September is autumn in Northern Vietnam, about to be the rainy season in the Central Coast, high rainy season with pleasant temperatures in the Central Highlands, Southern Vietnam.
There may be typhoons or tropical depressions which often disrupt holidays and tours in Northern Vietnam and sometimes in the North of the Central Coast of Vietnam. In these cases, boat trips on Halong Bay are often banned and torrential rain may cause flash floods and landslides, rock slides in the far northern mountains.
In the Central Highlands and Southern Vietnam, there is more long-lasting rain. Be extra cautious if you take part on a flooded road with running water and open sewage. Exercise good care if you travel to the Central Highlands as heavy rain poses fatal threats from flash floods and landslides.
General Weather Patterns in Vietnam in September
In September there are two main monsoons affecting Vietnam:
- The Northeast, Northwest and lowland of Northern Vietnam often have the Southeasterly Wind which brings along moisture and which makes the temperatures pleasant. The wind often causes high precipitations in these regions in September.
- The remainder of the country including the Central Coast, the Central Highlands is to have the Southwesterly Wind. This wind causes rain in the Central Highlands and Southern Vietnam but causes dry heat and high temperatures in the Central Coast due to the foehn effect. September is often the high rainy season in the Central Highlands and Southern Vietnam and the temperatures are just pleasant.
Beacause of the monsoons, it rains a lot in the mountains in far Northern Vietnam, in the Central Highlands and Southern Vietnam which may cause places flooded temporarily or flash floods in the mountains.
It is normal that the Central Coast of Vietnam are to undergo series of heat strikes when the Southwesterly Wind is more active due to the foehn effect, but in September this is not the case. The reason is that the Intertropical Convergence Zone is moving southward and more rainfalls are deposited in Northern Vietnam, the temperatures in Northern Vietnam get much cooler than in the summer and more cool air masses which move southward or southwestward. The ocean does not get heated as much as inland either.
So, there are other winds which are in conflict or change the direction of the otherwise prevalent wind – the Southwesterly Wind in the Central Coast. In reality, the Central Coast will have no wind or northerly wind or southerly wind or northwesterly wind. Without wind, it is slightly warm in the Central Coast and in the case if the latter winds, it rains and the temperatures get lower.
When more and more cool air masses form and move southward, the North of Vietnam enters the winter time, the Central Coast of Vietnam enters the rainy season. When the cool air masses are cool enough and the winds are strong enough, the Central Highlands and the South of Vietnam enters the dry season.
What to expect from your holidays to Vietnam in September, where to go in Vietnam in September?
Taking the general weather conditions in Vietnam into consideration, for those travelers planning holidays to Vietnam or those who are on vacations in Vietnam in September, then there may be some notes as follows:
- Those planning an adventure tour, a sightseeing trip, a family vacation in the far northern mountains of Vietnam in September should expect heavy to torrential rain which may disrupt your travel plan.
Trekking trails are often muddy, slippery and those embark on adventure trips should exercise top caution. On several trekking tours, you will have to walk through bodies of running water or streams or rivers with running waters. Rocky and/or dirt paths turn extremely slippery.
- Landslides, flash floods may take place in Cao Bang, Ha Giang, Yen Bai, Mu Cang Chai, Lao Cai, Sapa, Lai Chau, Dien Bien, Son La and Hoa Binh. Be careful with Route 32 at Mu Cang Chai. Rockslides may take place anywhere which have continual rain for a few days and which have vertical or steep rock cliffs. The route to the Muong Hoa Valley in Sapa or Route 6 at the Thung Khe Pass between Mai Chau and Tan Lac Districts of Hoa Binh Province may have rockslides.
- Families on vacation to Vietnam in the Central Coast are prepared to have days with clouds and days with rain in the Central Coast of Vietnam. The temperatures may be slightly warm on some days with the highest temperatures around 34-35oC, but mostly they are around 30-33oC.
- When it is dry, September is a good time for junk cruises on Halong Bay as it is often clear skies and soft lighting : you have lovely photos of the islands. But there may be tropical depressions or typhoons in September during the time Northern Vietnam under the impact of which, cruises or boat trips on Halong Bay are not allowed for a few days before, during and right after each typhoon.
- September is not a good time for bird watching tours as migratory bird species are not present in Vietnam yet, and bird parks and national parks in Vietnam are not busy with wildlife yet. Things start to get better from mid of September as cool air masses initiated bird migrations – the Fall Migration.
- September is not a great time to go for beach holidays or for island vacations in Vietnam. Still, you may enjoy some nice days in the South of the Central Coast (Ly Son Island, Quy Nhon Beach, Phu Yen Tuy Hoa, Phan Rang Ninh Chu Beach).
- The weather is not that nice on the Con Dao Islands and Phu Quoc Island in September. It rains more, more cloudy and gloomy skies. Besides, the active Southwesterly Wind may cause rough sea.
Below you can find Paradissa’s reviews and statistics of the weather in different regions in Vietnam in September 2023
On 28-August-2023, Northern Vietnam received the first cool air masses which caused some brief rain in the North and some rain in the Central Coast 1-2 days later. Cool air masses are associated with the Northeasterly Wind which caused cold winter in Northern Vietnam. Thanks to the cool air, Northern Vietnam entered September full of autumnal vibe : bright sunshine, lovely breezes, blue skies...
The Central Coast of Vietnam seemed to be entering the rainy season which is about just right seasonally. And there was heavy rain in the Central Highlands and Southern Vietnam as September 2023 begun which was just about right seasonally, too !
September should have been the flood season in the Mekong Delta, season of abundance. But in 2023, the water levels were much lower than usual (nearly 1m lower at Tan Chau An Giang). Lower water levels of the Mekong River result in serious lack of fresh water for agriculture as well as for family daily use, and huge problem with saltwater intrusion in the Mekong Delta. This is all attributed to hydro power dams in China.
The Saola Typhoon was raging in the East Vietnam Sea but far to the northeast and had no impact on the weather in Vietnam except slight warmth in the northern region. A visible impact of Typhoon Saola was that all speedboat trips were canceled between the inland and the Phu Quoc Island, Nam Du Island on 2-September-2023, Vietnam national holidays. Speedboats between Rach Gia and the Hon Son Island were not affected.
Rainfalls measured in 13 hours (from 19:00 of 1-September-2023): Xã Hiếu (Kon Tum) 97.8mm, Đạ Mri (Lâm Đồng) 53.8mm, An Phúc (Bạc Liêu) 55.4mm, Thới Bình (Cà Mau) 73.8mm,…
Rainfalls measured in 13 hours (from 19:00 hours of 3-September-2023): Măng Cành (Kon Tum) 152.6mm, TP. Buôn Ma Thuột (Đắk Lắk) 45.6mm, Thủy Điện Sê San (Gia Lai) 41.6mm,...
Regional weather patterns in Vietnam at the beginning of September 2023:
- Northeast: sun, clouds, 22-33oC;
- Northwest: sun, clouds, 23-34oC in Hoa Binh, Yen Bai, 26-36oC in Lao Cai; 22-32oC in Son La, and Lai Chau, 22-34oC in Dien Bien ;
- Lowlands: sun, clouds, 24-35oC.
- North of the Central Coast: sun, some clouds, isolated rain, 26-34oC;
- Central Coast from Quang Binh to Hue: sun, clouds, isolated rain, 26-36oC ;
- Central Coast from Da Nang to Quang Ngai: clouds, rain, 25-35oC;
- Central Coast from Quy Nhon to Tuy Hoa: sun, clouds, 26-36oC ;
- Central Coast in Khanh Hoa: rain, clouds, 26-34oC ;
- Central Coast Ninh Thuan: rain, clouds, 26-34oC ;
- Central Coast Binh Thuan: rain, clouds, 26-31oC ;
- Central Highlands: rain, 22-29oC mostly, 21-27oC in Pleiku;
- East of Southern Vietnam (Ho Chi Minh City, Dong Nai, Binh Duong, Binh Phuoc, Tay Ninh): clouds, rain, 25-32oC;
- West of Southern Vietnam ( The Mekong Delta): clouds, rain, 24-29oC.
Heading into the mid of September 2023, it rains all over Vietnam. The rain alternated by cloudy days with pleasant temperatures in Northern Vietnam gradually brough the full autumn vibe to the North by mid month. The rainy season had entered the Central Coast of Vietnam. The Central Highlands and Southern Vietnam entered the high rainy season with mostly gloomy and dark skies.
Rainfalls measured in 13 hours (from 19:00 of 13-September-2023): Thanh Mai (Bắc Kạn) 135m, Bản Sen (Quảng Ninh) 254.7mm, Trung Hội (Thái Nguyên) 123.4mm,…
Rainfalls measured in 6 hours (14-September-2023): Cửa Ông 145mm, Bản Sen 181mm (Quảng Ninh), Mai Đình 77mm, Tiên Sơn 76mm (Bắc Giang).
Rainfalls measured in 6 hours (14-September-2023): Phú Thành 79mm (Đồng Nai); Tân Phước 68.4mm (Bình Thuận)…
Rainfalls measured in 6 hours (14-September-2023): Yên Thắng 62mm, Yên Khương 59,8mm (Thanh Hóa); Sơn Màu 57,2mm (Quảng Ngãi)…
Rainfalls measured in 13 hours (14-September-2023): Mẫu Sơn (Lạng Sơn) 74.4mm, Quan Hoa (Hà Nội) 157.6mm, Tà Lương (Thừa Thiên Huế) 101mm, Đức Hòa (Long An) 93.6mm, Hòa Hiệp (Bà Rịa-Vũng Tàu) 90mm, Phú Thạnh (Đồng Nai) 86.8mm,…
Rainfalls measured in 8 hours (from 19:00 hours of 14-September-2023): An Lạc (Hòa Bình) 93mm, Đồng Giao (Ninh Bình) 94.6mm, Phúc Do (Thanh Hóa) 114mm,…
Regional weather patterns in Vietnam in mid of September 2023:
- Northeast: rain, clouds, 23-31oC;
- Northwest: rain, clouds, 23-31oC in Hoa Binh, Yen Bai ; sun, clouds, rain, 25-34oC in Lao Cai; sun, clouds, rain, 21-31oC in Son La, 21-32oC in Lai Chau, Dien Bien ;
- Lowlands: rain, clouds, 25-31oC.
- North of the Central Coast: rain, 26-31oC;
- Central Coast from Quang Binh to Hue: rain, 25-32oC ;
- Central Coast from Da Nang to Quang Ngai: rain, 25-33oC;
- Central Coast from Quy Nhon to Tuy Hoa: sun, clouds, rain, 26-35C ;
- Central Coast in Khanh Hoa: rain, clouds, 26-34oC ;
- Central Coast Ninh Thuan: rain, clouds, 25-34oC ;
- Central Coast Binh Thuan: rain, clouds, 25-33oC ;
- Central Highlands: rain, 22-30oC mostly, 21-28oC in Pleiku;
- East of Southern Vietnam (Ho Chi Minh City, Dong Nai, Binh Duong, Binh Phuoc, Tay Ninh): rain, 25-32oC;
- West of Southern Vietnam ( The Mekong Delta): rain, 24-31oC.
Coming towards the end of September 2023, there was more rain in the North and Central Coast of Vietnam, the Central Highlands and Southern Vietnam remained in the rainy season but less heavy rain.
There was a tropical depression hitting the coast of Quang Tri – Da Nang on 26-September which in combination with the Intertropical Convergence Zone caused heavy torrential rain across the North and part of the Central Coast. Flash floods were found in northern mountains. And floods were found in the provinces : Thanh Hoa, Nghe An, Ha Tinh, Quang Binh and Quang Tri. Floods and flash floods caused life and serious damage to houses as well as agricultural crops.
Landslides took place in the northern mountains and Ho Chi Minh Road, which passes through the provinces from Thanh Hoa to Quang Tri, had places underwater.
Rainfalls measured in 8 hours from 19:00 hours of 27-September : Mường Xén (Nghệ An) 88.4mm, Đậu Liêu (Hà Tĩnh) 86mm,...
Rainfalls measured in 24 hours from 20:00 hours of 27-September : Sao Vàng 153,6 mm(Thanh Hóa), Kỳ Anh 110 mm (Hà Tĩnh), Văn Chấn 112,8 mm (Yên Bái), Sa Pa 123,4 mm(Lào Cai), Phù Yên 100,2 mm (Sơn La), Đà Bắc 111,2 mm (Hòa Bình);…
Rainfalls measured in 6 hours on 28-September : Đồn Biên Phòng 571 53,6mm ( Hà Tĩnh); Khâm Đức 60mm (Quảng Nam),…
Regional weather patterns in Vietnam coming toward to end of September 2023:
- Northeast: rain, clouds, 23-32oC;
- Northwest: rain, 24-32oC in Hoa Binh, Yen Bai , Lao Cai; rain, 22-31oC in Son La, Lai Chau, Dien Bien ;
- Lowlands: sun, clouds, rain, 25-32oC.
- North of the Central Coast: rain, 25-31oC;
- Central Coast from Quang Binh to Hue: rain, 24-32oC ;
- Central Coast from Da Nang to Quang Ngai: rain, 25-32oC;
- Central Coast from Quy Nhon to Tuy Hoa: sun, clouds, rain, 25-32C ;
- Central Coast in Khanh Hoa: rain, 25-32oC ;
- Central Coast Ninh Thuan: rain, 24-33oC ;
- Central Coast Binh Thuan: rain, 24-32oC ;
- Central Highlands: rain, 21-30oC mostly, 21-29oC in Pleiku;
- East of Southern Vietnam (Ho Chi Minh City, Dong Nai, Binh Duong, Binh Phuoc, Tay Ninh): clouds, rain, 24-33oC;
- West of Southern Vietnam ( The Mekong Delta): rain, 24-32oC.
Disclaimer: Vietnam weather summary is for reviews of Vietnam weather by month on the basis as “it is” to the best of our knowledge. Paradissa does not guarantee the accuracy of our monthly reviews of Vietnam Weather. Our Vietnam Weather Reviews by month must not be used for making travel decisions or for any other purposes. Paradissa disclaims any liability in connection with with the use of our information.
