Verdict: Tough month
Siem Reap Weather in May
May is seriously hot in Siem Reap — days average 33°C (91°F), so plan mornings out and afternoons in the shade or the water. It's also the wet side of the calendar: rain falls on about 23 days, so build flexibility into plans. If your dates are flexible, most travelers will have a better time in Siem Reap outside May.
Average high
33°C / 91°F
Average low
26°C / 79°F
Rain days
~23
Precipitation
227 mm
What to pack for Siem Reap in May
- Light, breathable clothing — linen and technical fabrics earn their keep
- High-SPF sunscreen, sunglasses, and a refillable water bottle
- Rain gear is non-negotiable — expect rain on roughly 23 days
- Comfortable walking shoes — every guide on this site assumes you'll use them
May against the rest of the year
Warmest in Siem Reap: Mar (35°C / 95°F) · Coolest: Oct (30°C / 86°F) · Wettest: Sep (~29 rain days)
31°
21°
Jan
33°
23°
Feb
35°
25°
Mar
34°
26°
Apr
33°
26°
May
33°
26°
Jun
32°
25°
Jul
32°
25°
Aug
31°
24°
Sep
30°
23°
Oct
30°
23°
Nov
30°
21°
Dec
Daily highs / lows in °C · bars show rain days per month · ERA5 climate normals (2020–2024)