Climate and average weather in Ít Ong

In Ít Ong, the summers are humid, hot, wet, and mostly cloudy and the winters are mild and mostly clear.

Best: mid October to mid April

Over the course of the year, the temperature in Ít Ong typically varies from 12°C to 29°C, and is rarely below 7°C or above 33°C. May is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Ít Ong for warm-weather activities is from mid October to mid April.

Hottest
May
29°
Coldest
Jan
12°
Wettest
Aug
428 mm
Driest
Feb
16 mm
Rain / yr
1626 mm
150 wet days
Daylight
10.7–13.3 h
shortest–longest
Elevation
206 m
21.5°N
Clearest
Mar
42% cloud

Ít Ong 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 mid October to mid April.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 6.2 months, from April 3 to October 8, with daily high temperatures above 27°C. The hottest month of the year in Ít Ong is May, with an average high of 29°C and low of 21°C.

The cool season lasts 2.2 months, from December 4 to February 9, with daily high temperatures below 22°C. The coldest month of the year in Ít Ong is January, with an average low of 12°C and high of 20°C.

Days typically run about 8°C warmer than nights, with the widest day–night swing (around 10°C) in March.

10°15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2012
Feb2313
Mar2616
Apr2819
May2921
Jun2822
Jul2822
Aug2822
Sep2821
Oct2619
Nov2416
Dec2112

Average hourly temperature in Ít Ong

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 May afternoons, near 29°C, and coldest before dawn in January, near 12°C.

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

Ít Ong 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
Jan20° / 12°263.810.87.4
Feb23° / 13°163.211.38.1
Mar26° / 16°26511.87.8
Apr28° / 19°35812.56.3
May29° / 21°10916.5134.5
Jun28° / 22°24423.813.33.6
Jul28° / 22°39725.613.23.8
Aug28° / 22°42826.212.73.7
Sep28° / 21°23520.812.14.5
Oct26° / 19°619.411.56.7
Nov24° / 16°283.7118.1
Dec21° / 12°233.510.77.7

Chance of rain

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

Ít Ong gets about 1626 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.1 months, from around May 7 to Oct 7, peaking in August at about 87% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Dec 21.

August is the wettest month by volume, with 428 mm over about 26 wet days; February is the driest, with 16 mm.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetAug 9 · 87%Dec 21 · 8%
Rain on a day (%)Rain days
Jan124
Feb113
Mar165
Apr278
May5317
Jun7924
Jul8326
Aug8426
Sep6821
Oct319
Nov134
Dec114

Monthly rainfall

Over a full year, Ít Ong collects about 1626 mm of rain across 150 wet days — roughly 136 mm in an average month.

It doesn’t fall evenly. August is the wettest month with 428 mm, while February is the driest at just 16 mm. The three wettest months alone bring about 66% of the year’s total.

050100150200250300350400450500JanFebMarAprMayJunJulAugSepOctNovDec26162635109244397428235612823
Rainfall (mm)Rain days
Jan264
Feb163
Mar265
Apr358
May10917
Jun24424
Jul39726
Aug42826
Sep23521
Oct619
Nov284
Dec234

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Ít Ong, 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 October 2 and lasts for 7.3 months, ending around May 10. The clearest month is March, when the sky is clear, mostly clear, or partly cloudy 70% of the time on average.

The cloudier part of the year begins around May 11 and lasts for 4.7 months, ending around October 1. The cloudiest month is June, when it is overcast or mostly cloudy 92% 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%JanFebMarAprMayJunJulAugSepOctNovDecMar 4 · 74%Jun 21 · 6%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan5941
Feb6733
Mar7030
Apr6238
May3466
Jun892
Jul892
Aug1387
Sep2971
Oct5248
Nov6337
Dec6238

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 6, brings about 13 h 18 min of light; the shortest, around January 1, only 10 h 42 min — a swing of roughly 2 h 36 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.86:495:38
Feb11.36:415:56
Mar11.86:186:09
Apr12.55:496:19
May13.05:296:31
Jun13.35:256:43
Jul13.25:346:45
Aug12.75:466:30
Sep12.15:556:02
Oct11.56:045:34
Nov11.06:215:18
Dec10.76:395:21

Sunny days

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

Ít Ong averages about 9 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 18 days.

The sunnier stretch runs 6.5 months, from around Oct 21 to May 6. The sunniest month is March, with roughly 17 sunny days (bright).

The greyest month is June, down near 1 sunny days — about 94% fewer than the March peak.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantMar 618 daysJun 221 days
Sunny daysSky
Jan13Mixed
Feb15Bright
Mar17Bright
Apr13Mixed
May6Gloomy
Jun1Gloomy
Jul1Gloomy
Aug1Gloomy
Sep4Gloomy
Oct9Mixed
Nov14Mixed
Dec14Mixed

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 Ít Ong, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 7.1 months, from around March 30 to October 31. 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 1 to March 29, and January is the most comfortable month — the air is dry or comfortable 98% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJan 23 · 98%Jun 5 · 0%comfortablehumidoppressivemuggydrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
Jan7226200
Feb5834700
Mar23363730
Apr31447351
May03146518
Jun0012475
Jul0001486
Aug0001585
Sep0174647
Oct41030515
Nov253529120
Dec6232610

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

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmFeb 23 · 6 km/hAug 28 · 3 km/h
Wind speed (km/h)Feels
Jan5calm
Feb6calm
Mar6calm
Apr5calm
May4calm
Jun4calm
Jul3calm
Aug3calm
Sep3calm
Oct4calm
Nov4calm
Dec5calm

Hazard calendar for Ít Ong

In seasonPeak

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

Ít Ong's monsoon runs June–September, when most of the year's rain falls.

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

Best time to visit Ít Ong

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around late October, Ít Ong is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

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 time of year to visit Ít Ong for general outdoor tourist activities is from mid October to mid April, with a peak score in the first week of March.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMar 1 · 8.4

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
Jan7.5good
Feb8.1ideal
Mar7.8ideal
Apr6.3good
May4.5fair
Jun3.6fair
Jul3.8fair
Aug3.7fair
Sep4.5fair
Oct6.7good
Nov8.0ideal
Dec7.7ideal

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best times of year to visit Ít Ong for hot-weather activities run from mid February to mid May and again from early October to late November, with a peak score in the second week of March.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationMar 11 · 7.5

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 Ít Ong, 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 May (highs near 29°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 20°C), pack a light layer.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In May, Ít Ong sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 17 days see rain.

UV index (midday) in Ít Ong 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 Ít Ong peaks around June 20 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeExtremeVery highHighJun 20UV 14Dec 19UV 6
UV index (midday)Level
Jan7High
Feb9Very high
Mar12Extreme
Apr10Very high
May11Extreme
Jun14Extreme
Jul13Extreme
Aug13Extreme
Sep9Very high
Oct9Very high
Nov8Very high
Dec6High

Average hourly UV index in Ít Ong

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)
Jan63
Feb74.5
Mar7.55.5
Apr7.55
May8.56
Jun97
Jul8.56.5
Aug86
Sep7.55
Oct74.5
Nov63.5
Dec5.52

Air quality in Ít Ong 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 Ít Ong is worst in April — around 70 µg/m³ PM2.5 (unhealthy), about 4.5× the cleanest month (July, 16 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecPoorUnhealthyModeratePoorApr 1169 µg/m³Jul 2016 µg/m³
PM2.5 (µg/m³)Level
Jan43Poor
Feb48Poor
Mar64Unhealthy
Apr70Unhealthy
May34Moderate
Jun18Moderate
Jul16Moderate
Aug17Moderate
Sep23Moderate
Oct30Moderate
Nov37Poor
Dec42Poor
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Ít Ong 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. Ít Ong banks about 4,342 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)
Jan190
Feb221
Mar343
Apr410
May473
Jun459
Jul462
Aug460
Sep431
Oct390
Nov295
Dec208

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.

Ít Ong receives about 4.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.0 and 5.3 kWh/m².

The brighter stretch of the year lasts 7.3 months, from around Feb 26 to Oct 4. The brightest month is April, averaging about 5.2 kWh/m² (bright).

The dimmest month is January, down near 3.1 kWh/m² — roughly 40% less than the April peak.

0123456JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightApr 265.3 kWhJan 123.0 kWh
Solar energy (kWh/m²)Level
Jan3.0Moderate
Feb3.8Moderate
Mar4.7Bright
Apr5.2Bright
May5.0Bright
Jun4.5Bright
Jul4.3Bright
Aug4.4Bright
Sep4.3Bright
Oct3.9Moderate
Nov3.5Moderate
Dec3.1Moderate

Where is Ít Ong?

Ít Ong sits at 21.5°N, 104.0°E, 206 m above sea level, in Vietnam. The nearest listed city is Sơn La, 24 km away.

SapaYên BáiDien Bien PhuMường Lay

Topography around Ít Ong

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

Within 3 km, the terrain around Ít Ong has large variations in elevation — a maximum elevation change of 913 m around an average of 362 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,314 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,884 m.

The land around Ít Ong is covered by trees (52%) and grassland (33%) within 3 km, trees (64%) and grassland (27%) within 16 km, and trees (72%) and grassland (23%) within 80 km.

3 km
913 m
16 km
2,314 m
80 km
2,884 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Sơn La 24 km · Thị Trấn Thuận Châu 36 km · Nghĩa Lộ 51 km · Thị Trấn Phố Lu 91 km · Sapa 93 km · Yên Bái 94 km · Dien Bien Phu 105 km · Mường Lay 107 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 Ít Ong (21.5175°, 104.027°, elevation 206 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).