Cổ Đô in Winter
In winter (December, January and February), Cổ Đô sees average daytime highs around 21°C and overnight lows near 15°C, with 117 mm of rain over about 25 wet days across the season. It is the coldest season of the year and the driest season of the year.
Across winter, daytime highs hold fairly steady around 21°C. The sky is clear or mostly clear about 17% of the time across winter, and the air most often feels dry.
Winter is Cổ Đô's best season of the year to visit on our travel score. For the whole year in context, see Cổ Đô's year-round climate.
- Avg daytime high
- 21°C
- coldest season of the year
- Avg overnight low
- 15°C
- Rainfall
- 117 mm
- 25 wet days
- Avg wind
- 5 km/h
- Travel score
- 6.4
- best season of the year
- Months
- Dec · Jan · Feb
Temperature in Cổ Đô in Winter
Across winter, daytime highs hold fairly steady around 21°C.
A typical winter day in Cổ Đô reaches about 21°C and drops to 15°C overnight. The warmest of the three months is December, the coolest January.
How winter really feels in Cổ Đô
Once humidity and wind are folded in, winter brings about 0 days that feel above 32°C and 0 that feel at or below 0°C.
winter 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 the three winter months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 19° / 14° | 45 | 9.1 | 10.8 | 6.0 |
| Feb | 21° / 15° | 34 | 8.5 | 11.3 | 6.3 |
| Mar | 24° / 18° | 61 | 11.6 | 11.8 | 6.3 |
| Apr | 29° / 22° | 103 | 12.2 | 12.5 | 5.2 |
| May | 31° / 25° | 230 | 17.9 | 13 | 3.4 |
| Jun | 33° / 26° | 238 | 19.1 | 13.3 | 2.6 |
| Jul | 33° / 26° | 291 | 20.9 | 13.2 | 2.6 |
| Aug | 32° / 26° | 354 | 22.5 | 12.7 | 2.7 |
| Sep | 31° / 25° | 230 | 18.8 | 12.1 | 3.5 |
| Oct | 29° / 22° | 119 | 11.6 | 11.5 | 5.6 |
| Nov | 25° / 19° | 58 | 7.5 | 11 | 7.1 |
| Dec | 21° / 15° | 38 | 7.6 | 10.7 | 6.8 |
Cloud cover in Winter
The sky is clear or mostly clear about 17% of the time across winter.
Chance of precipitation in Winter
Cổ Đô gets around 117 mm of rain over 25 wet days across winter. The line is the day-by-day chance of measurable precipitation.
Humidity in Winter
Most of winter feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Winter
Winds average 5 km/h across winter.
Sunrise & sunset in Winter
Daylight runs from about 10 h 48 min in early December to 11 h 30 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Winter
Average shortwave solar energy reaching the ground each day across winter, about 2.4 kWh/m².
Hazard calendar for Cổ Đô
In winter, Cổ Đô overlaps 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.
Is winter a good time to visit Cổ Đô?
Our two travel scores rate winter for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
winter is a reasonable time to visit Cổ Đô for sightseeing.
What to pack for Cổ Đô in Winter
From winter's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In winter, Cổ Đô sees daytime highs around 21°C and nights near 15°C. Worth packing: rain gear. About 25 days see rain.
UV index in Cổ Đô in Winter
Clear-sky midday UV across winter averages 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.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 6 | 7 | 8 | 6 | 8 | 12 | 11 | 11 | 6 | 7 | 5 | 6 |
| Level | High | High | Very high | High | Very high | Extreme | Extreme | Extreme | High | Very high | High | High |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 6 | High |
| Feb | 7 | High |
| Mar | 8 | Very high |
| Apr | 6 | High |
| May | 8 | Very high |
| Jun | 12 | Extreme |
| Jul | 11 | Extreme |
| Aug | 11 | Extreme |
| Sep | 6 | High |
| Oct | 7 | Very high |
| Nov | 5 | High |
| Dec | 6 | High |
Air quality in Cổ Đô in Winter
Average fine-particle pollution (PM2.5) through the year — so you can see where winter 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).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 76 | 71 | 76 | 98 | 57 | 32 | 26 | 28 | 39 | 53 | 66 | 77 |
| Level | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Unhealthy | Moderate | Moderate | Moderate | Poor | Poor | Unhealthy | Unhealthy |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 76 | Unhealthy |
| Feb | 71 | Unhealthy |
| Mar | 76 | Unhealthy |
| Apr | 98 | Unhealthy |
| May | 57 | Unhealthy |
| Jun | 32 | Moderate |
| Jul | 26 | Moderate |
| Aug | 28 | Moderate |
| Sep | 39 | Poor |
| Oct | 53 | Poor |
| Nov | 66 | Unhealthy |
| Dec | 77 | Unhealthy |
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.
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
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.