Tomorrow's Weather Forecast - Vientiane

Tomorrow's weather in Vientiane. high 31°C (88°F), low 23°C (73°F). Drizzle.

Tomorrow’s Outlook

Tomorrow brings a similar temperature to today. Expect heavy rain in the afternoon, with rain chances climbing as high as 73%. That risk lines up with humidity averaging 75% through the day the more moisture in the air, the more readily clouds build into showers. Humidity stays high near 75%, so it will feel muggier and stickier than the temperature alone suggests. A light breeze near 14 km/h is expected. Sunrise is at 5:57 AM and sunset at 6:14 PM, for about 12h 18m of daylight.

Tomorrow
31°/ 23°
Today32° / 26°

Tomorrow’s Hourly Weather Outlook

Morning6 AM – Noon26°
Rain probability
3%
Wind speed
3 km/h
AfternoonNoon – 6 PM30°
Rain probability
73%
Wind speed
12 km/h
Evening6 PM – Midn27°
Rain probability
47%
Wind speed
4 km/h
NightMidn – 6 AM25°
Rain probability
0%
Wind speed
14 km/h

24-Hour Rain & Temperature Forecast

Tomorrow12 Sep
··
0:00
1:00
2:00
3:00
4:00
5:00
6:00
7:00
8:00
9:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00

Temperature · peaks at +31°C

Planning Advice for Tomorrow

Clothing
Waterproof jacket and umbrella strongly recommended.
Outdoor
Not ideal for outdoor plans or car washes — heavy rain expected.
Travel
Expect traffic slowdowns from wet roads. Allow extra time.

Sunrise & Sunset

Sunrise
Dawn 5:27 AM
Total Daylight
Full day forecastSolar noon 12:05 PM
Sunset
Dusk 6:44 PM
vs today-1 min daylight
Sunrise shift1 min later
Sunset shift1 min earlier

5-Day Weather Forecast

Full 15-Day Forecast

Weather Insight

Vientiane is forecast to reach a high of 31°C tomorrow, with an overnight low around 23°C. That's 1° above the long-term average high of 30°C for this time of year. Expect a high chance of rain (73% probability) and a gentle breeze averaging 14 km/h. Air quality is currently Moderate (AQI 77), driven mainly by O₃ at 104 μg/m³.

Today vs Normal

32°C+2° above normal

The long-term average high for today is 30°C.

14 of the last 28 days with published data ran above normal.

That's a break from the pattern - today's forecast runs above normal even though the recent stretch mostly ran below.

2026-08-28: 30°C30°2026-08-29: 27°C27°2026-08-30: 26°C26°2026-08-31: 30°C30°2026-09-01: 31°C31°2026-09-02: 32°C32°2026-09-03: 32°C32°2026-09-04: 30°C30°2026-09-05: 32°C32°2026-09-06: 31°C31°2026-09-07: 31°C31°2026-09-08: 32°C32°

Red = above normal, blue = at or below · last 12 days

Air Quality

Air Quality
Moderate

Air quality is acceptable for most people. Unusually sensitive individuals should consider reducing prolonged or heavy outdoor exertion.