Ít Ong in Fall

In fall (September, October and November), Ít Ong sees average daytime highs around 26°C and overnight lows near 18°C, with 323 mm of rain over about 34 wet days across the season. It is the 3rd-warmest season and the 2nd-wettest season.

Over the season highs ease from about 28°C in early September to 23°C by late November. The sky is clear or mostly clear about 29% of the time across fall, and the air most often feels muggy.

Fall is Ít Ong's 2nd-best season to visit on our travel score. For the whole year in context, see Ít Ong's year-round climate.

Avg daytime high
26°C
3rd-warmest season
Avg overnight low
18°C
Rainfall
323 mm
34 wet days
Avg wind
4 km/h
Travel score
6.4
2nd-best season
Months
Sep · Oct · Nov

Temperature in Ít Ong in Fall

Average highAverage lowShaded bands: 10–90% of days

Over the season highs ease from about 28°C in early September to 23°C by late November.

A typical fall day in Ít Ong reaches about 26°C and drops to 18°C overnight. The warmest of the three months is September, the coolest November.

10°15°20°25°30°35°SepOctNov

Ít Ong weather by month

How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.

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

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitation

Ít Ong gets around 323 mm of rain over 34 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%80%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

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

0%25%50%75%100%SepOctNov

Wind in Fall

Winds average 4 km/h across fall.

0246810SepOctNov

Sunrise & sunset in Fall

DaylightNight

Daylight runs from about 12 h 24 min in early September to 10 h 48 min by late November. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMSepOctNov

Solar energy in Fall

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across fall, about 3.9 kWh/m².

012345SepOctNov
Planning a trip in fall

Hazard calendar for Ít Ong

In seasonPeak

In fall, Ít Ong overlaps its monsoon season. The full year is below, with each hazard's peak months called out.

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

Is fall a good time to visit Ít Ong?

Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

6.4
Sightseeing
2nd-best month of the year
6.1
Beach & pool
2nd-best month of the year

fall is a reasonable time to visit Ít Ong for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Ít Ong in Fall

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

In fall, Ít Ong sees daytime highs around 26°C and nights near 18°C. Pack light clothes and rain gear. About 34 days see rain.

light clothesrain gear

UV index in Ít Ong in Fall

LowModerateHighVery highExtreme

Clear-sky midday UV across fall averages 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 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

Air quality in Ít Ong in Fall

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual 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
Location & terrain

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
Fall weather 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.