If you plan to visit Vientiane in September, the weather is typically alright, with an average high temperature of +31°C during the day and approximately 0 sunny days. Expect some rainy, though, as there are typically 24 rainy days in the month and around 282 mm of precipitation. The weather is changeable so you may have to pack for every eventuality. Search flightsin one click on Avionero.
Average weather
☀️
+31°C
Avg. max. temperature
+21°C
Min.
+36°C
Max.
282 mm
Total precipitation
83%
Avg. humidity
0 m/s
Avg. wind
0 ☀️
Sunny Days
2 ⛅️
Cloudy
24 🌦
Rainy
Our opinion: Vientiane has OK weather in September.
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Average temperature in Vientiane in September
Here are the expected maximum, average and minimum temperatures in Vientiane for September based on the historical data.
Last Year
Historical Data
Going from a maximum of +35°C during the day to a minimum of +24°C during the night, the temperature in September averages around +32°C.
The average maximum temperature goes down 27% by the end of the month, compared with the beginning of the month, from +34°C to +31°C.
Is Vientiane warm or cold in September?
Vientiane is typically hot in September.
Maximum temperatures go up compared to the previous month from +31°C to +31°C. The minimum temperature also goes up from +25°C to +25°C.
Make sure that you pack your summer linen and swimming costumes; it’s probably going to be hot.
Take a look at how September is compared to other months in Vientiane:
Climate in Vientiane in September
Vientiane weather looks like this, on average, in September and the surrounding months.
August
September
October
Avg. temperature
+31°C
+31°C
+31°C
Min. temperature
+23°C
+21°C
+15°C
Max. temperature
+37°C
+36°C
+36°C
Rainfall
373 mm
282 mm
95 mm
Wind
1 m/s
0 m/s
0 m/s
Humidity
84%
83%
79%
Air pressure
1005 HPa
1007 HPa
1010 HPa
Sunny days
0
0
4
Cloudy days
1
2
9
Rainy days
27
24
17
Snowy days
0
0
0
September weather is still as ok as in August.The temperature levels stay the same in the area of +31°C for average maximum temperature during the day.As September arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 373 mm to 282 mm.It feels drier, as humidity decreases from 84% to 83%.Winds are calmer in comparison to August, going down from 1 m/s to 0 m/s on average.The amount of sunny days stay about the same, averaging 0 sunny days during the month.
October brings much the same weather, it remains ok.
Wind speed in Vientiane in September based on historical data.
Last Year
Historical Data
The average wind speed is 1 m/s getting up to 3 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in Vientiane is gradually decreasing during September, going from 1 m/s to 0 m/s over the course of the month.
Rain
Amount of rainfall in mm during September in Vientiane based on historical data.
Last Year
Historical Data
Typically, there is a 97% chance of rain on an average day in September, with total rainfall of approximately 439 mm. The maximum amount of rainfall per day is around 80 mm, which is considered heavy rain.September is a pretty wet month with over 29 rainy days, so don’t forget to pack an umbrella, raincoat, and a pair of galoshes.
Here’s how September is compared with other months in the amount of precipitation, total mm:
Vientiane wettest month is August, where a typical day has a 87% chance of precipitation and 373 mm of rainfall per day. December, on the other hand, is the driest month with a mere 6% chance of precipitation and 5 mm of rainfall per day.
How was the weather last September in Vientiane?
This is the weather in Vientiane in September 2024:
1 September
☁️
+34°C
2 September
☁️
+35°C
3 September
☀️
+35°C
4 September
🌧️
+33°C
5 September
☁️
+32°C
6 September
🌧️
+31°C
7 September
🌧️
+33°C
8 September
🌧️
+33°C
9 September
🌧️
+33°C
10 September
🌧️
+31°C
11 September
🌧️
+30°C
12 September
🌧️
+31°C
13 September
☁️
+30°C
14 September
🌧️
+32°C
15 September
🌧️
+29°C
16 September
🌧️
+30°C
17 September
🌧️
+29°C
18 September
🌧️
+30°C
19 September
☁️
+30°C
20 September
☁️
+34°C
21 September
☁️
+35°C
22 September
☁️
+34°C
23 September
☀️
+35°C
24 September
☁️
+34°C
25 September
🌧️
+34°C
26 September
🌧️
+28°C
27 September
🌧️
+29°C
28 September
🌧️
+29°C
29 September
🌧️
+29°C
30 September
🌧️
+31°C
In September 2024 Vientiane had 2 sunny days, 9 cloudy days, and 19 rainy days. The average maximum temperature was +32°C, with an absolute maximum of +35°C and a minimum of +28°C. The average humidity was 79%, with a maximum of 99% and a minimum of 51%. The average wind speed was 1 m/s, with a maximum of 5 m/s and a minimum of 0 m/s.
Are you planning a trip in September?
Climate Change over Years
This is how Vientiane climate have been changing during last 43 years period.
The climate in Vientiane in September has not changed much over the last 43 years.
The average temperature was the lowest in 1996 (+30°C) and the highest in 2019 (+33°C). The driest year was 2019 with only 1054 mm of rainfall, and the wettest year was 1994 with 2326 mm.
FAQ
Frequently asked questions about the weather in Vientiane in September:
Is September a good time to visit Vientiane?
It’s always a good time to visit Vientiane, but the weather is changeable in September, so plan a mix of indoor and outdoor activities and exploring, and pack for every eventuality.
Can you sunbathe in Vientiane in September?
Absolutely, September is hot in Vientiane. Plan on beach and pool time, and ensure that you pack light and breathable options to stay comfortable.
Is Vientiane rainy in September?
Vientiane is often rainy in September. You may get a bit damp when outside, so pack an umbrella, and maybe even a raincoat.
Is it sunny in Vientiane in September?
Usually, it’s not very sunny in Vientiane in September, often it’s pretty cloudy. Pack for any eventuality; layering can help reduce the number of bulky items needed.
For this page, we’ve looked at the typical weather in Vientiane, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.
