Vientiane, Laos Climate & Monthly Averages

Laos 🇱🇦 · tropical wet-and-dry climate
Annual avg
79°
Hottest month
April
Coldest month
January
Rainy days / yr
164
Sunshine
9.4 h/day
Right now: 78° and cloudy - see live conditions

The climate of Vientiane

Vientiane's year is organised around rain rather than temperature. 59% of its 76.7 inches (1948 mm) annual total arrives in the July to September window, while December averages 5 mm (0.2 in). Temperatures move far less: 94°F (34°C) at the year's warmest against 81°F (27°C) at its coolest.

Climate quick facts

  • Hottest month: April - highs near 94°F (34°C)
  • Coldest month: January - highs near 81°F (27°C)
  • Decade extremes (2015-2024): 108°F (42°C) high · 49°F (9°C) low
  • Wettest month: August (26 rainy days) · Sunniest: April (10.8 h sun/day)
  • Climate type: tropical wet-and-dry
  • Annual swing: 7°C between the average warmest and coolest month · day to night: 8°C
  • Months averaging 30°C or hotter: 7
  • Average humidity: 74%

Temperatures through the year

January sits at the other end of the year: 81°F (27°C) by day, 64°F (18°C) at night. At its warmest, in April, Vientiane runs to 94°F (34°C) in the afternoon and back to 76°F (25°C) by dawn. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 108°F (42°C) and the lowest daily minimum 49°F (9°C). Average highs hold at or above 30°C for 7 months of the year, March through September being the unbroken run.

Rain, sun and snow

Rainfall is strongly seasonal: 59% of the annual total falls in the July to September window, leaving December at 5 mm (0.2 in). 3 months average under 20 mm of rain, the longest unbroken stretch running December through February.

How Vientiane compares

  • 59% of the year's precipitation falls in its wettest three months - more seasonal than 91% of the 3496 cities we track.
  • Vientiane averages 79°F (26°C) across the year - warmer than 89% of the 3496 cities we track.

Ranked against every city in our dataset, each measured on the same ten-year window.

Monthly climate table

Monthly averages for Vientiane based on 2015–2024 weather data.
MonthHighLow Rain daysPrecipitation SunshineHumidity
January 81° 64° 2 0.7 in 10.0 h/day 66%
February 85° 66° 2 0.6 in 10.4 h/day 64%
March 90° 73° 8 1.9 in 10.5 h/day 66%
April 94° 76° 8 2.4 in 10.8 h/day 64%
May 91° 78° 22 8.4 in 9.6 h/day 76%
June 88° 77° 25 10.8 in 8.6 h/day 83%
July 87° 77° 26 14.6 in 7.8 h/day 85%
August 86° 76° 26 16.8 in 7.1 h/day 86%
September 86° 76° 26 13.9 in 8.4 h/day 86%
October 86° 74° 14 5.4 in 9.8 h/day 79%
November 85° 71° 3 1.1 in 10.1 h/day 70%
December 81° 65° 2 0.2 in 9.8 h/day 65%

Vientiane month by month

Vientiane weather in January

January brings highs around 81°F (27°C), lows near 64°F (18°C), about 2 wet days - typically the coldest month of the year in Vientiane.

Vientiane weather in February

February brings highs around 85°F (29°C), lows near 66°F (19°C), about 2 wet days.

Vientiane weather in March

March brings highs around 90°F (32°C), lows near 73°F (23°C), about 8 wet days.

Vientiane weather in April

April brings highs around 94°F (34°C), lows near 76°F (25°C), about 8 wet days - typically the hottest month and the sunniest month of the year in Vientiane.

Vientiane weather in May

May brings highs around 91°F (33°C), lows near 78°F (25°C), about 22 wet days.

Vientiane weather in June

June brings highs around 88°F (31°C), lows near 77°F (25°C), about 25 wet days.

Vientiane weather in July

July brings highs around 87°F (31°C), lows near 77°F (25°C), about 26 wet days.

Vientiane weather in August

August brings highs around 86°F (30°C), lows near 76°F (24°C), about 26 wet days - typically the wettest month of the year in Vientiane.

Vientiane weather in September

September brings highs around 86°F (30°C), lows near 76°F (24°C), about 26 wet days.

Vientiane weather in October

October brings highs around 86°F (30°C), lows near 74°F (23°C), about 14 wet days.

Vientiane weather in November

November brings highs around 85°F (30°C), lows near 71°F (21°C), about 3 wet days.

Vientiane weather in December

December brings highs around 81°F (27°C), lows near 65°F (18°C), about 2 wet days - typically the driest month of the year in Vientiane.

Seasons in Vientiane

March through May

March through May in Vientiane runs at full heat, with daytime highs averaging 92°F (33°C) and nights around 76°F (24°C); rain falls on around 38 of the 90 days. Daylight is generous - around 10.3 hours of sun a day. With the moisture factored in, afternoons feel hotter than the reading suggests - the humidity and dew point converter shows why.

June through August

Through June through August, Vientiane runs hot: 87°F (31°C) by day, 77°F (25°C) after dark, and rain falls on around 78 of the 90 days.

September through November

September through November sits firmly in the heat here - highs near 86°F (30°C), nights near 73°F (23°C), and rain falls on around 43 of the 90 days.

December through February

Through December through February, Vientiane runs hot: 82°F (28°C) by day, 65°F (18°C) after dark, and precipitation is sparse, near 1.5 inches (39 mm) for the season. Daylight is generous - around 10.1 hours of sun a day.

Climate questions, answered

How cold does Vientiane get in winter?
January nights average 64°F (18°C). Cold never really arrives.
How warm is Vientiane on average?
79°F (26°C) across all twelve months - about 87°F (30°C) by day and 73°F (23°C) after dark.
How humid does Vientiane get?
Relative humidity averages 74% across the year, which reads as fairly humid. Paired with April heat, muggy afternoons are routine.
When is the dry season in Vientiane?
3 months average under 20 mm of rain, with December the driest at 5 mm (0.2 in).
How sunny is Vientiane?
9.4 hours a day averaged over the year, peaking in April at 10.8 hours.
Is Vientiane warmer or cooler than most cities?
Its 79°F (26°C) annual average is warmer than 89% of the 3496 cities in our dataset, which are all measured on the same 2015-2024 basis.

Best time to visit Vientiane

The best time to visit Vientiane is generally November to March, when the rains have stopped and the heat has not yet peaked. Daytime temperatures in that window sit near 85°F (29°C), with rain on about 3 days a month. For the same question asked the other way round, see where else is warm in November.

Pack for Vientiane with lightweight, breathable clothing and serious sun protection and proper waterproofs rather than an umbrella - wet days are the norm here. Even in April, lows of 76°F (25°C) make an extra layer worth the space.

Vientiane temperature records (2015-2024)

Highest recorded
108°
in May
Lowest recorded
49°
in January
Annual precipitation
76.7"
Snowy days / yr
0

Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.