Thanh Hóa weather in September

In September, Thanh Hóa sees average daytime highs of 31°C and overnight lows near 25°C, with 289 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 31°C through the month. The sky is clear or mostly clear about 18% 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 Thanh Hóa's 6th-clearest and 11th-windiest month. For the whole year in context, see Thanh Hóa's year-round climate.

Daytime high
31°
5th warmest
Overnight low
25°
8th coldest
Rainfall
289 mm
20.6 wet days
Daylight
12 h 06 min
5:48 AM – 5:55 PM
Cloud cover
74%
6th clearest
Wind
8 km/h
11th windiest
Solar energy
4.35 kWh/m²
Travel score
3.3
out of 10

Thanh Hóa is capital city of Thanh Hóa province.

Density
5,791/km²
people per km²
Founded
1994

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 31°C through the month.

A typical September day in Thanh Hóa reaches about 31°C in the afternoon and slips back to 25°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 34°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)
13226
23226
33226
43226
53126
63126
73126
83126
93126
103126
113126
123126
133126
143125
153125
163125
173125
183125
193125
203125
213125
223125
233125
243125
253025
263025
273025
283025
293025
303024

How September really feels in Thanh Hóa

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
6 feel dangerously hot (≥ 39°C)
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.

Thanh Hóa 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
Jan21° / 15°265.410.96.7
Feb22° / 17°153.511.37.1
Mar25° / 19°335.511.97.2
Apr29° / 23°577.212.45.8
May32° / 26°16714.612.93.4
Jun34° / 28°16713.813.22.5
Jul33° / 28°20616.313.12.6
Aug32° / 27°30921.712.72.7
Sep31° / 25°28920.612.13.3
Oct29° / 23°18015.111.55.1
Nov26° / 20°598.311.16.9
Dec22° / 16°265.110.87.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 18% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 11% of September, with mostly cloudy or overcast conditions the remaining 71%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
11882
21882
31882
41882
51882
62080
72080
82179
92179
102377
112377
122476
132674
142773
152872
162971
173070
183268
193367
203466
213565
223763
233763
243961
253961
264060
274060
284159
294159
304357

Chance of precipitation in September

Any precipitation

Thanh Hóa gets around 289 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 77% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
177
277
377
477
577
677
776
876
975
1075
1174
1273
1372
1471
1570
1669
1768
1867
1966
2065
2164
2263
2362
2462
2561
2660
2760
2860
2959
3059

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
300595
400694
511791
611890
711890
811989
9121087
10121186
11121384
12131482
13131581
14131680
15141877
16141976
17152074
18152173
19162370
20162469
21162568
22172765
23172864
24282961
25283060
26293059
27293158
282103157
293113254
303113254

Wind in September

Winds average 8 km/h in September.

Across September, daily wind ranges from about 7 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
219calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm

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 5:45 AM to 5:51 AM, and sunset from 6:09 PM to 5:41 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:456:09
212.45:456:08
312.45:456:07
412.35:456:06
512.35:466:05
612.35:466:04
712.35:466:03
812.35:466:02
912.25:466:01
1012.25:476:00
1112.25:475:59
1212.25:475:58
1312.25:475:57
1412.15:485:56
1512.15:485:56
1612.15:485:55
1712.15:485:54
1812.15:485:53
1912.15:495:52
2012.05:495:51
2112.05:495:50
2212.05:495:49
2312.05:495:48
2412.05:505:47
2511.95:505:46
2611.95:505:45
2711.95:505:44
2811.95:515:43
2911.95:515:42
3011.85:515:41

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.35 kWh/m².

For context, solar energy here swings from a low near 2.53 kWh/m² to a high of 5.47 kWh/m² in June across the year — September's 4.35 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.5Bright
24.5Bright
34.5Bright
44.4Bright
54.4Bright
64.4Bright
74.4Bright
84.3Bright
94.3Bright
104.3Bright
114.3Bright
124.3Bright
134.3Bright
144.3Bright
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
284.3Bright
294.3Bright
304.3Bright
Planning a trip in September

Hazard calendar for Thanh Hóa

In seasonPeak

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

Thanh Hóa sits in the Pacific typhoon belt; the season peaks July–October.

Thanh Hóa'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 Thanh Hóa?

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
4.9
Beach & pool
10th-best month of the year

September is a weaker month for outdoor sightseeing in Thanh Hóa.

What to pack for Thanh Hóa in September

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

In September, Thanh Hóa sees daytime highs around 31°C and nights near 25°C. Pack light clothes and rain gear. About 21 days see rain.

light clothesrain gear

Sea temperature near Thanh Hóa in September

The nearest coast averages about 30°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 23 km away) is warmest in August at about 30°C and coldest in February near 21°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
Feb21Refreshing
Mar21Refreshing
Apr24Refreshing
May28Warm
Jun29Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct28Warm
Nov26Warm
Dec23Refreshing

UV index in Thanh Hóa in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Thanh Hóa peaks around August 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 highHighAug 14UV 12Dec 15UV 6
UV index (midday)Level
Jan7Very high
Feb9Very high
Mar10Very high
Apr9Very high
May9Very high
Jun12Extreme
Jul12Extreme
Aug13Extreme
Sep10Very high
Oct9Very high
Nov7High
Dec6High

Air quality in Thanh Hóa 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 Thanh Hóa is worst in April — around 65 µg/m³ PM2.5 (unhealthy), about 3.3× the cleanest month (July, 20 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorModeratePoorUnhealthyApr 1065 µg/m³Jul 1920 µg/m³
PM2.5 (µg/m³)Level
Jan65Unhealthy
Feb63Unhealthy
Mar63Unhealthy
Apr65Unhealthy
May43Poor
Jun25Moderate
Jul20Moderate
Aug23Moderate
Sep33Moderate
Oct46Poor
Nov55Poor
Dec64Unhealthy
Location & terrain

Where is Thanh Hóa?

Thanh Hóa sits at 19.8°N, 105.8°E, 5 m above sea level, in Vietnam. The nearest listed city is Sầm Sơn, 16 km away.

Topography around Thanh Hóa

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

Within 3 km, the terrain around Thanh Hóa has only modest variations in elevation — a maximum elevation change of 76 m around an average of 6 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 271 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,521 m.

The land around Thanh Hóa is covered by artificial surfaces (55%) and trees (20%) within 3 km, cropland (51%) within 16 km, and trees (47%), water (26%) and cropland (21%) within 80 km.

3 km
76 m
16 km
271 m
80 km
1,521 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Sầm Sơn 16 km · Nga Sơn 31 km · Bỉm Sơn 32 km · Thị Trấn Lam Sơn 40 km · Nghi Sơn 53 km · Ninh Binh 56 km · Hoàng Mai 59 km · Nam Định 83 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 Thanh Hóa (19.8°, 105.7667°, elevation 5 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).