Sơn La in Summer
In summer (June, July and August), Sơn La sees average daytime highs around 29°C and overnight lows near 23°C, with 780 mm of rain over about 73 wet days across the season. It is the warmest season of the year and the wettest season of the year.
Across summer, daytime highs hold fairly steady around 29°C. The sky is clear or mostly clear about 5% of the time across summer, and the air most often feels oppressive.
Summer is Sơn La's weakest season of the year to visit on our travel score. For the whole year in context, see Sơn La's year-round climate.
- Avg daytime high
- 29°C
- warmest season of the year
- Avg overnight low
- 23°C
- Rainfall
- 780 mm
- 73 wet days
- Avg wind
- 4 km/h
- Travel score
- 3.3
- weakest season of the year
- Months
- Jun · Jul · Aug
Temperature in Sơn La in Summer
Across summer, daytime highs hold fairly steady around 29°C.
A typical summer day in Sơn La reaches about 29°C and drops to 23°C overnight. The warmest of the three months is June, the coolest August.
How summer really feels in Sơn La
Once humidity and wind are folded in, summer brings about 92 days that feel above 32°C and 0 that feel at or below 0°C.
The story in summer is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
Sơn La weather by month
How the three summer months (June, July and August) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 21° / 12° | 24 | 4 | 10.8 | 7.3 |
| Feb | 23° / 13° | 19 | 3.6 | 11.3 | 7.9 |
| Mar | 27° / 16° | 50 | 7.1 | 11.8 | 7.1 |
| Apr | 29° / 19° | 72 | 12.8 | 12.5 | 5.2 |
| May | 30° / 22° | 147 | 19.3 | 13 | 3.7 |
| Jun | 30° / 23° | 209 | 23 | 13.3 | 3.2 |
| Jul | 29° / 23° | 288 | 24.5 | 13.2 | 3.4 |
| Aug | 29° / 22° | 283 | 25.3 | 12.7 | 3.4 |
| Sep | 29° / 21° | 150 | 17.5 | 12.1 | 4.4 |
| Oct | 27° / 19° | 49 | 8.3 | 11.5 | 6.6 |
| Nov | 25° / 16° | 27 | 4.5 | 11 | 7.8 |
| Dec | 22° / 12° | 23 | 3.6 | 10.7 | 7.6 |
Cloud cover in Summer
The sky is clear or mostly clear about 5% of the time across summer.
Chance of precipitation in Summer
Sơn La gets around 780 mm of rain over 73 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 4 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 13 h 12 min in early June to 12 h 24 min by late August. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 4.5 kWh/m².
Hazard calendar for Sơn La
In summer, Sơn La overlaps its monsoon season. The full year is below, with each hazard's peak months called out.
Sơn La's monsoon runs May–September, when most of the year's rain falls.
Is summer a good time to visit Sơn La?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is a weaker month for outdoor sightseeing in Sơn La.
What to pack for Sơn La in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Sơn La sees daytime highs around 29°C and nights near 23°C. Pack light clothes and rain gear. Worth having: sun protection. About 73 days see rain.
UV index in Sơn La in Summer
Clear-sky midday UV across summer averages around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Sơn La peaks around June 20 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 6 (high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 7 | 9 | 11 | 9 | 11 | 14 | 13 | 13 | 9 | 9 | 8 | 6 |
| Level | Very high | Very high | Extreme | Very high | Extreme | Extreme | Extreme | Extreme | Very high | Very high | Very high | High |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 7 | Very high |
| Feb | 9 | Very high |
| Mar | 11 | Extreme |
| Apr | 9 | Very high |
| May | 11 | Extreme |
| Jun | 14 | Extreme |
| Jul | 13 | Extreme |
| Aug | 13 | Extreme |
| Sep | 9 | Very high |
| Oct | 9 | Very high |
| Nov | 8 | Very high |
| Dec | 6 | High |
Air quality in Sơn La in Summer
Average fine-particle pollution (PM2.5) through the year — so you can see where summer falls, not just the annual average.
Air quality in Sơn La is worst in April — around 151 µg/m³ PM2.5 (very unhealthy), about 12.9× the cleanest month (August, 12 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 32 | 38 | 67 | 151 | 58 | 14 | 12 | 12 | 16 | 23 | 26 | 31 |
| Level | Moderate | Poor | Unhealthy | Very unhealthy | Unhealthy | Moderate | Good | Good | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 32 | Moderate |
| Feb | 38 | Poor |
| Mar | 67 | Unhealthy |
| Apr | 151 | Very unhealthy |
| May | 58 | Unhealthy |
| Jun | 14 | Moderate |
| Jul | 12 | Good |
| Aug | 12 | Good |
| Sep | 16 | Moderate |
| Oct | 23 | Moderate |
| Nov | 26 | Moderate |
| Dec | 31 | Moderate |
Where is Sơn La?
Sơn La sits at 21.3°N, 103.9°E, 608 m above sea level, in Vietnam. The nearest listed city is Ít Ong, 24 km away.
Topography around Sơn La
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Sơn La.
Within 3 km, the terrain around Sơn La has significant variations in elevation — a maximum elevation change of 348 m around an average of 674 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,404 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,830 m.
The land around Sơn La is covered by trees (59%) within 3 km, trees (69%) and grassland (21%) within 16 km, and trees (68%) and grassland (27%) within 80 km.
Vietnam travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B / C / F
- 220 V · 50 Hz
- Prices
- ≈ 29% of US
- price level, 2025
- GDP per capita
- $5,066
- 2025
- Happiness
- 6.4 / 10
- World Happiness, 2025
- Safe drinking water
- 59%
- of population, 2024
- Homicide rate
- 1.5
- per 100k, 2011
- Road deaths
- 30.6
- per 100k/yr, 2019
- Income group
- Upper middle
- World Bank
- English
- Moderate
- EF EPI 500
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sơn La (21.3256°, 103.9188°, elevation 608 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.