Climate and average weather in Lào Cai

In Lào Cai, the summers are muggy, hot, wet, and mostly cloudy and the winters are mild and mostly cloudy.

Best: late September to early January

Over the course of the year, the temperature in Lào Cai typically varies from 11°C to 30°C, and is rarely below 7°C or above 34°C. June is the hottest month of the year, while January is the coldest.

Based on the travel score, the best times of year to visit Lào Cai for warm-weather activities are from mid February to late April and late September to early January.

Hottest
Jun
30°
Coldest
Jan
11°
Wettest
Aug
268 mm
Driest
Feb
87 mm
Rain / yr
1871 mm
222 wet days
Daylight
10.6–13.4 h
shortest–longest
Elevation
86 m
22.5°N
Clearest
Nov
60% cloud

Lào Cai weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late September to early January.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Lào Cai, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 5.8 months, from April 12 to October 3, with daily high temperatures above 27°C. The hottest month of the year in Lào Cai is June, with an average high of 30°C and low of 24°C.

The cool season lasts 2.4 months, from December 3 to February 14, with daily high temperatures below 20°C. The coldest month of the year in Lào Cai is January, with an average low of 11°C and high of 18°C.

Days typically run about 7°C warmer than nights year-round.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan1811
Feb2012
Mar2415
Apr2719
May2922
Jun3024
Jul3024
Aug3023
Sep2822
Oct2619
Nov2315
Dec1912

How hot and cold Lào Cai really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Lào Cai feels like about 34°C (around June 17). About 104 days a year carry some heat stress, peaking in June.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan18181111
Feb20201212
Mar24241515
Apr28271919
May32292222
Jun34302424
Jul33302424
Aug33302323
Sep31282222
Oct26261919
Nov22231515
Dec19191212

Average hourly temperature in Lào Cai

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on June afternoons, near 30°C, and coldest before dawn in January, near 11°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Lào Cai weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan18° / 11°9618.110.84.7
Feb20° / 12°871711.25.0
Mar24° / 15°1261911.85.5
Apr27° / 19°12917.612.55.2
May29° / 22°20019.713.14.1
Jun30° / 24°2422213.43.3
Jul30° / 24°26123.213.23.4
Aug30° / 23°26822.412.83.6
Sep28° / 22°16518.212.14.6
Oct26° / 19°11816.611.55.7
Nov23° / 15°8813.810.96.1
Dec19° / 12°9214.110.65.5

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Lào Cai gets about 1871 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 4.4 months, from around May 7 to Sep 16, peaking in July at about 76% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Dec 20.

August is the wettest month by volume, with 268 mm over about 22 wet days; February is the driest, with 87 mm.

0%10%20%30%40%50%60%70%80%90%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetJul 25 · 76%Dec 20 · 43%
Rain on a day (%)Rain days
Jan5818
Feb6017
Mar6219
Apr5918
May6420
Jun7322
Jul7523
Aug7222
Sep6118
Oct5317
Nov4714
Dec4614

Monthly rainfall

Over a full year, Lào Cai collects about 1871 mm of rain across 222 wet days — roughly 156 mm in an average month.

It doesn’t fall evenly. August is the wettest month with 268 mm, while February is the driest at just 87 mm. The three wettest months alone bring about 41% of the year’s total.

050100150200250300JanFebMarAprMayJunJulAugSepOctNovDec96871261292002422612681651188892
Rainfall (mm)Rain days
Jan9618
Feb8717
Mar12619
Apr12918
May20020
Jun24222
Jul26123
Aug26822
Sep16518
Oct11817
Nov8814
Dec9214

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Lào Cai, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around September 13 and lasts for 3.8 months, ending around January 5. The clearest month is April, when the sky is clear, mostly clear, or partly cloudy 46% of the time on average.

The cloudier part of the year begins around May 19 and lasts for 3.8 months, ending around September 12. The cloudiest month is June, when it is overcast or mostly cloudy 90% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecNov 8 · 49%Jun 22 · 8%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearer
Clearer (%)Cloudier (%)
Jan3070
Feb3862
Mar4258
Apr4654
May3466
Jun1090
Jul1387
Aug2278
Sep3565
Oct4159
Nov4555
Dec3862

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 12, brings about 13 h 24 min of light; the shortest, around January 1, only 10 h 36 min — a swing of roughly 2 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.86:515:36
Feb11.26:425:56
Mar11.86:196:09
Apr12.55:496:20
May13.15:286:33
Jun13.45:236:45
Jul13.25:326:47
Aug12.85:456:32
Sep12.15:556:02
Oct11.56:055:33
Nov10.96:225:16
Dec10.66:415:19

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Lào Cai averages about 6 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 9 days.

The sunnier stretch runs 3.5 months, from around Jan 30 to May 15. The sunniest month is April, with roughly 9 sunny days (mixed).

The greyest month is June, down near 1 sunny days — about 88% fewer than the April peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedApr 149 daysJun 211 days
Sunny daysSky
Jan6Gloomy
Feb7Gloomy
Mar8Mixed
Apr9Mixed
May6Gloomy
Jun1Gloomy
Jul2Gloomy
Aug3Gloomy
Sep6Gloomy
Oct6Gloomy
Nov8Mixed
Dec7Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Lào Cai, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 7.3 months, from around March 24 to November 1. The muggiest month is June, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around November 2 to March 23, and January is the most comfortable month — the air is dry or comfortable 95% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJan 19 · 96%Jun 4 · 0%comfortablehumidoppressivemuggydrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan63325000
Feb493515100
Mar1827391600
Apr2103045130
May02838520
Jun0017911
Jul0002972
Aug0007921
Sep02634580
Oct3102449140
Nov1831321910
Dec503811100

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in Lào Cai is steady company: average speeds sit near 4 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmMar 4 · 5 km/hAug 28 · 3 km/h
Wind speed (km/h)Feels
Jan4calm
Feb4calm
Mar5calm
Apr4calm
May4calm
Jun3calm
Jul3calm
Aug3calm
Sep3calm
Oct3calm
Nov4calm
Dec4calm

Hazard calendar for Lào Cai

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Lào Cai's rainy season runs March–September, when most of the year's rain falls.

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

Best time to visit Lào Cai

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Lào Cai throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late December, Lào Cai is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best times of year to visit Lào Cai for general outdoor tourist activities run from mid February to late April and again from late September to early January, with a peak score in the second week of November.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationNov 8 · 6.3

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan4.7fair
Feb5.0fair
Mar5.4fair
Apr5.1fair
May4.1fair
Jun3.3poor
Jul3.4poor
Aug3.6fair
Sep4.6fair
Oct5.7good
Nov6.0good
Dec5.5fair

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Lào Cai for hot-weather activities is from mid March to mid November, with a peak score in the last week of April.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationApr 26 · 5.7

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Lào Cai, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around June (highs near 30°C), the essentials are light clothes and rain gear. In the cold season around January (highs near 18°C), pack rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In June, Lào Cai sees daytime highs around 30°C and nights near 24°C. Pack light clothes and rain gear. About 22 days see rain.

UV index (midday) in Lào Cai by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Lào Cai peaks around June 21 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 18 at about 5 (high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highVery highExtremeVery highHighJun 21UV 13Dec 18UV 5
UV index (midday)Level
Jan6High
Feb8Very high
Mar11Extreme
Apr8Very high
May10Very high
Jun14Extreme
Jul13Extreme
Aug12Extreme
Sep10Very high
Oct8Very high
Nov7High
Dec5High

Average hourly UV index in Lào Cai

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in June the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 7 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan5.52
Feb6.53.5
Mar7.55.5
Apr7.54.5
May85.5
Jun97
Jul8.56.5
Aug86
Sep7.55
Oct6.54
Nov62.5
Dec50

Air quality in Lào Cai by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in Lào Cai is worst in March — around 49 µg/m³ PM2.5 (poor), about 2.8× the cleanest month (July, 17 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorModeratePoorMar 2349 µg/m³Jul 1817 µg/m³
PM2.5 (µg/m³)Level
Jan36Poor
Feb40Poor
Mar49Poor
Apr48Poor
May30Moderate
Jun19Moderate
Jul17Moderate
Aug18Moderate
Sep23Moderate
Oct28Moderate
Nov33Moderate
Dec36Poor
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Lào Cai is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Lào Cai banks about 4,245 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around June.

01,0002,0003,0004,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan134
Feb164
Mar283
Apr387
May479
Jun505
Jul517
Aug508
Sep452
Oct384
Nov267
Dec166

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Lào Cai receives about 3.9 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 2.6 and 5.1 kWh/m².

The brighter stretch of the year lasts 7.1 months, from around Mar 3 to Oct 3. The brightest month is May, averaging about 4.9 kWh/m² (bright).

The dimmest month is January, down near 2.6 kWh/m² — roughly 46% less than the May peak.

0123456JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightMay 15.1 kWhJan 152.6 kWh
Solar energy (kWh/m²)Level
Jan2.6Moderate
Feb3.3Moderate
Mar4.3Bright
Apr4.9Bright
May4.9Bright
Jun4.5Bright
Jul4.3Bright
Aug4.4Bright
Sep4.3Bright
Oct3.5Moderate
Nov3.1Moderate
Dec2.7Moderate

Where is Lào Cai?

Lào Cai sits at 22.5°N, 104.0°E, 86 m above sea level, in Vietnam. The nearest listed city is Sapa, 21 km away.

Bắc QuangMường LayÍt OngHà Giang

Topography around Lào Cai

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Lào Cai.

Within 3 km, the terrain around Lào Cai has significant variations in elevation — a maximum elevation change of 298 m around an average of 141 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,148 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,050 m.

The land around Lào Cai is covered by trees (65%) and artificial surfaces (26%) within 3 km, trees (90%) within 16 km, and trees (85%) within 80 km.

3 km
298 m
16 km
2,148 m
80 km
3,050 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Sapa 21 km · Thị Trấn Phố Lu 29 km · Lai Châu 54 km · Thị Trấn Việt Quang 86 km · Bắc Quang 92 km · Mường Lay 102 km · Ít Ong 108 km · Hà Giang 111 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 Lào Cai (22.4856°, 103.9707°, elevation 86 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).