Climate and average weather in Nga Sơn

In Nga Sơn, the summers are oppressive, hot, showery, and mostly cloudy and the winters are mild and mostly cloudy.

Best: late October to late April

Over the course of the year, the temperature in Nga Sơn typically varies from 16°C to 32°C, and is rarely below 11°C or above 35°C. June is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Nga Sơn for warm-weather activities is from late October to late April.

Hottest
Jun
32°
Coldest
Jan
16°
Wettest
Aug
319 mm
Driest
Feb
17 mm
Rain / yr
1607 mm
140 wet days
Daylight
10.8–13.2 h
shortest–longest
Elevation
8 m
20.0°N
Clearest
Nov
56% cloud

Nga Sơn weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around late October to late April.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Nga Sơn, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 4.9 months, from May 6 to October 2, with daily high temperatures above 29°C. The hottest month of the year in Nga Sơn is June, with an average high of 32°C and low of 28°C.

The cool season lasts 2.9 months, from December 8 to March 6, with daily high temperatures below 22°C. The coldest month of the year in Nga Sơn is January, with an average low of 16°C and high of 20°C.

Days typically run about 4°C warmer than nights year-round.

10°15°20°25°30°35°40°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2016
Feb2117
Mar2319
Apr2723
May3026
Jun3228
Jul3228
Aug3127
Sep3026
Oct2823
Nov2520
Dec2217

How hot and cold Nga Sơn really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Nga Sơn feels like about 41°C (around June 22). About 165 days a year carry some heat stress, and 90 of them tip into dangerous heat (feels-like above 39°C), peaking in June.

15°20°25°30°35°40°45°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan20201616
Feb21211717
Mar23231919
Apr28272323
May36302626
Jun41322828
Jul41322828
Aug40312727
Sep36302626
Oct31282323
Nov25252020
Dec22221717

Average hourly temperature in Nga Sơn

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on June afternoons, near 32°C, and coldest before dawn in January, near 16°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Nga Sơn weather by month

Every month at a glance. Click a month for its detailed page.

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

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Nga Sơn gets about 1607 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.7 months, from around May 6 to Oct 25, peaking in September at about 78% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Feb 11.

August is the wettest month by volume, with 319 mm over about 22 wet days; February is the driest, with 17 mm.

0%10%20%30%40%50%60%70%80%90%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetSep 1 · 78%Feb 11 · 14%
Rain on a day (%)Rain days
Jan196
Feb144
Mar196
Apr257
May4614
Jun4714
Jul5316
Aug7122
Sep6921
Oct4614
Nov298
Dec196

Monthly rainfall

Over a full year, Nga Sơn collects about 1607 mm of rain across 140 wet days — roughly 134 mm in an average month.

It doesn’t fall evenly. August is the wettest month with 319 mm, while February is the driest at just 17 mm. The three wettest months alone bring about 53% of the year’s total.

050100150200250300350JanFebMarAprMayJunJulAugSepOctNovDec321734601671662263193101806731
Rainfall (mm)Rain days
Jan326
Feb174
Mar346
Apr607
May16714
Jun16614
Jul22616
Aug31922
Sep31021
Oct18014
Nov678
Dec316

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Nga Sơn, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around September 15 and lasts for 3.7 months, ending around January 6. The clearest month is November, when the sky is clear, mostly clear, or partly cloudy 52% of the time on average.

The cloudier part of the year begins around May 16 and lasts for 4.0 months, ending around September 14. The cloudiest month is June, when it is overcast or mostly cloudy 86% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecNov 4 · 57%Jun 14 · 13%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearer
Clearer (%)Cloudier (%)
Jan2872
Feb2872
Mar2773
Apr3565
May2971
Jun1486
Jul1783
Aug1882
Sep3367
Oct5248
Nov5248
Dec4060

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 6, brings about 13 h 12 min of light; the shortest, around January 1, only 10 h 48 min — a swing of roughly 2 h 24 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.96:385:33
Feb11.36:315:50
Mar11.96:106:02
Apr12.45:436:10
May12.95:246:21
Jun13.25:206:32
Jul13.15:296:35
Aug12.75:406:21
Sep12.15:475:54
Oct11.55:555:27
Nov11.16:105:12
Dec10.86:285:16

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Nga Sơn averages about 6 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 12 days.

The sunnier stretch runs 3.8 months, from around Sep 13 to Jan 6. The sunniest month is November, with roughly 10 sunny days (mixed).

The greyest month is June, down near 3 sunny days — about 75% fewer than the November peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergloomymixedNov 312 daysJun 152 days
Sunny daysSky
Jan5Gloomy
Feb4Gloomy
Mar4Gloomy
Apr5Gloomy
May5Gloomy
Jun3Gloomy
Jul3Gloomy
Aug3Gloomy
Sep6Gloomy
Oct11Mixed
Nov10Mixed
Dec8Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Nga Sơn, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 7.6 months, from around March 19 to November 4. The muggiest month is May, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around November 5 to March 18, and December is the most comfortable month — the air is dry or comfortable 54% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecDec 21 · 58%May 7 · 0%humidoppressivemuggymiserablecomfortabledrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan4016202220
Feb27162126100
Mar10101834271
Apr139184326
May00261874
Jun0001495
Jul0000298
Aug0000298
Sep00151875
Oct1411203727
Nov11152022256
Dec3419211870

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Across the year, average wind speed in Nga Sơn is typically calm, near 12 km/h, and varies little with the seasons.

The windier part of the year lasts 3.5 months, from around Apr 7 to Jul 23. The windiest month is June, averaging about 13 km/h (light breeze).

The calmer part of the year runs from around Jul 24 to Oct 9, with September the calmest month at about 10 km/h.

05101520JanFebMarAprMayJunJulAugSepOctNovDeccalmerwindiercalmercalmlight breezeJun 28 · 13 km/hSep 1 · 9 km/h
Wind speed (km/h)Feels
Jan12light breeze
Feb12calm
Mar12calm
Apr12light breeze
May13light breeze
Jun13light breeze
Jul12light breeze
Aug10calm
Sep10calm
Oct12light breeze
Nov12light breeze
Dec12light breeze

Hazard calendar for Nga Sơn

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

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

Best time to visit Nga Sơn

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Nga Sơn throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late October, Nga Sơn is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Nga Sơn for general outdoor tourist activities is from late October to late April, with a peak score in the first week of March.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMar 6 · 7.2

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan6.5good
Feb6.9good
Mar7.1good
Apr6.6good
May4.3fair
Jun3.2poor
Jul3.1poor
Aug3.0poor
Sep3.6fair
Oct5.5fair
Nov7.0good
Dec7.0good

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best times of year to visit Nga Sơn for hot-weather activities run from mid March to late May and again from late September to early December, with a peak score in the last week of April.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationApr 22 · 6.8

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Nga Sơn, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around June (highs near 32°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 20°C), pack a light layer.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In June, Nga Sơn sees daytime highs around 32°C and nights near 28°C. Pack light clothes and rain gear. Worth having: sun protection. About 14 days see rain.

Sea temperature near Nga Sơn

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

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 (midday) in Nga Sơn by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

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

Average hourly UV index in Nga Sơn

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 8.5 hours a day reach index 3 (protection recommended), and 6.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan63
Feb6.54
Mar74.5
Apr74
May7.55
Jun8.56
Jul8.56.5
Aug86
Sep74.5
Oct6.54
Nov62.5
Dec5.51.5

Air quality in Nga Sơn by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly 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
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Nga Sơn is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Nga Sơn banks about 5,337 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around June.

02,0004,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan240
Feb248
Mar345
Apr440
May560
Jun603
Jul619
Aug594
Sep537
Oct487
Nov381
Dec284

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Nga Sơn receives about 4.1 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.5 and 5.5 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Apr 3 to Oct 11. The brightest month is June, averaging about 5.5 kWh/m² (bright).

The dimmest month is January, down near 2.6 kWh/m² — roughly 53% less than the June peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJun 35.5 kWhJan 152.5 kWh
Solar energy (kWh/m²)Level
Jan2.5Moderate
Feb2.9Moderate
Mar3.6Moderate
Apr4.8Bright
May5.4Bright
Jun5.5Bright
Jul5.3Bright
Aug4.8Bright
Sep4.4Bright
Oct4.0Bright
Nov3.4Moderate
Dec2.8Moderate

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
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).