are wet, Sapa gets 20 rain days, and the trails up from Lao Chai and Ta Van turn to clay. Grippy shoes matter more than a heavy jacket, because Sapa nights only drop to about 16°C.

Tam Coc, about two hours south of Hanoi by road.

Ninh Binh is two hours south of Hanoi by road. Some of its paddies turn gold late in the month, but many fields along the Tam Coc boat route grow only the spring crop, cut around early June, so do not plan the day around golden rice there. Our Ninh Binh guide covers the boat routes. Halong averages 14 rain days at Bai Chay. Cruises are suspended when a storm warning is issued, which usually means one or two days lost rather than a week, and the Sapa or Halong Bay comparison helps if you only have time for one.

Central Vietnam in September: go early or keep it flexible

September is when the centre turns. In Da Nang the average rain goes from 141 mm in August to 351 mm, and in Hue from 139 mm to 411 mm. October is worse again at 628 mm and 773 mm, which is why Vietnam in October tells beach travellers to skip the centre. The first ten days of September usually still feel like summer. The last ten often do not.

When a storm comes, it shuts more than the beach. The night Bualoi hit, four central airports closed and hundreds of flights were cancelled or delayed. The storm left at least 54 people dead or missing across Vietnam. Hue had flooded streets and eroded river banks.

Hue after Typhoon Ketsana, which struck at the end of September 2009.

So book Hue and Hoi An with free cancellation, and put them early in the trip if the dates allow. Hoi An's old town floods when the Thu Bon River rises, usually from October, though a September storm can do it too. The Hoi An weather guide and the Da Nang weather guide go month by month.

Phong Nha in September: what still runs

Dong Hoi averages 473 mm of rain in September, 16 rain days and 31°C highs, almost three times its August rain. Expect high brown rivers, wet trails and a forest at its greenest. The Vietnam rainy season guide explains why the centre gets its rain so much later than Hanoi.

Three Jungle Boss tours close from September to November and reopen on 1 December: Bach Ma Discovery and the two Do Quyen Waterfall tours. Every other tour runs, and that includes every multi-day expedition, from the 2-day Ma Da Valley camp (VND 5,175,000) to the 3-day Tiger Cave Series and Hung Thoong trips and the 5-day Kong Collapse. A storm warning can still cancel a single date. When that happens Jungle Boss moves you to another day at no charge, offers a different tour, or refunds in full, so tell us your onward travel times when you book.

The Son River in Phong Nha, where most tours run through September.

The one-day Elephant Cave and Ma Da Valley trek is the cheapest group day tour from Phong Nha town at VND 1,950,000, about US$74, prices checked November 2026. It runs daily with pickup around 8:00 AM in Phong Nha or Dong Hoi, and takes children from 9. You walk into Elephant Cave, swim in Ma Da Lake and eat a grilled lunch by the water. The day normally ends with a swim through Tra Ang water cave, which runs more than 600 m, but from mid-September high water can pause that part. Ask when you book whether it is going ahead. Our Phong Nha travel guide covers getting there and where to stay.

The south: Saigon, the Mekong and Phu Quoc

The south sits around 31°C by day and 24°C at night all month. Rain comes on 22 days at Can Tho, mostly as a late-afternoon storm of 30 to 60 minutes. Do the outdoor sights before 2 pm and keep the museums for later.

The Mekong is high in September, which is good for the boats. Floating markets keep running and the orchards are heavy. Our Mekong Delta tour guide compares the day trips from Saigon.

The Mekong runs high in September, which suits the boats.

Phu Quoc is the weak spot. It gets 474 mm in September, its second-wettest month after August, and only 138 hours of sun. Rain falls to 164 mm in November and 59 mm in December, so save the island for later in the year. The Phu Quoc guide helps you choose a beach when you do go.

September festivals and holidays in 2027

National Day falls on Thursday 2 September 2027. The government has approved a 4-day break from 2 to 5 September, according to Viet Nam News. Domestic flights, sleeper trains and beach hotels sell out well ahead, so book any city-to-city move that week as soon as you have dates. The Vietnam train guide explains how to book a berth online.

Paper toy drums sell beside the lanterns on Hang Ma Street before Mid-Autumn.

The Mid-Autumn Festival falls on Wednesday 15 September 2027, the 15th day of the 8th lunar month. Hang Ma Street in Hanoi's Old Quarter fills with lantern and toy stalls in the weeks before it. The Mid-Autumn Festival guide has the details.

What to pack for September

• A light rain shell with a hood. Umbrellas are useless on the back of a motorbike.
• Quick-dry shirts and shorts. Cotton stays damp all day when average humidity runs 81% in Hanoi and 87% at Can Tho.
• Sandals for flooded streets, plus shoes that grip on wet stone.
• A fleece for Sapa and Mu Cang Chai, where nights drop to about 16°C.
• Insect repellent for the evenings. Mosquitoes breed in the standing water the rains leave, and the Mekong has plenty of it.

For a Phong Nha trek, leave waterproof boots at home. They fill with water at the first river crossing and never dry. Jungle Boss lends army boots in sizes 37 to 45.

Crowds and prices in September

September is low season across most of the country. The domestic summer rush ends in late August, so beaches on the central coast are quiet and hotels there discount. The exception is the 2 to 5 September holiday, when Vietnamese families travel and coastal rooms sell out. If your dates can move a month earlier, here is what Vietnam is like in August.

The northern harvest areas run against the trend. Homestays in Mu Cang Chai and the better rooms in Sapa book up for the second half of the month, so reserve a week or more ahead. Check the national weather service two or three days before any cruise, mountain pass or cave day.