Climate averages 1991–2020
Vientiane weather
in May.
A hot, very wet month: the 3rd warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a hot month in Vientiane: daytime highs average 31.9°C and nights cool to about 24.7°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 261 mm of rain on roughly 23 days, which makes May a very wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 58 min on an average May day.
The nearest other city in this atlas is Udon Thani (64 km away). In May its highs average 32.6°C, 0.7°C warmer than Vientiane, with 211 mm of rain.
Among the 4 cities listed in Laos, Vientiane ranks joint 2nd of 4 for the warmest May highs and 4th of 4 for the driest May (rainfall, lowest first). The mean May high of those 4 cities is 31.9°C; Vientiane is 0.1°C warmer than that mean.
From May to June, average highs fall by 1.4°C to 30.5°C, and monthly rainfall rises from 261 mm to 316 mm.
The annual picture
May in context
Monthly rainfall
Average total · mmAverages 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
| 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, selected | 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 | 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
May in nearby cities
- Udon Thani in MayThailand · 64 kmHigh 32.6°C · Low 25.1°C · 211 mm rain
- Khon Kaen in MayThailand · 171 kmHigh 33.4°C · Low 25.4°C · 152 mm rain
- Sakon Nakhon in MayThailand · 187 kmHigh 32.2°C · Low 25.0°C · 216 mm rain
- Thakhèk in MayLaos · 244 kmHigh 31.5°C · Low 24.2°C · 253 mm rain
- Savannakhet in MayLaos · 277 kmHigh 32.1°C · Low 24.7°C · 189 mm rain
- Lampang in MayThailand · 330 kmHigh 32.8°C · Low 24.6°C · 168 mm rain
- Vinh in MayVietnam · 336 kmHigh 32.1°C · Low 25.4°C · 99 mm rain
- Nakhon Ratchasima in MayThailand · 337 kmHigh 33.5°C · Low 25.2°C · 140 mm rain
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 limitsHow 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.