Chittagong weather in September

In September, Chittagong sees average daytime highs of 29°C and overnight lows near 27°C, with 340 mm of rain across 25.6 wet days and about 12.1 hours of daylight. It is the 5th-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 7% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 30 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Chittagong's 9th-clearest and 5th-windiest month. For the whole year in context, see Chittagong's year-round climate.

Daytime high
29°
5th warmest
Overnight low
27°
9th coldest
Rainfall
340 mm
25.6 wet days
Daylight
12 h 06 min
5:43 AM – 5:51 PM
Cloud cover
83%
9th clearest
Wind
15 km/h
5th windiest
Solar energy
4.27 kWh/m²
Travel score
3.3
out of 10

Chittagong is second largest city of Bangladesh, situated at the southwestern part of the country.

Air quality
Severe
PM2.5 56.4 µg/m³ · 2018
Density
24,351/km²
people per km²

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical September day in Chittagong reaches about 29°C in the afternoon and slips back to 27°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 30°C. Set against its neighbours, September runs on par with August and on par with October.

25°28°30°33°35°151015202530
Avg high (°C)Avg low (°C)
12927
22927
32927
42927
52927
62927
72927
82927
92927
102927
112927
122927
132927
142927
152927
162927
172927
182927
192927
202927
212927
222927
232927
242927
252927
262927
272927
282927
292927
302927

How September really feels in Chittagong

Once humidity and wind are folded in, September averages 30 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
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

Chittagong weather by month

How September compares with the rest of the year at a glance. September is the 5th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan23° / 18°60.810.89.3
Feb25° / 20°141.811.29.0
Mar28° / 24°464.411.87.6
Apr29° / 26°989.412.55.7
May30° / 27°29120.513.14.1
Jun29° / 27°58326.813.33.1
Jul29° / 27°60629.313.23.0
Aug29° / 27°45428.712.83.1
Sep29° / 27°34025.612.13.3
Oct29° / 26°20317.311.54.8
Nov27° / 23°483.910.97.8
Dec25° / 19°121.210.79.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 7% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 9% of September, with mostly cloudy or overcast conditions the remaining 84%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1892
2892
3892
4892
5991
61090
71090
81189
91189
101189
111288
121288
131288
141288
151387
161387
171486
181684
191783
201783
211981
222080
232278
242278
252476
262674
272872
282971
293070
303268

Chance of precipitation in September

Any precipitation

Chittagong gets around 340 mm of rain over 25.6 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 86% and peaks near 91% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%100%151015202530
Rain chance (%)
191
291
390
490
589
689
789
888
988
1087
1187
1287
1387
1486
1586
1686
1786
1886
1985
2085
2184
2283
2383
2482
2582
2681
2781
2880
2979
3079

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the miserable band about 99% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
10100
20100
30100
40100
50100
60100
70100
80100
90100
100100
110100
120100
130100
140100
150100
160100
170100
18199
19199
20199
21199
22199
23199
24298
25298
26298
27298
28298
29397
30397

Wind in September

Winds average 15 km/h in September.

Across September, daily wind ranges from about 11 km/h on the calmest days to 18 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
118light breeze
218light breeze
318light breeze
417light breeze
517light breeze
617light breeze
717light breeze
817light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1315light breeze
1415light breeze
1515light breeze
1615light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2512light breeze
2612light breeze
2712calm
2812calm
2911calm
3011calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 30 min at the start of September to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 42 minutes over September. Sunrise moves from 5:39 AM to 5:47 AM, and sunset from 6:06 PM to 5:37 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.55:396:06
212.45:396:05
312.45:396:04
412.45:406:03
512.45:406:02
612.35:406:01
712.35:416:00
812.35:415:59
912.35:415:58
1012.35:415:57
1112.25:425:56
1212.25:425:55
1312.25:425:54
1412.25:435:53
1512.15:435:52
1612.15:435:51
1712.15:435:50
1812.15:445:49
1912.15:445:48
2012.05:445:47
2112.05:455:46
2212.05:455:45
2312.05:455:44
2412.05:465:43
2511.95:465:42
2611.95:465:41
2711.95:465:40
2811.95:475:39
2911.85:475:38
3011.85:475:37

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.27 kWh/m².

For context, solar energy here swings from a low near 3.87 kWh/m² to a high of 6.16 kWh/m² in April across the year — September's 4.27 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.2Bright
24.2Bright
34.2Bright
44.2Bright
54.2Bright
64.2Bright
74.2Bright
84.2Bright
94.2Bright
104.2Bright
114.2Bright
124.2Bright
134.2Bright
144.2Bright
154.3Bright
164.3Bright
174.3Bright
184.3Bright
194.3Bright
204.3Bright
214.3Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.3Bright
274.3Bright
284.4Bright
294.4Bright
304.4Bright
Planning a trip in September

Hazard calendar for Chittagong

In seasonPeak

In September, Chittagong sits inside its cyclone and monsoon season. The full year is below, with each hazard's peak months called out.

Chittagong sits in the North Indian Ocean cyclone zone; the season peaks May and October–November.

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

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

Is September a good time to visit Chittagong?

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

3.3
Sightseeing
9th-best month of the year
4.3
Beach & pool
9th-best month of the year

September is a weaker month for outdoor sightseeing in Chittagong.

What to pack for Chittagong in September

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

In September, Chittagong sees daytime highs around 29°C and nights near 27°C. Pack light clothes and rain gear. About 26 days see rain.

light clothesrain gear

Sea temperature near Chittagong in September

The nearest coast averages about 29°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 22 km away) is warmest in October at about 29°C and coldest in January near 22°C.

The water stays above 20°C all year — warm enough for a swim any month.

20°25°30°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan22Refreshing
Feb23Refreshing
Mar26Warm
Apr28Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov27Warm
Dec24Refreshing

UV index in Chittagong in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Chittagong peaks around July 21 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near January 10 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highExtremeVery highHighJul 21UV 13Jan 10UV 6
UV index (midday)Level
Jan6High
Feb7High
Mar8Very high
Apr8Very high
May10Extreme
Jun8Very high
Jul13Extreme
Aug11Extreme
Sep9Very high
Oct6High
Nov7High
Dec6High

Air quality in Chittagong in September

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Chittagong is worst in January — around 117 µg/m³ PM2.5 (unhealthy), about 5.3× the cleanest month (July, 22 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Chittagong's WHO annual average of 56.4 µg/m³.

0306090120JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorModeratePoorUnhealthyJan 16114 µg/m³Jul 1723 µg/m³
PM2.5 (µg/m³)Level
Jan117Unhealthy
Feb92Unhealthy
Mar79Unhealthy
Apr49Poor
May34Moderate
Jun27Moderate
Jul22Moderate
Aug26Moderate
Sep26Moderate
Oct43Poor
Nov67Unhealthy
Dec95Unhealthy
Location & terrain

Where is Chittagong?

Chittagong sits at 22.3°N, 91.8°E, 15 m above sea level, in Bangladesh. The nearest listed city is Cox's Bazar, 102 km away.

Cox's BazarBarisalButhidaung TownKyauktawDhakaBagerhatKhulna

Topography around Chittagong

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

Within 3 km, the terrain around Chittagong has only modest variations in elevation — a maximum elevation change of 60 m around an average of 12 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 96 m; within 80 km, large variations in elevation — a maximum elevation change of 893 m.

The land around Chittagong is covered by artificial surfaces (62%) and trees (22%) within 3 km, trees (43%) and water (27%) within 16 km, and trees (53%) and water (33%) within 80 km.

3 km
60 m
16 km
96 m
80 km
893 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Cox's Bazar 102 km · Barisal 156 km · Buthidaung Town 178 km · Hakha 186 km · Kyauktaw 204 km · Dhaka 211 km · Bagerhat 213 km · Khulna 239 km

Bangladesh travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type A / C / D / G
220 V · 50 Hz
Prices
≈ 25% of US
price level, 2025
GDP per capita
$2,597
2025
Happiness
4.3 / 10
World Happiness, 2025
Safe drinking water
59%
of population, 2024
Homicide rate
2.3
per 100k, 2018
Road deaths
15.3
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Moderate
EF EPI 506
Religion
Muslim 91%Hindu 8%other 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 Chittagong (22.3384°, 91.8317°, elevation 15 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).