Climate guide for Phong Nha, Vietnam

Phong Nha in May

Weather, crowds & best time to visit

How to read the score (0–10)
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May · Vietnam

Best time to visit Phong Nha in May Weather, crowds & prices

Weather in Phong Nha in May

Average temperature 26°C, 173 mm of rain, about 21 days with 6+ hours of sunshine and 86% humidity — based on the five most recent complete years of ERA5 data (2021–2025).

May score

4.7/10

Ranked #6 of 12 months

Full year for Phong Nha
Avg temp
26°C
Rainfall
173 mm
Humidity
86%
Days with 6h+ sun
21
Crowd Density
Quiet / Uncrowded
Average Expenses
$ · Budget Friendly ($)

May in Phong Nha scores 4.7/10 for nature and wildlife travel - an above-average month (#6 of 12). Expect around 26°C, 173 mm of rain, and roughly 21 days with 6+ hours of sunshine this month.

Phong Nha anchors the world's largest cave country with Son Doong expeditions and river cave boats. Best window: the drier months outside peak monsoon.

May in Phong Nha: expect compromises

May averages 26°C (79°F) and humidity near 86%, so the practical pattern is early mornings, a long midday break, and evenings back outside.

Monthly rainfall reaches 173 mm — wet for this destination — but about 21 days with 6+ hours of sunshine still break through, so keep one indoor fallback in the plan.

It scores 4.7/10 here, 6th of 12 months, against 7.3/10 in the destination's best month.

Pack the lightest breathable clothing you own, a hat, and more water than feels necessary, a proper rain shell rather than an umbrella, footwear you can get muddy.

Figure on low-season pricing, with crowds are light for this destination. That combination — decent conditions at the lowest rates of the year — is the best value window on this page.

Flexible dates? March scores 2.6 points higher here — enough to change the trip.

View all 12 months

Ranked by pure climate comfort

Score scale: 0.0 → 10.0Quiet / UncrowdedModerate CrowdsPeak Tourist Rush

Frequently asked

What is the weather like in Phong Nha in May?
In May, Phong Nha averages 26°C, 173 mm of rain, and about 21 days with 6+ hours of sunshine. Its climate-comfort score is 4.7/10.
Is May a good time to visit Phong Nha?
May earns a 4.7/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
How much does it rain in Phong Nha in May?
Expect about 173 mm of rain in May. Average humidity is 86% and there are about 21 days with 6+ hours of sunshine.

Curated in Phong Nha

Tickets & experiences

Things to do in Phong Nha

Phong Nha, Vietnam. Live activities and tours from GetYourGuide, matched to this destination.