Cổ Đô weather in December

In December, Cổ Đô sees average daytime highs of 21°C and overnight lows near 15°C, with 38 mm of rain across 7.6 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 23°C in the first days to 20°C by the end. The sky is clear or mostly clear about 27% 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 Cổ Đô's 3rd-clearest and 12th-windiest month. For the whole year in context, see Cổ Đô's year-round climate.

Daytime high
21°
10th warmest
Overnight low
15°
2nd coldest
Rainfall
38 mm
7.6 wet days
Daylight
10 h 42 min
6:33 AM – 5:16 PM
Cloud cover
62%
3rd clearest
Wind
4 km/h
12th windiest
Solar energy
2.56 kWh/m²
Travel score
6.8
out of 10

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 Cổ Đô reaches about 21°C in the afternoon and slips back to 15°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 26°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
42216
52216
62216
72216
82216
92216
102216
112115
122115
132115
142115
152115
162115
172115
182115
192115
202114
212114
222114
232114
242114
252014
262014
272014
282014
292014
302014
312014

How December really feels in Cổ Đô

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.

Cổ Đô 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° / 14°459.110.86.0
Feb21° / 15°348.511.36.3
Mar24° / 18°6111.611.86.3
Apr29° / 22°10312.212.55.2
May31° / 25°23017.9133.4
Jun33° / 26°23819.113.32.6
Jul33° / 26°29120.913.22.6
Aug32° / 26°35422.512.72.7
Sep31° / 25°23018.812.13.5
Oct29° / 22°11911.611.55.6
Nov25° / 19°587.5117.1
Dec21° / 15°387.610.76.8

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 15% of December, with mostly cloudy or overcast conditions the remaining 58%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14456
24357
34357
44357
54258
64258
74159
84159
94159
104258
114258
124357
134456
144456
154555
164456
174555
184555
194555
204555
214555
224456
234357
244357
254357
264159
273961
283862
293664
303565
313367

Chance of precipitation in December

Any precipitation

Cổ Đô gets around 38 mm of rain over 7.6 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 24% and peaks near 27% on the wettest days.

0%10%20%30%40%151015202531
Rain chance (%)
125
225
325
425
525
625
725
825
925
1025
1125
1224
1324
1424
1523
1623
1723
1822
1922
2022
2122
2222
2323
2423
2523
2624
2724
2825
2925
3026
3127

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 35% of days. Sticky, muggy-or-worse air turns up on roughly 14% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1192530197
2202630186
3212630175
4222729175
5242729165
6252828154
7262827154
8272927143
9292926143
10302925142
11322924142
12332823142
13352823141
14362722141
15372622141
16392622131
17402522131
18402522130
19412422120
20422422120
21422422110
22432323110
23432323100
24432324100
2543232590
2642232690
2742232680
2841232780
2941232890
3040232890
3140232890

Wind in December

Winds average 4 km/h in December, the calmest month.

Across December, daily wind ranges from about 4 km/h on the calmest days to 4 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

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 6:24 AM to 6:40 AM, and sunset from 5:12 PM to 5:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
110.86:245:12
210.86:255:12
310.86:265:12
410.86:265:13
510.86:275:13
610.86:285:13
710.86:285:13
810.76:295:14
910.76:295:14
1010.76:305:14
1110.76:315:14
1210.76:315:15
1310.76:325:15
1410.76:325:15
1510.76:335:16
1610.76:335:16
1710.76:345:16
1810.76:345:17
1910.76:355:17
2010.76:355:18
2110.76:365:18
2210.76:365:19
2310.76:375:19
2410.76:375:20
2510.76:385:20
2610.76:385:21
2710.76:395:21
2810.76:395:22
2910.76:395:22
3010.76:405:23
3110.76:405:23

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 2.56 kWh/m².

For context, solar energy here swings from a low near 2.16 kWh/m² to a high of 4.77 kWh/m² in June across the year — December's 2.56 kWh/m² sits near the bottom.

0123151015202531
Solar energy (kWh/m²)Level
12.6Moderate
22.6Moderate
32.6Moderate
42.6Moderate
52.6Moderate
62.6Moderate
72.6Moderate
82.6Moderate
92.5Moderate
102.5Moderate
112.5Moderate
122.5Moderate
132.6Moderate
142.6Moderate
152.6Moderate
162.6Moderate
172.6Moderate
182.6Moderate
192.6Moderate
202.6Moderate
212.6Moderate
222.6Moderate
232.6Moderate
242.6Moderate
252.6Moderate
262.5Moderate
272.5Moderate
282.5Moderate
292.5Moderate
302.4Moderate
312.4Moderate
Planning a trip in December

Hazard calendar for Cổ Đô

In seasonPeak

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

Cổ Đô sits in the Pacific typhoon belt; the season peaks July–October.

Cổ Đô'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 Cổ Đô?

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

6.8
Sightseeing
2nd-best month of the year
4.3
Beach & pool
10th-best month of the year

December is a reasonable time to visit Cổ Đô for sightseeing.

What to pack for Cổ Đô in December

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

In December, Cổ Đô sees daytime highs around 21°C and nights near 15°C. Little to plan around — just the basics. About 8 days see rain.

UV index in Cổ Đô 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 Cổ Đô peaks around June 20 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 20 at about 5 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highHighVery highExtremeHighJun 20UV 12Nov 20UV 5
UV index (midday)Level
Jan6High
Feb7High
Mar8Very high
Apr6High
May8Very high
Jun12Extreme
Jul11Extreme
Aug11Extreme
Sep6High
Oct7Very high
Nov5High
Dec6High

Air quality in Cổ Đô 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 Cổ Đô is worst in April — around 98 µg/m³ PM2.5 (unhealthy), about 3.8× the cleanest month (July, 26 µg/m³).

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

0306090120JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorModeratePoorUnhealthyApr 1494 µg/m³Jul 2026 µg/m³
PM2.5 (µg/m³)Level
Jan76Unhealthy
Feb71Unhealthy
Mar76Unhealthy
Apr98Unhealthy
May57Unhealthy
Jun32Moderate
Jul26Moderate
Aug28Moderate
Sep39Poor
Oct53Poor
Nov66Unhealthy
Dec77Unhealthy
Location & terrain

Where is Cổ Đô?

Cổ Đô sits at 21.3°N, 105.4°E, 17 m above sea level, in Vietnam. The nearest listed city is Việt Trì, 6.0 km away.

Topography around Cổ Đô

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

Within 3 km, the terrain around Cổ Đô has only modest variations in elevation — a maximum elevation change of 22 m around an average of 13 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 333 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,211 m.

The land around Cổ Đô is covered by cropland (39%) within 3 km, trees (42%) and cropland (33%) within 16 km, and trees (72%) within 80 km.

3 km
22 m
16 km
333 m
80 km
2,211 m
treesgrasslandcroplandartificial surfacesbare terrainwater
December weather nearby: Việt Trì 6.0 km · Phú Thọ 20 km · Sơn Tây 21 km · Ba Vì 22 km · Vĩnh Yên 25 km · Phúc Yên 36 km · Đan Phượng 37 km · Thượng Cát 43 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 Cổ Đô (21.2796°, 105.364°, elevation 17 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). 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).