September is the transitional time between summer and autumn in the North of Vietnam; between the hot and dry season and the rainy season in the Central Coast of Vietnam; the rainy season in the Central Highlands and South of Vietnam.
There could by tropical depressions or typhoons hitting the Central Coast or the North of Vietnam in September. The rain often gets heavier in the Central Highlands and South of Vietnam in September. During the time of a typhoon in the North of Vietnam and North of the Central Coast, cruises on Halong Bay are not allowed.
September may not be a great time for adventure tours in the far north of Vietnam due to more heavy rain which may cause landslides and flash floods.
The winds which affect Vietnam in September include:
- The Southeasterly Wind in the North of Vietnam which causes rain and nice temperatures. The North often experiences pleasant breezes during the month.
- Westerly/Southwesterly Wind in much of the Central Coast of Vietnam which is also known as the foehn wind that causes heat strikes in this region. This wind is not so prevalent in the Central Coast this month.
- Southwesterly Wind in the Central Highlands and the South of Vietnam which is moist and pleasant and which causes daily rain and nice temperatures. The wind is often strong this month and heavier rain is found in these two regions.
Both the Con Dao Islands and Phu Quoc Island often have more clouds and daily short-lived rain, pleasant temperatures (26-30oC) in September.
Below is our review of the weather in Vietnam in September 2020.
1/ The first week of September 2020 marked a heat strike in the North and Central Coast of Vietnam with mostly strong sun and daily high temperatures reaching 35-36oC in the North and 36-38oC in the Central Coast. The temperatures turned pleasant in the North coming toward the end of the first week while they remained high in the Central Coast throughout the week.
There was some rain in the far northern mountain but little rain in the Central Coast. There was more heavy rain in the Central Highlands and South of Vietnam. The temperatures were mostly pleasant in these two regions: 21-31oC and 24-34oC respectively.
2/ In the second week of September 2020, there was more heavy rain in the far-northern mountains, in the Central Highlands and in the South of Vietnam. There were several places in the Northeast and Northwest of Vietnam temporarily flooded (Cao Bang, Yen Bai, Lao Cai...). The temperatures were mostly pleasant in these regions.
The Central Coast remained warm in the second week of September 2020 but the temperatures were more tolerable. There was mostly sun and some isolated t-storms.
3/ The third week of September 2020 started with a low-pressure air trough forming in the East Sea which later turned into Typhoon No 5 in Vietnam in 2020. The Typhoon made landfall in Hue felling down tens of thousands of trees then brushed through Quang Tri into Laos. Torrential rain from Nghe An to Quang Ngai which made several cities temporarily flooded. There was a flash flood in Ky Son (Nghe An) killing livestock.
At the same time when the tropical storm was raging in the Central Coast, the first spell of Northeaster Monsoon (Winter Monsoon in northern Vietnam) made its way into the North. Heavy rain was found across the region and the temperatures turned pleasant.
There was more rain in most of the Central Highlands an South of Vietnam throughout the week.
4/ The last week of September 2020 was started by the arrival of the first spell of the Winter Monsoon in northern Vietnam which caused nice temperatures all over the region and which caused torrential rain in the far northern mountains for the first couple of days.
The Central Coast had more clouds and rain.
There was more rain in the Central Highlands and South of Vietnam.
