Vientiane
Laos
| Season | Autumn | Winter | Spring | Summer | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Sep | Oct | Nov | Dec | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Year |
| Record high, °C | 35 | 35 | 35 | 35 | 36 | 37 | 37 | 39 | 38 | 36 | 35 | 35 | 39 |
| Average high, °C | 29 | 28 | 27 | 27 | 27 | 29 | 31 | 31 | 31 | 30 | 29 | 29 | 29 |
| Average temperature, °C | 26 | 25 | 24 | 22 | 21 | 24 | 26 | 27 | 28 | 27 | 27 | 27 | 26 |
| Average low, °C | 22 | 21 | 20 | 18 | 16 | 19 | 18 | 22 | 23 | 22 | 23 | 22 | 20 |
| Record low, °C | 17 | 16 | 12 | 10 | 7 | 12 | 12 | 15 | 20 | 17 | 20 | 20 | 7 |
| Rain, days | 16 | 7 | 3 | 0 | 0 | 0 | 2 | 5 | 5 | 17 | 19 | 20 | 94 |
| Average precipitation, mm. | 326 | 317 | 235 | 121 | 62 | 26 | 36 | 65 | 157 | 262 | 251 | 321 | 2181 |
| Relative humidity, % | 80 | 81 | 78 | 76 | 73 | 71 | 70 | 70 | 74 | 75 | 74 | 75 | 75 |
| Wind speed, km/h | 7 | 8 | 9 | 9 | 9 | 9 | 10 | 9 | 8 | 8 | 8 | 8 | 9 |
| Day Length, часов | 13 | 12 | 12 | 12 | 12 | 12 | 12 | 12 | 13 | 13 | 13 | 13 | 12 |
| Dew point, °C | 23 | 22 | 20 | 18 | 16 | 18 | 20 | 22 | 23 | 23 | 22 | 22 | 248 |
| Growing degree-day, °C | 489 | 477 | 426 | 384 | 353 | 384 | 490 | 522 | 549 | 522 | 536 | 533 | 5666 |
| Solar radiation, global, Mj/m2 | 15 | 15 | 14 | 14 | 17 | 18 | 19 | 20 | 18 | 16 | 15 | 15 | 16 |