Verdict: Excellent month
Siem Reap Weather in December
December runs warm in Siem Reap, with daily highs around 30°C (86°F) and nights near 21°C (70°F). Rain is occasional — about 4 wet days in a typical year. Overall, December is one of the best months of the year to be in Siem Reap.
Average high
30°C / 86°F
Average low
21°C / 70°F
Rain days
~4
Precipitation
29 mm
What to pack for Siem Reap in December
- Light, breathable clothing — linen and technical fabrics earn their keep
- High-SPF sunscreen, sunglasses, and a refillable water bottle
- Comfortable walking shoes — every guide on this site assumes you'll use them
December 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)