Thành phố Sông Công weather in September

In September, Thành phố Sông Công sees average daytime highs of 31°C and overnight lows near 25°C, with 227 mm of rain across 19 wet days and about 12.1 hours of daylight. It is the 4th-warmest and 5th-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 22% 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 Thành phố Sông Công's 4th-clearest and 11th-windiest month. For the whole year in context, see Thành phố Sông Công's year-round climate.

Daytime high
31°
4th warmest
Overnight low
25°
9th coldest
Rainfall
227 mm
19 wet days
Daylight
12 h 06 min
5:47 AM – 5:55 PM
Cloud cover
70%
4th clearest
Wind
5 km/h
11th windiest
Solar energy
4.36 kWh/m²
Travel score
3.4
out of 10

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 Thành phố Sông Công reaches about 31°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 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)
13225
23225
33225
43225
53225
63225
73225
83225
93225
103125
113125
123125
133125
143125
153125
163125
173125
183124
193124
203124
213124
223124
233124
243124
253124
263124
273124
283124
293124
303124

How September really feels in Thành phố Sông Công

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.

Thành phố Sông Công weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan19° / 14°5911.210.85.7
Feb21° / 15°471111.35.8
Mar24° / 18°8214.911.85.7
Apr28° / 21°11714.812.55.0
May31° / 24°26819.7133.3
Jun33° / 26°34521.313.32.5
Jul32° / 26°35323.813.22.4
Aug32° / 26°38024.612.72.5
Sep31° / 25°2271912.13.4
Oct29° / 22°10712.211.55.3
Nov26° / 18°627.7117.0
Dec21° / 15°418.110.76.7

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 66%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12476
22476
32476
42575
52575
62476
72575
82773
92773
102971
112971
123070
133169
143268
153466
163565
173664
183664
193862
203862
214060
224159
234258
244258
254456
264555
274555
284555
294654
304654

Chance of precipitation in September

Any precipitation

Thành phố Sông Công gets around 227 mm of rain over 19 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 63% 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
476
576
675
775
874
973
1071
1170
1269
1367
1466
1564
1662
1761
1859
1958
2056
2155
2254
2353
2452
2551
2651
2750
2849
2949
3048

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 66% of days. Sticky, muggy-or-worse air turns up on roughly 98% of them.

0%25%50%75%100%151015202530
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
100892
200991
3011089
4011089
5111187
6111286
7121384
8121483
9121582
10131680
11131878
12141976
13142075
14152173
15162370
16172468
17272566
18282763
19292861
202103058
212113156
222123353
232133451
242143648
253153745
263153843
274164040
284174138
295184236
305184234

Wind in September

Winds average 5 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

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 5:43 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)
112.45:436:09
212.45:446:08
312.45:446:07
412.45:446:06
512.45:446:06
612.35:456:05
712.35:456:04
812.35:456:03
912.35:456:02
1012.25:466:01
1112.25:466:00
1212.25:465:59
1312.25:475:58
1412.25:475:57
1512.15:475:56
1612.15:475:55
1712.15:485:54
1812.15:485:53
1912.15:485:52
2012.05:485:51
2112.05:495:50
2212.05:495:49
2312.05:495:48
2412.05:495:47
2511.95:505:46
2611.95:505:45
2711.95:505:44
2811.95:515:43
2911.85:515:42
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 4.36 kWh/m².

For context, solar energy here swings from a low near 2.08 kWh/m² to a high of 4.68 kWh/m² in June across the year — September's 4.36 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.4Bright
24.4Bright
34.3Bright
44.3Bright
54.3Bright
64.3Bright
74.3Bright
84.3Bright
94.3Bright
104.3Bright
114.3Bright
124.3Bright
134.3Bright
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
284.3Bright
294.3Bright
304.3Bright
Planning a trip in September

Hazard calendar for Thành phố Sông Công

In seasonPeak

In September, Thành phố Sông Công sits inside its monsoon season. The full year is below, with each hazard's peak months called out.

Thành phố Sông Công's monsoon runs May–September, when most of the year's rain falls.

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

Is September a good time to visit Thành phố Sông Công?

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

3.4
Sightseeing
8th-best month of the year
5.1
Beach & pool
4th-best month of the year

September is a weaker month for outdoor sightseeing in Thành phố Sông Công.

What to pack for Thành phố Sông Công in September

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

In September, Thành phố Sông Công sees daytime highs around 31°C and nights near 25°C. Pack light clothes and rain gear. About 19 days see rain.

light clothesrain gear

UV index in Thành phố Sông Công in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Thành phố Sông Công peaks around July 11 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 23 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highVery highExtremeVery highHighJul 11UV 11Nov 23UV 6
UV index (midday)Level
Jan6High
Feb7High
Mar9Very high
Apr6High
May9Very high
Jun11Extreme
Jul11Extreme
Aug10Very high
Sep8Very high
Oct8Very high
Nov6High
Dec6High

Air quality in Thành phố Sông Công 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 Thành phố Sông Công is worst in December — around 102 µg/m³ PM2.5 (unhealthy), about 2.8× the cleanest month (July, 37 µg/m³).

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

0306090120JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorUnhealthyDec 20102 µg/m³Jul 1738 µg/m³
PM2.5 (µg/m³)Level
Jan98Unhealthy
Feb89Unhealthy
Mar86Unhealthy
Apr79Unhealthy
May57Unhealthy
Jun44Poor
Jul37Poor
Aug44Poor
Sep59Unhealthy
Oct76Unhealthy
Nov92Unhealthy
Dec102Unhealthy
Location & terrain

Where is Thành phố Sông Công?

Thành phố Sông Công sits at 21.5°N, 105.8°E, 28 m above sea level, in Vietnam. The nearest listed city is Phổ Yên, 8.0 km away.

Topography around Thành phố Sông Công

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Thành phố Sông Công.

Within 3 km, the terrain around Thành phố Sông Công has only modest variations in elevation — a maximum elevation change of 66 m around an average of 24 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,304 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,720 m.

The land around Thành phố Sông Công is covered by trees (52%) and cropland (27%) within 3 km, trees (64%) and cropland (23%) within 16 km, and trees (69%) and cropland (21%) within 80 km.

3 km
66 m
16 km
1,304 m
80 km
1,720 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Phổ Yên 8.0 km · Thái Nguyên 13 km · Sóc Sơn 24 km · Thị Trấn Đại Từ 27 km · Phúc Yên 30 km · Vĩnh Yên 31 km · Quang Minh 33 km · Việt Yên 38 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 Thành phố Sông Công (21.4772°, 105.8414°, elevation 28 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. 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).