Duyên Hải weather in September

In September, Duyên Hải sees average daytime highs of 29°C and overnight lows near 26°C, with 225 mm of rain across 27.8 wet days and about 12.1 hours of daylight. It is the 6th-warmest and 2nd-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 4% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 12 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Duyên Hải's 12th-clearest and 9th-windiest month. For the whole year in context, see Duyên Hải's year-round climate.

Daytime high
29°
6th warmest
Overnight low
26°
6th coldest
Rainfall
225 mm
27.8 wet days
Daylight
12 h 06 min
5:47 AM – 5:50 PM
Cloud cover
85%
12th clearest
Wind
14 km/h
9th windiest
Solar energy
4.95 kWh/m²
Travel score
2.9
out of 10

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 Duyên Hải reaches about 29°C in the afternoon and slips back to 26°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 31°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)
13026
23026
33026
43026
52926
62926
72926
82926
92926
102926
112926
122926
132926
142926
152926
162926
172926
182926
192926
202926
212926
222926
232926
242926
252926
262926
272926
282926
292926
302926

How September really feels in Duyên Hải

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.

Duyên Hải weather by month

How September compares with the rest of the year at a glance. September is the 6th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan27° / 25°232.811.57.4
Feb27° / 25°6111.77.8
Mar29° / 26°213.511.96.6
Apr30° / 27°5810.412.25.0
May31° / 27°17024.212.43.1
Jun30° / 26°20727.112.62.8
Jul30° / 26°19728.712.52.9
Aug30° / 26°19528.812.32.9
Sep29° / 26°22527.812.12.9
Oct29° / 26°27627.411.83.3
Nov29° / 26°16016.611.64.7
Dec28° / 25°869.211.46.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 4% of the time in September, the cloudiest month of the year.

Beyond those clear spells, partly cloudy skies cover about 8% of September, with mostly cloudy or overcast conditions the remaining 88%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
11288
21288
31288
41288
51288
61288
71288
81288
91288
101288
111288
121288
131288
141288
151288
161288
171288
181288
191288
201288
211288
221288
231288
241387
251387
261387
271387
281387
291387
301387

Chance of precipitation in September

Any precipitation

Duyên Hải gets around 225 mm of rain over 27.8 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 93% and peaks near 94% on the wettest days.

0%20%40%60%80%100%151015202530
Rain chance (%)
192
292
392
492
592
692
793
893
993
1094
1194
1294
1394
1494
1594
1694
1794
1894
1993
2093
2193
2293
2393
2492
2592
2692
2793
2893
2993
3093

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 91% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
1991
2991
3991
4991
5991
6991
7991
8991
9991
10991
11991
12991
13991
14991
15991
16991
17892
18892
19892
20892
21892
22892
23892
24892
25892
26892
27991
28991
29991
30991

Wind in September

Winds average 14 km/h in September.

Across September, daily wind ranges from about 12 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
115light breeze
215light breeze
315light breeze
415light breeze
515light breeze
615light breeze
715light breeze
815light breeze
915light breeze
1015light breeze
1115light breeze
1215light breeze
1315light breeze
1415light breeze
1515light breeze
1615light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2912light breeze
3012light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 12 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 18 minutes over September. Sunrise moves from 5:48 AM to 5:46 AM, and sunset from 5:59 PM to 5:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.25:485:59
212.25:485:59
312.25:485:58
412.25:485:58
512.25:485:57
612.15:485:56
712.15:485:56
812.15:485:55
912.15:475:54
1012.15:475:54
1112.15:475:53
1212.15:475:53
1312.15:475:52
1412.15:475:51
1512.15:475:51
1612.15:475:50
1712.05:475:49
1812.05:475:49
1912.05:465:48
2012.05:465:47
2112.05:465:47
2212.05:465:46
2312.05:465:45
2412.05:465:45
2512.05:465:44
2612.05:465:44
2712.05:465:43
2811.95:465:42
2911.95:465:42
3011.95:465:41

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.95 kWh/m².

For context, solar energy here swings from a low near 4.65 kWh/m² to a high of 6.44 kWh/m² in April across the year — September's 4.95 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.2Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.1Bright
75.1Bright
85.1Bright
95.0Bright
105.0Bright
115.0Bright
125.0Bright
134.9Bright
144.9Bright
154.9Bright
164.9Bright
174.9Bright
184.8Bright
194.8Bright
204.8Bright
214.8Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.8Bright
Planning a trip in September

Hazard calendar for Duyên Hải

In seasonPeak

In September, Duyên Hải sits inside its pacific typhoon and rainy season season. The full year is below, with each hazard's peak months called out.

Duyên Hải sits in the Pacific typhoon belt; the season peaks July–October.

Duyên Hải's rainy season runs May–November, when most of the year's rain falls.

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

Is September a good time to visit Duyên Hải?

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

2.9
Sightseeing
9th-best month of the year
3.9
Beach & pool
12th-best month of the year

September is a weaker month for outdoor sightseeing in Duyên Hải.

What to pack for Duyên Hải in September

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

In September, Duyên Hải sees daytime highs around 29°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 28 days see rain.

light clothesrain gearsun protection

Sea temperature near Duyên Hải 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 15 km away) is warmest in May at about 30°C and coldest in January near 26°C.

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

24°26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan26Warm
Feb26Warm
Mar27Warm
Apr29Tropical
May30Tropical
Jun30Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov28Tropical
Dec27Warm

UV index in Duyên Hải in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Duyên Hải peaks around March 24 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 10 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highMar 24UV 13Dec 10UV 10
UV index (midday)Level
Jan11Extreme
Feb12Extreme
Mar13Extreme
Apr13Extreme
May13Extreme
Jun11Extreme
Jul12Extreme
Aug13Extreme
Sep13Extreme
Oct11Extreme
Nov10Very high
Dec10Very high

Air quality in Duyên Hải 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 Duyên Hải is worst in December — around 34 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (March, 19 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateDec 1333 µg/m³Mar 1719 µg/m³
PM2.5 (µg/m³)Level
Jan24Moderate
Feb20Moderate
Mar19Moderate
Apr20Moderate
May22Moderate
Jun24Moderate
Jul25Moderate
Aug23Moderate
Sep28Moderate
Oct33Moderate
Nov30Moderate
Dec34Moderate
Location & terrain

Where is Duyên Hải?

Duyên Hải sits at 9.6°N, 106.5°E, 2 m above sea level, in Vietnam. The nearest listed city is Trà Vinh, 38 km away.

Topography around Duyên Hải

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

Within 3 km, the terrain around Duyên Hải has only modest variations in elevation — a maximum elevation change of 9 m around an average of 3 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 21 m; within 80 km, only modest variations in elevation — a maximum elevation change of 24 m.

The land around Duyên Hải is covered by water (40%) and trees (21%) within 3 km, water (52%) within 16 km, and water (53%), trees (23%) and cropland (20%) within 80 km.

3 km
9 m
16 km
21 m
80 km
24 m
treesgrasslandcroplandartificial surfacesbare terrainwatermangroves
September weather nearby: Trà Vinh 38 km · Sóc Trăng 57 km · Vĩnh Châu 66 km · Bến Tre 69 km · Ngã Bảy 76 km · Mỹ Tho 82 km · Gò Công 84 km · Phú Lộc 86 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 Duyên Hải (9.635°, 106.4924°, elevation 2 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).