Bỉm Sơn weather in May

In May, Bỉm Sơn sees average daytime highs of 32°C and overnight lows near 25°C, with 178 mm of rain across 15.5 wet days and about 12.9 hours of daylight. It is the 4th-warmest and 4th-wettest month of the year here.

Highs climb over the month, from about 31°C in the first days to 33°C by the end. The sky is clear or mostly clear about 11% of the time in May, and the air most often feels miserable.

Daylight stretches from about 12 h 42 min at the start of May to 13 h 06 min by month's end. Set against the rest of the year, May is Bỉm Sơn's 7th-clearest and 8th-windiest month. For the whole year in context, see Bỉm Sơn's year-round climate.

Daytime high
32°
4th warmest
Overnight low
25°
9th coldest
Rainfall
178 mm
15.5 wet days
Daylight
12 h 54 min
5:24 AM – 6:21 PM
Cloud cover
77%
7th clearest
Wind
8 km/h
8th windiest
Solar energy
5.23 kWh/m²
Travel score
3.3
out of 10

Bỉm Sơn is district-level town in Thanh Hóa province, Vietnam.

Density
802/km²
people per km²
Founded
1981

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs climb over the month, from about 31°C in the first days to 33°C by the end.

A typical May day in Bỉm Sơn reaches about 32°C in the afternoon and slips back to 25°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 37°C. Set against its neighbours, May runs about 3°C warmer than April and about 2°C cooler than June.

20°25°30°35°40°151015202531
Avg high (°C)Avg low (°C)
13124
23124
33124
43124
53225
63225
73225
83225
93225
103225
113225
123225
133225
143225
153225
163225
173225
183225
193326
203326
213326
223326
233326
243326
253326
263326
273326
283326
293326
303326
313326

How May really feels in Bỉm Sơn

Once humidity and wind are folded in, May averages 31 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
31
15 feel dangerously hot (≥ 39°C)
Days feeling ≤ C
0
wind chill below the day's low

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

Bỉm Sơn weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan21° / 15°295.610.96.7
Feb22° / 16°174.411.37.0
Mar25° / 19°356.711.97.0
Apr29° / 22°648.612.45.5
May32° / 25°17815.512.93.3
Jun34° / 27°17814.613.22.5
Jul33° / 27°23417.813.12.5
Aug32° / 26°3242312.72.6
Sep31° / 25°27820.812.13.2
Oct29° / 23°15614.511.55.1
Nov26° / 19°577.9116.9
Dec22° / 16°255.410.87.1

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 14% of May, with mostly cloudy or overcast conditions the remaining 75%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12971
22971
32971
43070
53070
63070
73070
83070
93070
103070
113070
123070
132971
142872
152872
162674
172674
182476
192476
202377
212278
222179
231981
241981
251882
261882
271783
281783
291684
301684
311684

Chance of precipitation in May

Any precipitation

Bỉm Sơn gets around 178 mm of rain over 15.5 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 49% and peaks near 57% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
137
238
339
440
541
641
742
843
944
1045
1146
1247
1348
1449
1550
1651
1751
1852
1953
2053
2154
2255
2355
2456
2557
2657
2757
2857
2957
3057
3157

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the miserable band about 69% of days. Sticky, muggy-or-worse air turns up on roughly 98% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
14113352
24103254
33103255
4393157
5393058
6382960
7382861
8382762
9272665
10272566
11272566
12272467
13272368
14272368
15272269
16272269
17272170
18262171
19162172
20162073
21162073
22161974
23151975
24151876
25151876
26141778
27141679
28141679
29031582
30031483
31021484

Wind in May

Winds average 8 km/h in May.

Across May, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 42 min at the start of May to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 24 minutes over May. Sunrise moves from 5:32 AM to 5:20 AM, and sunset from 6:15 PM to 6:27 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:326:15
212.75:316:16
312.85:316:16
412.85:306:17
512.85:306:17
612.85:296:17
712.85:296:18
812.85:286:18
912.85:276:18
1012.95:276:19
1112.95:266:19
1212.95:266:20
1312.95:266:20
1412.95:256:20
1512.95:256:21
1612.95:246:21
1713.05:246:22
1813.05:246:22
1913.05:236:23
2013.05:236:23
2113.05:236:23
2213.05:226:24
2313.05:226:24
2413.05:226:25
2513.15:226:25
2613.15:216:25
2713.15:216:26
2813.15:216:26
2913.15:216:27
3013.15:216:27
3113.15:206:27

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.23 kWh/m².

For context, solar energy here swings from a low near 2.43 kWh/m² to a high of 5.33 kWh/m² in June across the year — May's 5.23 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.1Bright
45.2Bright
55.2Bright
65.2Bright
75.2Bright
85.2Bright
95.2Bright
105.2Bright
115.2Bright
125.2Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.2Bright
185.2Bright
195.2Bright
205.2Bright
215.2Bright
225.2Bright
235.2Bright
245.3Bright
255.3Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
315.3Bright
Planning a trip in May

Hazard calendar for Bỉm Sơn

In seasonPeak

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

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

Bỉm 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 May a good time to visit Bỉm Sơn?

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

3.3
Sightseeing
8th-best month of the year
5.4
Beach & pool
5th-best month of the year

May is a weaker month for outdoor sightseeing in Bỉm Sơn.

What to pack for Bỉm Sơn in May

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

In May, Bỉm Sơn sees daytime highs around 32°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 16 days see rain.

light clothesrain gearsun protection

Sea temperature near Bỉm Sơn in May

The nearest coast averages about 28°C in May — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 36 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 Bỉm Sơn in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Bỉm 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 Bỉm Sơn in May

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Bỉm 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 Bỉm Sơn?

Bỉm Sơn sits at 20.1°N, 105.9°E, 7 m above sea level, in Vietnam. The nearest listed city is Nga Sơn, 14 km away.

Topography around Bỉm Sơn

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

Within 3 km, the terrain around Bỉm Sơn has only modest variations in elevation — a maximum elevation change of 99 m around an average of 13 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 327 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,500 m.

The land around Bỉm Sơn is covered by trees (39%) and cropland (27%) within 3 km, trees (52%) and cropland (33%) within 16 km, and trees (41%), cropland (29%) and water (23%) within 80 km.

3 km
99 m
16 km
327 m
80 km
1,500 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Nga Sơn 14 km · Ninh Binh 24 km · Thanh Hóa 32 km · Sầm Sơn 39 km · Thị Trấn Lam Sơn 51 km · Nam Định 52 km · Phủ Lý 52 km · Thái Bình 65 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 Bỉm Sơn (20.0781°, 105.8603°, elevation 7 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).