Bo in Fall

In fall (September, October and November), Bo sees average daytime highs around 27°C and overnight lows near 21°C, with 512 mm of rain over about 44 wet days across the season. It is the 3rd-warmest season and the 2nd-wettest season.

Over the season highs ease from about 30°C in early September to 23°C by late November. The sky is clear or mostly clear about 25% of the time across fall, and the air most often feels oppressive.

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

Avg daytime high
27°C
3rd-warmest season
Avg overnight low
21°C
Rainfall
512 mm
44 wet days
Avg wind
6 km/h
Travel score
5.4
2nd-best season
Months
Sep · Oct · Nov

Temperature in Bo in Fall

Average highAverage lowShaded bands: 10–90% of days

Over the season highs ease from about 30°C in early September to 23°C by late November.

A typical fall day in Bo reaches about 27°C and drops to 21°C overnight. The warmest of the three months is September, the coolest November.

10°15°20°25°30°35°SepOctNov

How fall really feels in Bo

Once humidity and wind are folded in, fall brings about 30 days that feel above 32°C and 0 that feel at or below 0°C.

Days feeling ≥ 32°C
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in fall is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Bo 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
Jan19° / 14°448.510.96.0
Feb21° / 15°287.211.36.3
Mar24° / 18°5910.411.96.4
Apr28° / 21°11413.512.55.3
May31° / 24°27520.2133.4
Jun32° / 26°26721.113.22.7
Jul32° / 26°32023.613.12.7
Aug31° / 25°39326.412.72.7
Sep30° / 24°29021.112.13.6
Oct27° / 21°15614.711.55.6
Nov24° / 18°668.2117.0
Dec21° / 14°356.310.86.8

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 25% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitation

Bo gets around 512 mm of rain over 44 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%20%40%60%80%100%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

Most of fall feels oppressive — 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 6 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 3.7 kWh/m².

012345SepOctNov
Planning a trip in fall

Hazard calendar for Bo

In seasonPeak

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

Bo'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 fall a good time to visit Bo?

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.

5.4
Sightseeing
2nd-best month of the year
5.6
Beach & pool
1st-best month of the year

fall is a reasonable time to visit Bo for sightseeing.

What to pack for Bo in Fall

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

In fall, Bo sees daytime highs around 27°C and nights near 21°C. Pack light clothes and rain gear. About 44 days see rain.

light clothesrain gear

UV index in Bo in Fall

LowModerateHighVery highExtreme

Clear-sky midday UV across fall averages around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Bo peaks around June 20 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 22 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highHighExtremeVery highHighJun 20UV 11Nov 22UV 6
UV index (midday)Level
Jan6High
Feb7High
Mar9Very high
Apr6High
May7High
Jun12Extreme
Jul10Extreme
Aug10Extreme
Sep7High
Oct8Very high
Nov6High
Dec6High

Air quality in Bo 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 Bo is worst in December — around 171 µg/m³ PM2.5 (very unhealthy), about 3.4× the cleanest month (July, 50 µg/m³).

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

0306090120150180JanFebMarAprMayJunJulAugSepOctNovDecVery unhealthyUnhealthyPoorUnhealthyVery unhealthyDec 19170 µg/m³Jul 1452 µg/m³
PM2.5 (µg/m³)Level
Jan161Very unhealthy
Feb136Unhealthy
Mar122Unhealthy
Apr106Unhealthy
May76Unhealthy
Jun59Unhealthy
Jul50Poor
Aug68Unhealthy
Sep96Unhealthy
Oct125Unhealthy
Nov152Very unhealthy
Dec171Very unhealthy
Location & terrain

Where is Bo?

Bo sits at 20.7°N, 105.5°E, 67 m above sea level, in Vietnam. The nearest listed city is Xuân Mai, 26 km away.

Topography around Bo

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

Within 3 km, the terrain around Bo has significant variations in elevation — a maximum elevation change of 427 m around an average of 122 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,185 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,622 m.

The land around Bo is covered by trees (71%) and cropland (23%) within 3 km, trees (86%) within 16 km, and trees (60%) and cropland (27%) within 80 km.

3 km
427 m
16 km
1,185 m
80 km
1,622 m
treesgrasslandcroplandartificial surfaceswater
Fall weather nearby: Xuân Mai 26 km · Hòa Bình 26 km · Phủ Lý 42 km · Hà Đông 42 km · Dại Mỗ 42 km · Vinhomes Smart City 43 km · Tây Mỗ 43 km · Thanh Liệt 44 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 Bo (20.6726°, 105.5362°, elevation 67 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.