On the cooler side.
December in context
How it compares to the rest of the year in Hanoi.
One of the drier months.
Shorter days.
Close to the yearly wind average.
UV is gentler than usual.
One of the less humid months.
Monthly climate breakdown
A detailed look at the typical climate conditions for December.
Thermal profile
Temperature
Typical daytime high
- Nighttime low
-
- Feels like (avg)
-
Light window
Sunshine
10.9 h
Average daylight
- UV index (max)
- 6
- Typical sun hours
- 06:25 - 17:18
Wet-day pattern
Rain & Snow
Typical rainfall
- Rainy days
- 9 days
- Cloud cover (avg)
- 65%
Air feel
Humidity & Wind
72%
Average humidity
- Wind (avg)
-
- Wind (max gusts)
-
Historical daily baseline
Daily climate explorer
Pick a day to inspect the usual conditions through December in Hanoi. Based on a 30-year historical climate baseline, not a forecast.
Primary control
Select a day
Scroll to compare daily conditions. The summary updates with your selection.
Secondary context
Monthly trend
Median daytime highs across the month, with a softer low line.
Day 15 selected for December. Temperature 20.6°C.
Historical disruption baseline
Typical disruptions in December
Based on 30 years of historical data, these are the disruption patterns most likely to affect plans in December.
Washout risk Measures: Washout day risk. Observed about 6% of days (1.9 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.9 days / month
- Share of days
- ~6% of days
- Upper edge
- Up to ~23mm (P95)
Why this matters
Washout conditions are possible on ~2 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Rain disruption Measures: Likely rain disruption days. Observed about 6% of days (2.0 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
2.0 days / month
- Share of days
- ~6% of days
- Upper edge
- Up to ~23mm (P95)
Why this matters
Rain disruption risk appears on ~2 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Muggy days Measures: Muggy days (dew point >=20C). Observed about 5% of days (1.5 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.5 days / month
- Share of days
- ~5% of days
- Upper edge
- Up to ~23°C (P95)
Why this matters
Muggy conditions are possible on ~1 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Cold feels-like nights Measures: Cold feels-like nights (min <=5C). Observed about 3% of days (1.1 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.1 days / month
- Share of days
- ~3% of days
- Upper edge
- Up to ~5°C (P95)
Why this matters
Cold feels-like nights are possible on ~1 days. Long outdoor blocks become harder to sustain, so layer up and keep a warm indoor fallback nearby.
Show all disruptions (16 more)
Washout run Measures: Multi-day washout runs. Observed about 0.5 days/month in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.5 days / month
- Share of days
- —
- Upper edge
- Up to ~32mm (P95)
Why this matters
Multi-day washout runs are possible on ~0 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Heavy rain days Measures: Heavy rain days (>=10mm). Observed about 2% of days (0.8 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.8 days / month
- Share of days
- ~2% of days
- Upper edge
- Up to ~26mm (P95)
Why this matters
Heavy rain is possible on ~1 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Hot feels-like days Measures: Hot feels-like days (>=32C). Observed about 1% of days (0.3 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.3 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~34°C (P95)
Why this matters
Feels-like heat >=32C is possible on ~0 days. Midday activity often needs adjustment around shade, hydration, and indoor fallback options.
Cloudy days Measures: Cloudy days (cloud cover >=60%). Observed about 62% of days (19.1 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
19.1 days / month
- Share of days
- ~62% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Cloudy skies are possible on ~19 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Mostly cloudy days Measures: Mostly cloudy days (cloud cover >=80%). Observed about 43% of days (13.4 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
13.4 days / month
- Share of days
- ~43% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Mostly cloudy skies are possible on ~13 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wet days Measures: Wet days (>=0.1mm). Observed about 39% of days (12.0 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
12.0 days / month
- Share of days
- ~39% of days
- Upper edge
- Up to ~11mm (P95)
Why this matters
Measurable rain is possible on ~12 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
High humidity Measures: High humidity days (RH >=80%). Observed about 33% of days (10.2 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
10.2 days / month
- Share of days
- ~33% of days
- Upper edge
- Up to ~90% (P95)
Why this matters
High humidity is possible on ~10 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Rainy hours Measures: Rain-hours signal (>=3h rain). Observed about 28% of days (8.8 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
8.8 days / month
- Share of days
- ~28% of days
- Upper edge
- Up to ~21h (P95)
Why this matters
Several rainy hours are possible on ~9 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Overcast days Measures: Overcast days (cloud cover >=95%). Observed about 25% of days (7.6 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
7.6 days / month
- Share of days
- ~25% of days
- Upper edge
- Up to ~100% (P95)
Why this matters
Overcast skies are possible on ~8 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Wet most of day Measures: Wet-most-of-day signal (>=6h rain). Observed about 18% of days (5.6 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
5.6 days / month
- Share of days
- ~18% of days
- Upper edge
- Up to ~22h (P95)
Why this matters
Wet-most-of-day conditions are possible on ~6 days. Outdoor plans can become unreliable, so keep an indoor backup and flexibility around start times.
Humid days Measures: Humid days (dew point >=18C). Observed about 13% of days (3.9 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
3.9 days / month
- Share of days
- ~13% of days
- Upper edge
- Up to ~22°C (P95)
Why this matters
Humid conditions are possible on ~4 days. Comfort and pace can drop quickly, so plan shorter outdoor blocks with air-conditioned backup stops.
Gusty days Measures: Gusty days (>=40 km/h). Observed about 4% of days (1.2 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
1.2 days / month
- Share of days
- ~4% of days
- Upper edge
- Up to ~52km/h (P95)
Why this matters
Gusty conditions are possible on ~1 days. Exposed activities and transport links are more likely to be disrupted, so keep sheltered alternatives ready.
Warm nights Measures: Warm nights (min >=22C). Observed about 1% of days (0.5 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.5 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~23°C (P95)
Why this matters
Warm nights are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Fog-likely signal Measures: Fog-likely visibility proxy. Observed about 1% of days (0.4 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~92% (P95)
Why this matters
Fog-likely conditions are possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data Measures: Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data. Observed about 1% of days (0.4 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~92 (P95)
Why this matters
Low visibility proxy: same as fog-likely (RH ≥90% AND cloud ≥95%) — true visibility requires hourly visibility data is possible on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Convective risk Measures: Convective storm risk proxy. Observed about 1% of days (0.4 days/month) in December. Historical risk signal only, not a day-by-day forecast.
Likely frequency
0.4 days / month
- Share of days
- ~1% of days
- Upper edge
- Up to ~22°C (P95)
Why this matters
Convective risk signal appears on ~0 days. Fixed-time outdoor plans are safer with a backup option and flexible timing.
Travel planning FAQ
Frequently asked questions
Quick answers to the weather questions you ask the most.
Is December a good time to visit Hanoi?
Typical December days in Hanoi reach highs of 21°C (70°F) with nights around 14°C (57°F). It usually feels mild by day and cool after dark. It is one of the drier months, which suits outdoor exploring and sightseeing.
What are temperatures like in December?
In December, you can usually expect highs of 21°C (70°F) and lows near 14°C (57°F). That means mild days and cool nights, so pack layers you can add or remove.
How much does it rain in December?
Rainfall in December averages 33 mm (1.3 in) across roughly 9 days. Overall it is a moderately wet time of year, so showers are usually brief rather than all-day downpours.
How many hours of daylight are there in December?
You can expect about 11 hours of daylight in December. Sunrise is typically around 06:25 and sunset near 17:18. Days are on the shorter side, so plan activities around limited daylight.
How strong is the sun in December?
UV levels are moderate (around 6); sunscreen and sunglasses are still a good idea.
Is it windy in December?
In December, average wind speeds are around 8 km/h (5 mph), with gusts on the windiest days reaching about 34 km/h (21 mph). On the ground, it is a gentle to moderate breeze is common, but stronger winds are not frequent.