Cambodia Siem Reap Weather in December — Climate Guide
December in Siem Reap is very-high
December is very-high for Siem Reap.
December is the cool dry peak returning — 31°C / 88°F highs, 21°C / 70°F dawns, just 2 rainy days, 15mm rainfall. Conditions return to January-February levels.
December 1-15 is the year's last value window — same peak conditions at 80% of December 22-January 5 pricing. December 22-January 5 is the year's most expensive period: Raffles $800-1,500/night, Park Hyatt $500-900.
Travel score
Cool dry peak + Christmas-New Year — perfect conditions + maximum pricing
December Weather at a Glance
December averages 31°C / 88°F highs and 21°C / 70°F dawns with only 2 rainy days and 15mm rainfall. Humidity 60%, UV 9. Sunrise 6:20 AM, sunset 5:40 PM. Perfect dry-season conditions identical to January.
December Travel Advice
Book December 22-January 5 hotels 2-3 months ahead — Raffles + Park Hyatt + Belmond all sell out. December 1-15 is the year's last value window. December 31 countdown packages at 5-stars require 2-3 month booking.
Flying In from Overseas
Year's peak — Korean + European + Australian + Russian tourists converge. Direct flights from Bangkok $50-120, Singapore $200-400. Korean Lunar New Year approaches.
December Pricing Trends
Peak season: Raffles $500-1,500/night (Dec 22-Jan 5), Park Hyatt $400-900, FCC Angkor $200-450, Onederz Hostel $15-35. Cuisine Wat Damnak countdown tasting $80-120.
Siem Reap December Weather Stats
Avg High
31°C
Avg Low
21°C
Rainy Days
2
15mm total
Sunshine
9h
Daily avg
Humidity
60%
moderate
UV Index
9
Very high
Wind
8 km/h
Gusts 18
Sea Temp
0°C
no swimming
Crowds
Very busy
At attractions
December Sunrise & Sunset
Air Quality
PM2.5
32 μg/m³
PM10
52 μg/m³
Status
moderate
Feels-Like Temperature & Wind
Feels like
Daytime
33°C
Nighttime
22°C
Humidity and wind affect how the actual temperature feels.
Wind
8 km/h
Max gust 18 km/h
Activities Recommended for December
December Travel Pros & Cons
Pros
- Cool dry perfect Angkor conditions
- Christmas-New Year atmosphere
- December 31 countdown at 5-stars + Pub Street
- December 1-15 last value window
Cons
- December 22-January 5 year's highest pricing (hotels +100%)
- Tourist crush at Angkor Wat sunrise (300+)
- 3-month-ahead booking required for peak week
December Events & Festivals
- Cool dry peak season returns
- Christmas-New Year peak — Korean + European tourists
- December 31 countdown parties at Pub Street + 5-star hotels
Siem Reap in December — Full Picture
December is the cool dry peak returning — 31°C / 88°F highs, 21°C / 70°F dawns, just 2 rainy days, 15mm rainfall. Conditions return to January-February levels.
December 1-15 is the year's last value window — same peak conditions at 80% of December 22-January 5 pricing. December 22-January 5 is the year's most expensive period: Raffles $800-1,500/night, Park Hyatt $500-900.
December 31 countdown: Raffles Grand + Park Hyatt + Belmond + Pub Street all run countdown packages with dinners + fireworks + champagne. Book 2-3 months ahead. The single best night for honeymoon + anniversary travelers seeking Cambodia luxury experience.
What to Wear & What to Pack
Cool dry — light tropical day + light jacket for cool 21°C dawns (Angkor sunrise). Modest temple cover-up. SPF 50+.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
35.7°C
24.3°C
6.7/mo
Summer (Jun·Jul·Aug)
33.3°C
25°C
15/mo
Autumn (Sep·Oct·Nov)
31.7°C
23.3°C
13.7/mo
Winter (Dec·Jan·Feb)
Current32°C
21°C
1.3/mo
Siem Reap Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| January (Best) | 32° | 21° | 1d·10mm | 9h | 60% | 10 | Very busy | Peak |
| February (Best) | 33° | 21° | 1d·5mm | 10h | 55% | 10 | Very busy | Peak |
| March (Best) | 35° | 23° | 3d·25mm | 9h | 55% | 11 | Busy | Shoulder |
| 37° | 25° | 4d·50mm | 9h | 60% | 11 | Moderate | Shoulder | |
| 35° | 25° | 13d·175mm | 7h | 75% | 11 | Quiet | Low season | |
| 34° | 25° | 14d·175mm | 6h | 80% | 11 | Moderate | Low season | |
| 33° | 25° | 15d·200mm | 6h | 80% | 10 | Moderate | Shoulder | |
| 33° | 25° | 16d·225mm | 6h | 80% | 10 | Moderate | Shoulder | |
| 32° | 24° | 18d·275mm | 5h | 85% | 10 | Quiet | Low season | |
| 32° | 24° | 16d·230mm | 6h | 80% | 9 | Moderate | Low season | |
| November (Best) | 31° | 22° | 7d·70mm | 7h | 70% | 9 | Busy | Shoulder |
| December (Best) | 31° | 21° | 2d·15mm | 9h | 60% | 9 | Very busy | Peak |
View Other Months
Siem Reap December Hotel Picks
Frequently Asked Questions
Is December a good time to visit Siem Reap?
Siem Reap in December is very-high. Tourist crowds are very busy and flight/hotel prices are peak.
What's the average temperature in Siem Reap in December?
Siem Reap December averages a high of 31°C and a low of 21°C.
Does it rain much in Siem Reap in December?
Siem Reap December averages 15mm of rainfall over about 2 rainy days.
What should I wear in Siem Reap in December?
Cool dry — light tropical day + light jacket for cool 21°C dawns (Angkor sunrise). Modest temple cover-up. SPF 50+.
What time are sunrise and sunset in Siem Reap in December?
Siem Reap December sunrise is 06:20 and sunset is 17:40, with 11h 20min of daylight.
What's the air quality like in Siem Reap in December?
Siem Reap December air quality (AQI) averages 75, rated Moderate. PM2.5 averages 32μg/m³.
What activities are recommended in Siem Reap in December?
In December, Siem Reap is great for Angkor Wat sunrise, Bayon Temple, Ta Prohm.
Is December peak season in Siem Reap?
Siem Reap December crowds are very busy and prices are peak. Advance reservations are strongly recommended.
Best Months to Visit Siem Reap
View Other Months
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.