The short answer
When to go to Phong Nha
February to April is the best window: highs run roughly 22 to 29 degrees with the least rain of the year, and the caves and river are at their most accessible. May to August is hot, with highs above 30 degrees, but still workable early in the day. September to November brings the heaviest rain, with October alone averaging around 650 mm, so caves can close and roads can flood. Older travellers will find February to April kindest.
Month by month
Phong Nha weather by month
| Month | High | Low | Rain | Verdict | What to expect |
|---|---|---|---|---|---|
| January | 22°C | 17°C | 59 mm | Mild and damp; some drizzle, cool in the caves | |
| February | 22°C | 18°C | 40 mm | Mild and among the driest months | |
| March | 25°C | 20°C | 43 mm | Warm, dry and comfortable for caves | |
| April | 29°C | 22°C | 61 mm | Warm and still relatively dry | |
| May | 32°C | 25°C | 116 mm | Hot; start early and rest in the afternoon | |
| June | 34°C | 27°C | 79 mm | Hot and humid; short outings only | |
| July | 34°C | 27°C | 76 mm | Hot and humid; plan around the midday heat | |
| August | 33°C | 26°C | 166 mm | Hot, rain increases late in the month | |
| September | 31°C | 24°C | 473 mm | Heavy rain; caves and tours may close | |
| October | 28°C | 23°C | 649 mm | Wettest month; flooding and closures likely | |
| November | 26°C | 20°C | 319 mm | Still very wet; check cave access first | |
| December | 23°C | 18°C | 125 mm | Cooler and drying, but showers continue |
Temperatures and rainfall are long-term monthly averages. Check the forecast a few days before you travel.
Seasons at a glance
Phong Nha seasons for families and seniors
The easiest months: February, March and April
- February: Mild and among the driest months
- March: Warm, dry and comfortable for caves
- April: Warm and still relatively dry
Good, with small trade-offs: January and May
- January: Mild and damp; some drizzle, cool in the caves
- May: Hot; start early and rest in the afternoon
Possible, with planning: June, July, August and December
- June: Hot and humid; short outings only
- July: Hot and humid; plan around the midday heat
- August: Hot, rain increases late in the month
- December: Cooler and drying, but showers continue
Best avoided with parents or children: September, October and November
- September: Heavy rain; caves and tours may close
- October: Wettest month; flooding and closures likely
- November: Still very wet; check cave access first
Useful answers
Best time to visit Phong Nha: FAQs
What is the best month to visit Phong Nha?
February, March and April are the best months to visit Phong Nha, with January and May also good. February to April is the best window: highs run roughly 22 to 29 degrees with the least rain of the year, and the caves and river are at their most accessible. May to August is hot, with highs above 30 degrees, but still workable early in the day. September to November brings the heaviest rain, with October alone averaging around 650 mm, so caves can close and roads can flood. Older travellers will find February to April kindest.
Which months should I avoid in Phong Nha with elderly parents?
September, October and November are the months to avoid with older travellers. Heavy rain; caves and tours may close Wettest month; flooding and closures likely
When does it rain most in Phong Nha?
October is the wettest month, with about 649 mm of rain on average. The hottest month is June, with average highs around 34°C.