Lạng Sơn weather in December

In December, Lạng Sơn sees average daytime highs of 19°C and overnight lows near 12°C, with 45 mm of rain across 8.2 wet days and about 10.7 hours of daylight. It is the 10th-warmest and 11th-wettest month of the year here.

Highs ease over the month, from about 21°C in the first days to 18°C by the end. The sky is clear or mostly clear about 28% of the time in December, and the air most often feels dry.

Daylight stretches from about 10 h 48 min at the start of December to 10 h 42 min by month's end. Set against the rest of the year, December is Lạng Sơn's 3rd-clearest and 2nd-windiest month. For the whole year in context, see Lạng Sơn's year-round climate.

Daytime high
19°
10th warmest
Overnight low
12°
2nd coldest
Rainfall
45 mm
8.2 wet days
Daylight
10 h 42 min
6:29 AM – 5:09 PM
Cloud cover
62%
3rd clearest
Wind
11 km/h
2nd windiest
Solar energy
2.68 kWh/m²
Travel score
6.3
out of 10

Lạng Sơn is provincial city of Vietnam.

Density
2,533/km²
people per km²
Founded
2002

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 21°C in the first days to 18°C by the end.

A typical December day in Lạng Sơn reaches about 19°C in the afternoon and slips back to 12°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 13°C and 24°C. Set against its neighbours, December runs about 4°C cooler than November and about 2°C warmer than January.

10°15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12114
22114
32114
42014
52014
62013
72013
82013
92013
102013
111913
121913
131913
141912
151912
161912
171912
181912
191912
201912
211912
221912
231912
241912
251912
261912
271812
281812
291812
301812
311812

How December really feels in Lạng Sơn

Once humidity and wind are folded in, December averages 0 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Lạng Sơn weather by month

How December compares with the rest of the year at a glance. December is the 10th-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan17° / 11°5711.110.85.1
Feb19° / 13°4410.111.25.6
Mar21° / 16°7914.411.85.5
Apr26° / 20°9714.912.55.5
May29° / 23°22121.2134.0
Jun30° / 25°25723.613.33.0
Jul31° / 25°27024.913.22.9
Aug30° / 24°28525.312.73.0
Sep29° / 23°16418.312.14.2
Oct27° / 20°7510.911.56.4
Nov23° / 16°507.9117.1
Dec19° / 12°458.210.76.3

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 28% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 11% of December, with mostly cloudy or overcast conditions the remaining 61%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14456
24357
34357
44258
54159
64060
73961
83961
93862
103862
113862
123961
133961
144060
154060
164060
174159
184159
194060
204159
214159
224258
234258
244159
254060
263961
273862
283664
293565
303466
313169

Chance of precipitation in December

Any precipitation

Lạng Sơn gets around 45 mm of rain over 8.2 wet days in December. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 27% and peaks near 31% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
127
228
328
428
528
627
727
827
927
1027
1126
1226
1325
1425
1525
1625
1725
1825
1925
2025
2125
2225
2325
2426
2526
2627
2727
2828
2929
3030
3131

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the dry band about 64% of days. Sticky, muggy-or-worse air turns up on roughly 7% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1502116112
2522016102
354191692
455191682
556181682
658171672
759171572
862161561
963151561
1064151461
1165141461
1265141461
1367141360
1467141360
1567141360
1667141360
1768141260
1867151260
1968151160
2068151160
2167161160
2268161150
2368171050
2467171150
2567181140
2667181140
2765191240
2866191230
2965191330
3065191330
3164191430

Wind in December

Winds average 11 km/h in December.

Across December, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
311calm
411calm
511calm
611calm
711calm
811calm
911calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 10 h 48 min at the start of December to 10 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 6 minutes over December. Sunrise moves from 6:20 AM to 6:36 AM, and sunset from 5:06 PM to 5:17 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.86:205:06
210.86:215:06
310.76:215:06
410.76:225:06
510.76:225:06
610.76:235:06
710.76:245:07
810.76:245:07
910.76:255:07
1010.76:255:07
1110.76:265:08
1210.76:275:08
1310.76:275:08
1410.76:285:09
1510.76:285:09
1610.76:295:09
1710.76:295:10
1810.76:305:10
1910.76:315:11
2010.76:315:11
2110.76:325:11
2210.76:325:12
2310.76:325:12
2410.76:335:13
2510.76:335:13
2610.76:345:14
2710.76:345:14
2810.76:355:15
2910.76:355:15
3010.76:355:16
3110.76:365:17

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.68 kWh/m².

For context, solar energy here swings from a low near 2.23 kWh/m² to a high of 4.72 kWh/m² in July across the year — December's 2.68 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.8Moderate
22.8Moderate
32.8Moderate
42.8Moderate
52.7Moderate
62.7Moderate
72.7Moderate
82.7Moderate
92.7Moderate
102.7Moderate
112.7Moderate
122.7Moderate
132.7Moderate
142.7Moderate
152.7Moderate
162.7Moderate
172.7Moderate
182.7Moderate
192.7Moderate
202.7Moderate
212.7Moderate
222.7Moderate
232.7Moderate
242.7Moderate
252.7Moderate
262.6Moderate
272.6Moderate
282.6Moderate
292.6Moderate
302.5Moderate
312.5Moderate
Planning a trip in December

Hazard calendar for Lạng Sơn

In seasonPeak

None of Lạng Sơn's seasonal hazards are active in December. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Lạng Sơn'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 December a good time to visit Lạng Sơn?

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

6.3
Sightseeing
3rd-best month of the year
2.9
Beach & pool
10th-best month of the year

December is a reasonable time to visit Lạng Sơn for sightseeing.

What to pack for Lạng Sơn in December

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

In December, Lạng Sơn sees daytime highs around 19°C and nights near 12°C. Worth packing: rain gear. About 8 days see rain.

rain gear

UV index in Lạng Sơn in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Lạng Sơn peaks around June 23 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 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 highHighJun 23UV 12Dec 14UV 6
UV index (midday)Level
Jan6High
Feb7High
Mar9Very high
Apr7High
May9Very high
Jun12Extreme
Jul12Extreme
Aug10Extreme
Sep10Very high
Oct8Very high
Nov6High
Dec6High

Air quality in Lạng Sơn in December

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Lạng Sơn is worst in December — around 58 µg/m³ PM2.5 (unhealthy), about 2.3× the cleanest month (July, 25 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorModeratePoorUnhealthyDec 2358 µg/m³Jul 1625 µg/m³
PM2.5 (µg/m³)Level
Jan57Unhealthy
Feb55Unhealthy
Mar55Poor
Apr54Poor
May37Poor
Jun29Moderate
Jul25Moderate
Aug29Moderate
Sep36Poor
Oct43Poor
Nov50Poor
Dec58Unhealthy
Location & terrain

Where is Lạng Sơn?

Lạng Sơn sits at 21.9°N, 106.8°E, 265 m above sea level, in Vietnam. The nearest listed city is Thị Trấn Na Dương, 26 km away.

Topography around Lạng Sơn

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

Within 3 km, the terrain around Lạng Sơn has only modest variations in elevation — a maximum elevation change of 171 m around an average of 282 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 978 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,481 m.

The land around Lạng Sơn is covered by trees (46%) and artificial surfaces (32%) within 3 km, trees (80%) within 16 km, and trees (89%) within 80 km.

3 km
171 m
16 km
978 m
80 km
1,481 m
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Thị Trấn Na Dương 26 km · Thị Trấn Thất Khê 54 km · Chũ 57 km · Thị Trấn Ba Chẽ 84 km · Bắc Giang 87 km · Thị Trấn Tiên Yên 88 km · Thị Trấn Đông Triều 89 km · Thị Trấn Mạo Khê 90 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 Lạng Sơn (21.8526°, 106.761°, elevation 265 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).