Nga Sơn weather in September

In September, Nga Sơn sees average daytime highs of 30°C and overnight lows near 26°C, with 310 mm of rain across 20.6 wet days and about 12.1 hours of daylight. It is the 5th-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 30°C through the month. The sky is clear or mostly clear about 21% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 24 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Nga Sơn's 5th-clearest and 12th-windiest month. For the whole year in context, see Nga Sơn's year-round climate.

Daytime high
30°
5th warmest
Overnight low
26°
8th coldest
Rainfall
310 mm
20.6 wet days
Daylight
12 h 06 min
5:47 AM – 5:54 PM
Cloud cover
72%
5th clearest
Wind
10 km/h
12th windiest
Solar energy
4.41 kWh/m²
Travel score
3.6
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 30°C through the month.

A typical September day in Nga Sơn reaches about 30°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 27°C and 32°C. Set against its neighbours, September runs about 1°C cooler than August and about 2°C warmer than October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13126
23126
33126
43126
53126
63126
73126
83126
93026
103026
113026
123026
133026
143026
153026
163026
173026
183026
193026
203025
213025
223025
233025
243025
253025
263025
273025
283025
293025
302925

How September really feels in Nga Sơn

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.

Nga Sơn weather by month

How September compares with the rest of the year at a glance. September is the 5th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan20° / 16°326.310.96.5
Feb21° / 17°173.911.36.9
Mar23° / 19°34611.97.1
Apr27° / 23°60712.46.7
May30° / 26°16714.412.94.2
Jun32° / 28°16614.113.23.2
Jul32° / 28°22616.413.13.1
Aug31° / 27°31922.312.73.0
Sep30° / 26°31020.612.13.6
Oct28° / 23°18014.411.55.5
Nov25° / 20°678.411.17.0
Dec22° / 17°315.810.87.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 21% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 12% of September, with mostly cloudy or overcast conditions the remaining 67%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12179
22179
32179
42278
52278
62278
72377
82476
92575
102575
112773
122773
132971
142971
153268
163268
173367
183565
193664
203862
213961
224060
234159
244258
254456
264456
274555
284654
294654
304852

Chance of precipitation in September

Any precipitation

Nga Sơn gets around 310 mm of rain over 20.6 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 69% and peaks near 79% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
179
279
379
479
579
678
778
877
976
1075
1174
1273
1372
1470
1569
1668
1767
1866
1965
2064
2163
2262
2361
2460
2559
2659
2758
2858
2957
3057

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 76% of days. Sticky, muggy-or-worse air turns up on roughly 99% of them.

0%25%50%75%100%151015202530
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
100496
200595
300694
401693
501792
601891
711989
812988
9121087
10121186
11131284
12131383
13131482
14141580
15141778
16151876
17151975
18162172
19162271
20172369
21172567
22172666
23182764
24182962
25293059
262103157
272103157
282113255
293123352
303133351

Wind in September

Winds average 10 km/h in September, the calmest month.

Across September, daily wind ranges from about 9 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 24 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 36 minutes over September. Sunrise moves from 5:44 AM to 5:50 AM, and sunset from 6:08 PM to 5:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:446:08
212.45:446:07
312.45:446:06
412.35:446:05
512.35:456:04
612.35:456:03
712.35:456:02
812.35:456:01
912.25:466:00
1012.25:466:00
1112.25:465:59
1212.25:465:58
1312.25:465:57
1412.25:475:56
1512.15:475:55
1612.15:475:54
1712.15:475:53
1812.15:475:52
1912.15:485:51
2012.05:485:50
2112.05:485:49
2212.05:485:48
2312.05:495:47
2412.05:495:46
2511.95:495:45
2611.95:495:44
2711.95:505:43
2811.95:505:42
2911.95:505:42
3011.85:505:41

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.41 kWh/m².

For context, solar energy here swings from a low near 2.53 kWh/m² to a high of 5.46 kWh/m² in June across the year — September's 4.41 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.5Bright
44.5Bright
54.4Bright
64.4Bright
74.4Bright
84.4Bright
94.4Bright
104.4Bright
114.4Bright
124.4Bright
134.4Bright
144.4Bright
154.4Bright
164.4Bright
174.4Bright
184.4Bright
194.4Bright
204.4Bright
214.4Bright
224.4Bright
234.4Bright
244.4Bright
254.4Bright
264.4Bright
274.4Bright
284.4Bright
294.4Bright
304.4Bright
Planning a trip in September

Hazard calendar for Nga Sơn

In seasonPeak

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

Nga Sơn sits in the Pacific typhoon belt; the season peaks July–October.

Nga Sơn's monsoon runs May–October, when most of the year's rain falls.

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

Is September a good time to visit Nga Sơn?

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

3.6
Sightseeing
9th-best month of the year
5.0
Beach & pool
8th-best month of the year

September is a weaker month for outdoor sightseeing in Nga Sơn.

What to pack for Nga Sơn in September

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

In September, Nga Sơn sees daytime highs around 30°C and nights near 26°C. Pack light clothes and rain gear. About 21 days see rain.

light clothesrain gear

Sea temperature near Nga Sơn 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 August at about 30°C and coldest in February near 20°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
Jan21Refreshing
Feb20Refreshing
Mar21Refreshing
Apr24Refreshing
May28Warm
Jun29Tropical
Jul30Tropical
Aug30Tropical
Sep29Tropical
Oct28Warm
Nov26Warm
Dec23Refreshing

UV index in Nga Sơn 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 Nga Sơn peaks around July 14 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highHighJul 14UV 12Dec 15UV 6
UV index (midday)Level
Jan7Very high
Feb9Very high
Mar10Very high
Apr8Very high
May10Very high
Jun12Extreme
Jul12Extreme
Aug11Extreme
Sep9Very high
Oct9Very high
Nov7High
Dec6High

Air quality in Nga Sơn 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 Nga Sơn is worst in December — around 134 µg/m³ PM2.5 (unhealthy), about 3.8× the cleanest month (July, 35 µg/m³).

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

0306090120150JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorUnhealthyDec 20132 µg/m³Jul 1536 µg/m³
PM2.5 (µg/m³)Level
Jan126Unhealthy
Feb106Unhealthy
Mar94Unhealthy
Apr87Unhealthy
May60Unhealthy
Jun42Poor
Jul35Moderate
Aug46Poor
Sep69Unhealthy
Oct93Unhealthy
Nov116Unhealthy
Dec134Unhealthy
Location & terrain

Where is Nga Sơn?

Nga Sơn sits at 20.0°N, 106.0°E, 8 m above sea level, in Vietnam. The nearest listed city is Bỉm Sơn, 14 km away.

Topography around Nga Sơn

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

Within 3 km, the terrain around Nga Sơn has only modest variations in elevation — a maximum elevation change of 30 m around an average of 4 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 253 m; within 80 km, large variations in elevation — a maximum elevation change of 989 m.

The land around Nga Sơn is covered by cropland (50%) and artificial surfaces (20%) within 3 km, cropland (37%), trees (23%) and water (20%) within 16 km, and trees (35%), cropland (29%) and water (28%) within 80 km.

3 km
30 m
16 km
253 m
80 km
989 m
treesgrasslandcroplandartificial surfacesbare terrainwatermangroves
September weather nearby: Bỉm Sơn 14 km · Ninh Binh 28 km · Sầm Sơn 31 km · Thanh Hóa 31 km · Nam Định 52 km · Thị Trấn Lam Sơn 60 km · Phủ Lý 60 km · Thái Bình 63 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 Nga Sơn (20.0072°, 105.9704°, elevation 8 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).