Climate averages 1991–2020

Vientiane weather
in July.

A hot, very wet month: the 5th warmest and the 11th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 29.9°C Daytime mean, July

Average low 24.4°C Night-time mean, July

Rainfall 372 mm 27 days with ≥1 mm

Daylight 13 h Sunrise to sunset, per day

July is a hot month in Vientiane: daytime highs average 29.9°C and nights cool to about 24.4°C. By daytime temperature it is the 5th warmest of the 12 months.

Expect about 372 mm of rain on roughly 27 days, which makes July a very wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 06 min on an average July day.

The nearest other city in this atlas is Udon Thani (64 km away). In July its highs average 30.6°C, 0.7°C warmer than Vientiane, with 266 mm of rain.

Among the 4 cities listed in Laos, Vientiane ranks 2nd of 4 for the warmest July highs and 2nd of 4 for the driest July (rainfall, lowest first). The mean July high of those 4 cities is 29.7°C; Vientiane is 0.2°C warmer than that mean.

From July to August, average highs fall by 0.3°C to 29.6°C, and monthly rainfall rises from 372 mm to 401 mm.

The annual picture

July in context

30-year average

Average highAverage low°C

Monthly rainfall

Average total · mm

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Vientiane climate table

1991–2020

Monthly climate averages for Vientiane, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	27.3°C17.0°C	17.0°C	11	1.8	11.211 h
February	29.8°C18.9°C	18.9°C	15	2.2	11.512 h
March	32.6°C22.1°C	22.1°C	36	6.2	12.012 h
April	33.8°C24.4°C	24.4°C	75	11.9	12.513 h
May	31.9°C24.7°C	24.7°C	261	23.4	13.013 h
June	30.5°C24.7°C	24.7°C	316	25.0	13.213 h
July, selected	29.9°C24.4°C	24.4°C	372	26.5	13.113 h
August	29.6°C24.1°C	24.1°C	401	27.4	12.713 h
September	29.6°C23.8°C	23.8°C	300	24.7	12.312 h
October	29.3°C22.7°C	22.7°C	101	11.9	11.712 h
November	28.7°C20.2°C	20.2°C	22	3.0	11.311 h
December	26.9°C17.3°C	17.3°C	8.4	1.2	11.111 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

July in nearby cities

Distance from Vientiane

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Vientiane) is explained once on the Vientiane year overview and on the Sources, method and limits page.