Vientiane climate

Name: Vientiane
Address: LA

Vientiane is warmest in April, with average highs of 34 °C, and coldest in January, when nights average 17 °C. August is the wettest month (409 mm) and December the driest (8.5 mm). Figures are 1991–2020 climate normals.

Across a full year Vientiane averages 1,929 mm of rain and 345 days above 25 °C.

Laos · population 840,940 · 1991–2020 normals

Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month

Warmest month April 34 °C
Coldest month January 17 °C
Driest month December 8 mm
Wettest month August 409 mm
Least cloud February 27 % cloud
Hottest on record April 40 °C
Coldest on record December 8.0 °C

What to expectVientiane through the year

Vientiane has a clear annual cycle: average daily highs run from 27 °C in January to 34 °C in April, a swing of 6.9 °C in mean temperature across the year.

Counted across a normal year, 345 days a year reach 25 °C, 174 of them reach 30 °C. The warmest reading in the 1991–2020 record is 40 °C, in April.

Rain is strongly seasonal. August averages 409 mm against 8 mm in December — 48 times as much. Planning around the dry months matters more here than planning around temperature.

Month by month

Month	Avg high	Rainfall	Cloud
January	27.3 °C	11 mm	32 %
February	29.7 °C	14 mm	27 %
March	32.4 °C	38 mm	35 %
April	33.7 °C	76 mm	50 %
May	31.8 °C	257 mm	78 %
June	30.5 °C	312 mm	92 %
July	29.9 °C	375 mm	92 %
August	29.6 °C	409 mm	92 %
September	29.6 °C	306 mm	80 %
October	29.3 °C	100 mm	57 %
November	28.6 °C	21 mm	37 %
December	26.9 °C	8 mm	33 %

Temperature month by month

Month	Avg high	Avg low	Mean	Record high	Record low	Days above 25 °C	Days above 30 °C
January	27.3 °C	16.8 °C	22.1 °C	34.5 °C	9.2 °C	25	4
February	29.7 °C	18.6 °C	24.2 °C	36.1 °C	10.4 °C	26	14
March	32.4 °C	21.8 °C	27.0 °C	39.3 °C	12.9 °C	30	25
April	33.7 °C	24.3 °C	28.8 °C	40.3 °C	16.2 °C	30	26
May	31.8 °C	24.6 °C	27.8 °C	39.6 °C	20.9 °C	31	23
June	30.5 °C	24.6 °C	27.2 °C	35.3 °C	22.6 °C	30	19
July	29.9 °C	24.4 °C	26.8 °C	36.7 °C	22.3 °C	31	16
August	29.6 °C	24.1 °C	26.4 °C	33.9 °C	22.1 °C	31	13
September	29.6 °C	23.7 °C	26.2 °C	33.5 °C	20.3 °C	30	13
October	29.3 °C	22.6 °C	25.7 °C	33.0 °C	15.6 °C	30	11
November	28.6 °C	20.0 °C	24.2 °C	33.4 °C	12.2 °C	28	7
December	26.9 °C	17.0 °C	21.9 °C	32.1 °C	8.0 °C	25	3

Rain, sun and wind month by month

Month	Rainfall	Wet days	Daylight	Cloud cover	Humidity	Wind
January	11 mm	2	11 h/day	32 %	65 %	11 km/h
February	14 mm	2	12 h/day	27 %	62 %	11 km/h
March	38 mm	6	12 h/day	35 %	62 %	11 km/h
April	76 mm	12	13 h/day	50 %	66 %	10 km/h
May	257 mm	23	13 h/day	78 %	78 %	9.3 km/h
June	312 mm	25	13 h/day	92 %	84 %	9.0 km/h
July	375 mm	27	13 h/day	92 %	85 %	9.5 km/h
August	409 mm	27	13 h/day	92 %	87 %	9.6 km/h
September	306 mm	24	12 h/day	80 %	86 %	8.0 km/h
October	100 mm	11	12 h/day	57 %	79 %	8.3 km/h
November	21 mm	3	11 h/day	37 %	70 %	9.1 km/h
December	8 mm	1	11 h/day	33 %	65 %	10 km/h

Planning a trip? See the best time to visit Vientiane.

QuestionsCommon questions about Vientiane’s climate

When is the best time to visit Vientiane?

That depends on what you want, so the honest answer is a comparison rather than a single month. January, November, December sit closest to 20 °C on average, April is the warmest month and December the driest. The month-by-month table above has the full picture.

How hot does Vientiane get?

In April, the warmest month, daily highs average 34 °C. About 174 days a year pass 30 °C. The highest value in the 1991–2020 record is 40 °C.

How cold does it get in winter?

Nights average 17 °C in January, the coldest month. Freezing nights are not part of a normal year here.

Which month is wettest in Vientiane?

August, averaging 409 mm over 27 days with rain. The driest month is December with 8 mm. The year as a whole averages 1,929 mm.

Are these figures a forecast?

No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Vientiane rather than what any particular week will bring. Individual years can differ substantially from the normal.

Data sources and method

ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
Open-Meteo — Open-Meteo.com. CC BY 4.0
NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
GeoNames — GeoNames.org. CC BY 4.0

Normal period: 1991–2020
Data point: 17.967°, 102.600° (the coordinates the reanalysis values are taken for)
Dataset version: era5-1991-2020-scores1.1
Last processed: 1 August 2026

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.