December scores 86/100 for outdoor ceremonies: very low rain risk (2 wet days, 32mm), 20°C afternoons cooling to about 17°C for the reception, and 10.7 hours of daylight for the photography schedule. August is the month to avoid at 21/100.
December outdoor ceremony score: 86/100
Climate normals for Ha Long Bay rescored on wedding-specific weighting. Once your date falls inside the 14-day window the live forecast on this page takes over.
Last updated: · Live forecast data refreshes hourly.
| Best wedding month | December — 86/100 |
| Second choice | March — 80/100 |
| Month to avoid | August — 21/100 |
| Rain risk in the best month | Very low — rain on about 2 days |
| Guest comfort | 93/100 at 20°C |
| Reception temperature | ≈ 17°C after sunset in December |
| Photo light | 8h of sun across a 10.7h day |
| Months scoring 65+ | 6 of 12 |
December keeps seated guests at 20°C in the afternoon and around 17°C after sunset — the closest Ha Long Bay gets to a ceremony that needs neither shade structures nor patio heaters.
Rain falls on roughly 2 days in December (very low risk, 32mm). A simple marquee-on-standby is usually enough.
December gives 10.7 hours of daylight and about 8 hours of direct sun per day, so a late-afternoon ceremony puts portraits inside golden hour rather than after it.
August scores 21/100 for weddings in Ha Long Bay: 33°C highs, 310mm of rain and 28°C evenings make a fully outdoor plan fragile.
Scored on rain risk, guest comfort, evening temperature and photographic light — deliberately different weighting from the travel score.
| Month | Wedding score | Rain risk | Afternoon | Evening | Guest comfort | Photo light |
|---|---|---|---|---|---|---|
| January | 79/100 | Very low (2 days) | 18°C | 15°C | 86/100 | 50/100 |
| February | 79/100 | Very low (2 days) | 18°C | 15°C | 86/100 | 51/100 |
| March | 80/100 | Very low (3 days) | 20°C | 17°C | 93/100 | 49/100 |
| April | 71/100 | Low (6 days) | 24°C | 19°C | 92/100 | 47/100 |
| May | 40/100 | Moderate (13 days) | 27°C | 23°C | 79/100 | 25/100 |
| June | 31/100 | High (16 days) | 31°C | 26°C | 59/100 | 23/100 |
| July | 22/100 | High (19 days) | 33°C | 28°C | 47/100 | 0/100 |
| August | 21/100 | High (22 days) | 33°C | 28°C | 46/100 | 0/100 |
| September | 27/100 | High (17 days) | 31°C | 26°C | 57/100 | 2/100 |
| October | 39/100 | Moderate (12 days) | 27°C | 23°C | 79/100 | 11/100 |
| November | 76/100 | Low (5 days) | 24°C | 19°C | 92/100 | 68/100 |
| December | 86/100 | Very low (2 days) | 20°C | 17°C | 93/100 | 70/100 |
Wedding weather is scored differently from travel weather: seated guests in formalwear tolerate a narrower band than sightseers, and the ceremony hour matters more than the daily average. Each month in Ha Long Bay is scored 0–100 on the weighting below.
| Factor | Weight | What it measures |
|---|---|---|
| Dry conditions | 38% | Share of days with measurable rain — the single factor most likely to force a backup plan. |
| Guest comfort | 27% | Distance from a 22°C daytime ideal, with an extra penalty for humid heat above 24°C. |
| Evening temperature | 20% | Modelled reception-hour temperature against an 18°C ideal for an outdoor evening. |
| Photo light | 15% | Sunshine hours and daylight length, which set the length and quality of the golden hour window. |
Based on long-run climate averages rather than a forecast. Plan the ceremony around the golden hour — see golden hour times for Ha Long Bay linked below.
December, at 86/100. It combines very low rain risk with 20°C afternoons and roughly 17°C evenings, which is the most forgiving combination Ha Long Bay offers for seated guests.
August scores 21/100: 33°C highs, 310mm of rain over about 22 days and 28°C evenings make a fully outdoor plan fragile.
In December rain falls on roughly 2 of 30 days, so the single-day probability is about 7%. In August that rises to about 73%.
A marquee on standby is usually enough in December, where rain risk is very low. Outside the 6 months scoring 65 or higher, book real covered space.
December gives 10.7 hours of daylight and about 8 hours of direct sun. Put portraits in the final 60–90 minutes of daylight so they land inside golden hour rather than after it.