Ha Long weather in December

In December, Ha Long sees average daytime highs of 21°C and overnight lows near 16°C, with 31 mm of rain across 5.9 wet days and about 10.8 hours of daylight. It is the 10th-warmest and 11th-wettest month of the year here.

Highs ease over the month, from about 23°C in the first days to 20°C by the end. The sky is clear or mostly clear about 29% 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 Ha Long's 3rd-clearest and 4th-windiest month. For the whole year in context, see Ha Long's year-round climate.

Daytime high
21°
10th warmest
Overnight low
16°
3rd coldest
Rainfall
31 mm
5.9 wet days
Daylight
10 h 42 min
6:26 AM – 5:10 PM
Cloud cover
62%
3rd clearest
Wind
11 km/h
4th windiest
Solar energy
2.88 kWh/m²
Travel score
7.0
out of 10

Ha Long is provincial city of Vietnam.

Air quality
Elevated
PM10 47 µg/m³ · 2015
Density
993/km²
people per km²

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 23°C in the first days to 20°C by the end.

A typical December day in Ha Long reaches about 21°C in the afternoon and slips back to 16°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 25°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)
12317
22317
32317
42217
52217
62217
72217
82216
92216
102216
112116
122116
132116
142116
152116
162116
172115
182115
192115
202115
212115
222115
232115
242015
252015
262015
272015
282015
292015
302015
312015

How December really feels in Ha Long

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.

Ha Long 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
Jan19° / 15°346.510.96.3
Feb20° / 16°215.611.36.4
Mar22° / 18°448.811.96.5
Apr26° / 22°6911.612.56.0
May30° / 25°21919.5133.9
Jun31° / 27°26622.413.22.9
Jul31° / 27°30524.313.12.8
Aug31° / 26°38126.212.72.7
Sep30° / 25°2432012.13.6
Oct28° / 23°10411.911.55.7
Nov25° / 19°518.2117.1
Dec21° / 16°315.910.87.0

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 12% of December, with mostly cloudy or overcast conditions the remaining 59%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14753
24555
34555
44357
54258
64258
74159
84060
93961
103862
113862
123961
133961
143961
154060
164060
173961
184159
194159
204159
214258
224258
234258
244159
254159
264159
274060
284060
293961
303763
313664

Chance of precipitation in December

Any precipitation

Ha Long gets around 31 mm of rain over 5.9 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 20% and peaks near 24% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
124
223
323
422
522
622
721
821
921
1020
1120
1220
1319
1419
1519
1619
1719
1819
1919
2018
2118
2218
2318
2418
2518
2618
2718
2819
2919
3019
3119

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 45% of days. Sticky, muggy-or-worse air turns up on roughly 16% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
13319221781
23419221781
33519221671
43719211670
53820211560
63920201460
74021201460
84121191350
94321181350
104421181240
114521181240
124621171240
134721171240
144721161230
154821161230
164821161230
174821151230
184921151230
194921151230
204921161230
214921161120
224922161120
234922171020
244922171020
254922181020
264822191010
274822191010
284722201010
294722211010
304622221010
314621221010

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
111calm
211calm
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 6:17 AM to 6:33 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)
110.86:175:06
210.86:185:06
310.86:185:06
410.86:195:06
510.86:195:07
610.86:205:07
710.86:215:07
810.86:215:07
910.86:225:08
1010.86:225:08
1110.86:235:08
1210.76:245:08
1310.76:245:09
1410.76:255:09
1510.76:255:09
1610.76:265:10
1710.76:265:10
1810.76:275:11
1910.76:275:11
2010.76:285:12
2110.76:285:12
2210.76:295:12
2310.76:295:13
2410.76:305:13
2510.76:305:14
2610.76:315:14
2710.76:315:15
2810.76:315:15
2910.76:325:16
3010.76:325:17
3110.76:335:17

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.88 kWh/m².

For context, solar energy here swings from a low near 2.58 kWh/m² to a high of 5.07 kWh/m² in May across the year — December's 2.88 kWh/m² sits near the bottom.

01234151015202531
Solar energy (kWh/m²)Level
13.0Moderate
23.0Moderate
33.0Moderate
43.0Moderate
53.0Moderate
62.9Moderate
72.9Moderate
82.9Moderate
92.9Moderate
102.9Moderate
112.9Moderate
122.8Moderate
132.8Moderate
142.8Moderate
152.8Moderate
162.9Moderate
172.9Moderate
182.9Moderate
192.9Moderate
202.9Moderate
212.9Moderate
222.9Moderate
232.9Moderate
242.9Moderate
252.9Moderate
262.9Moderate
272.8Moderate
282.8Moderate
292.8Moderate
302.8Moderate
312.8Moderate
Planning a trip in December

Hazard calendar for Ha Long

In seasonPeak

In December, Ha Long sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Ha Long sits in the Pacific typhoon belt; the season peaks July–October.

Ha Long's monsoon runs May–September, when most of the year's rain falls.

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

Is December a good time to visit Ha Long?

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

7.0
Sightseeing
2nd-best month of the year
4.4
Beach & pool
7th-best month of the year

December is one of the better times to visit Ha Long for general sightseeing.

What to pack for Ha Long in December

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

In December, Ha Long sees daytime highs around 21°C and nights near 16°C. Little to plan around — just the basics. About 6 days see rain.

Sea temperature near Ha Long in December

The nearest coast averages about 22°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 32 km away) is warmest in August at about 30°C and coldest in February near 19°C.

It's comfortable for a long swim from Mar 13 to Jan 10 — about 10 months when the water holds above 20°C.

20°25°30°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan20Cool
Feb19Cool
Mar20Refreshing
Apr23Refreshing
May27Warm
Jun29Tropical
Jul29Tropical
Aug30Tropical
Sep29Tropical
Oct28Warm
Nov25Warm
Dec22Refreshing

UV index in Ha Long 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 Ha Long peaks around July 12 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 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 12UV 12Dec 19UV 6
UV index (midday)Level
Jan7High
Feb8Very high
Mar9Very high
Apr8Very high
May10Extreme
Jun12Extreme
Jul12Extreme
Aug9Very high
Sep9Very high
Oct9Very high
Nov7High
Dec6High

Air quality in Ha Long 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 Ha Long is worst in January — around 42 µg/m³ PM2.5 (poor), about 2.6× the cleanest month (July, 16 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorModeratePoorJan 2342 µg/m³Jul 1716 µg/m³
PM2.5 (µg/m³)Level
Jan42Poor
Feb42Poor
Mar41Poor
Apr40Poor
May26Moderate
Jun19Moderate
Jul16Moderate
Aug18Moderate
Sep21Moderate
Oct27Moderate
Nov29Moderate
Dec39Poor
Location & terrain

Where is Ha Long?

Ha Long sits at 21.0°N, 107.1°E, 8 m above sea level, in Vietnam. The nearest listed city is Cẩm Phả, 22 km away.

Topography around Ha Long

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

Within 3 km, the terrain around Ha Long has only modest variations in elevation — a maximum elevation change of 150 m around an average of 9 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 679 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,530 m.

The land around Ha Long is covered by water (57%) and artificial surfaces (21%) within 3 km, water (46%) and trees (37%) within 16 km, and trees (42%) and water (42%) within 80 km.

3 km
150 m
16 km
679 m
80 km
1,530 m
treesgrasslandcroplandartificial surfacesbare terrainwatermangroves
December weather nearby: Cẩm Phả 22 km · Cẩm Phả Mines 25 km · Cát Bà 25 km · Thành Phố Uông Bí 33 km · Đố Sơn 40 km · Haiphong 42 km · Thị Trấn Ba Chẽ 42 km · Kiến An 49 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 Ha Long (20.9505°, 107.0734°, 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).