Sơn La weather in April

In April, Sơn La sees average daytime highs of 29°C and overnight lows near 19°C, with 72 mm of rain across 12.8 wet days and about 12.5 hours of daylight. It is the 5th-warmest and 6th-wettest month of the year here.

Highs climb over the month, from about 28°C in the first days to 30°C by the end. The sky is clear or mostly clear about 35% of the time in April, and the air most often feels muggy.

Daylight stretches from about 12 h 12 min at the start of April to 12 h 48 min by month's end. Set against the rest of the year, April is Sơn La's 5th-clearest and 5th-windiest month. For the whole year in context, see Sơn La's year-round climate.

Daytime high
29°
5th warmest
Overnight low
19°
7th coldest
Rainfall
72 mm
12.8 wet days
Daylight
12 h 30 min
5:50 AM – 6:19 PM
Cloud cover
55%
5th clearest
Wind
5 km/h
5th windiest
Solar energy
5.26 kWh/m²
Travel score
5.2
out of 10

Sơn La is the old provincial capital of Son La province, Vietnam.

Density
328/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 28°C in the first days to 30°C by the end.

A typical April day in Sơn La reaches about 29°C in the afternoon and slips back to 19°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 33°C. Set against its neighbours, April runs about 2°C warmer than March and about 1°C cooler than May.

10°15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12818
22818
32818
42818
52818
62818
72818
82819
92919
102919
112919
122919
132919
142919
152919
162919
172920
182920
193020
203020
213020
223020
233020
243020
253020
263020
273020
283021
293021
303021

How April really feels in Sơn La

Once humidity and wind are folded in, April averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

April sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Sơn La weather by month

How April compares with the rest of the year at a glance. April is the 5th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan21° / 12°24410.87.3
Feb23° / 13°193.611.37.9
Mar27° / 16°507.111.87.1
Apr29° / 19°7212.812.55.2
May30° / 22°14719.3133.7
Jun30° / 23°2092313.33.2
Jul29° / 23°28824.513.23.4
Aug29° / 22°28325.312.73.4
Sep29° / 21°15017.512.14.4
Oct27° / 19°498.311.56.6
Nov25° / 16°274.5117.8
Dec22° / 12°233.610.77.6

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 35% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 21% of April, with mostly cloudy or overcast conditions the remaining 44%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15545
25545
35644
45743
55644
65743
75743
85842
95842
105842
115842
125842
135842
145842
155842
165842
175743
185743
195743
205644
215545
225545
235545
245545
255446
265446
275347
285248
295149
305149

Chance of precipitation in April

Any precipitation

Sơn La gets around 72 mm of rain over 12.8 wet days in April. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 42% and peaks near 52% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
136
236
337
437
537
638
738
838
939
1039
1139
1240
1340
1440
1541
1642
1742
1843
1944
2044
2145
2246
2346
2447
2548
2648
2749
2850
2951
3052

Humidity in April

DryComfortableHumidMuggyOppressiveMiserable

Most of April feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, April lands in the muggy band about 51% of days. Sticky, muggy-or-worse air turns up on roughly 60% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
171640352
261640362
351639382
451538393
541537403
641536414
731535424
831534435
931434445
1021433456
1121332467
1221331477
1321231488
1411130498
1511129509
1611028529
1719275310
1819255510
1918245611
2018235711
2117225911
2217215912
2306206212
2406196213
2506196213
2605186314
2705176315
2805176315
2905176216
3004166317

Wind in April

Winds average 5 km/h in April.

Across April, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 12 min at the start of April to 12 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 36 minutes over April. Sunrise moves from 6:03 AM to 5:39 AM, and sunset from 6:14 PM to 6:24 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.26:036:14
212.26:036:15
312.26:026:15
412.26:016:15
512.36:006:16
612.35:596:16
712.35:586:16
812.35:576:17
912.35:566:17
1012.45:556:17
1112.45:546:18
1212.45:536:18
1312.45:526:18
1412.45:526:19
1512.55:516:19
1612.55:506:19
1712.55:496:20
1812.55:486:20
1912.55:476:20
2012.65:476:21
2112.65:466:21
2212.65:456:21
2312.65:446:22
2412.65:436:22
2512.75:436:22
2612.75:426:23
2712.75:416:23
2812.75:406:24
2912.75:406:24
3012.85:396:24

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 5.26 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 3.14 kWh/m² to a high of 5.26 kWh/m² in April across the year — April's 5.26 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.1Bright
75.1Bright
85.1Bright
95.2Bright
105.2Bright
115.2Bright
125.2Bright
135.3Bright
145.3Bright
155.3Bright
165.3Bright
175.3Bright
185.4Bright
195.4Bright
205.4Bright
215.4Bright
225.4Bright
235.4Bright
245.4Bright
255.4Bright
265.4Bright
275.4Bright
285.4Bright
295.4Bright
305.4Bright
Planning a trip in April

Hazard calendar for Sơn La

In seasonPeak

None of Sơn La's seasonal hazards are active in April. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Sơn La's monsoon runs May–September, when most of the year's rain falls.

Monsoon
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is April a good time to visit Sơn La?

Our two travel scores rate April for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.2
Sightseeing
7th-best month of the year
6.5
Beach & pool
4th-best month of the year

April is a reasonable time to visit Sơn La for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Sơn La in April

From April's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In April, Sơn La sees daytime highs around 29°C and nights near 19°C. Pack light clothes. Worth having: rain gear and sun protection. About 13 days see rain.

light clothesrain gearsun protection

UV index in Sơn La in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 9 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highExtremeVery highHighJun 20UV 13Dec 18UV 6
UV index (midday)Level
Jan7Very high
Feb9Very high
Mar11Extreme
Apr9Very high
May11Extreme
Jun14Extreme
Jul13Extreme
Aug13Extreme
Sep9Very high
Oct9Very high
Nov8Very high
Dec6High

Air quality in Sơn La in April

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where April 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).

0306090120150JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorUnhealthyModerateGoodModerateApr 16140 µg/m³Aug 912 µg/m³
PM2.5 (µg/m³)Level
Jan32Moderate
Feb38Poor
Mar67Unhealthy
Apr151Very unhealthy
May58Unhealthy
Jun14Moderate
Jul12Good
Aug12Good
Sep16Moderate
Oct23Moderate
Nov26Moderate
Dec31Moderate
Location & terrain

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.

Dien Bien PhuXam NuaVieng XaiMường LayYên Bái

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.

3 km
348 m
16 km
1,404 m
80 km
2,830 m
treesgrasslandcroplandartificial surfacesbare terrainwater
April weather nearby: Ít Ong 24 km · Thị Trấn Thuận Châu 27 km · Nghĩa Lộ 69 km · Dien Bien Phu 93 km · Xam Nua 102 km · Vieng Xai 107 km · Mường Lay 111 km · Yên Bái 112 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
none 86%Catholic 6%Buddhist 6%Protestant 1%

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. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).