Weather in Siem Reap 🇰🇭
Monthly weather averages & travel planning
August
Avg Temp
31°C
Rain Days
25 days
Sun Hours
9 hrs
Humidity
82%
Asia › 🇰🇭 Cambodia › Siem Reap
Updated: March 2026
Is August a Good Time to Visit Siem Reap?
4/10
Fair
August is a fair time to visit Siem Reap (4/10). With 9 daily sunshine hours and only 25 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 11th sunniest of the year in Siem Reap. August suits travellers visiting for indoor culture, food, and architecture rather than outdoor activities. Pack accordingly for 25 potential rain days. September offers a similar profile at lower hotel rates if dates are flexible. Watch out for prolonged rain stretches: with 25 wet days, a fully outdoor itinerary is risky. Build in museum days and covered market visits as contingency. Planning tips: most accommodation categories have availability, and last-minute deals are common. The quieter streets and shorter queues can make this a genuinely enjoyable time to visit for the right type of traveller. Budget-conscious visitors will find the best value of the year in this period.
vs July:32°C avg high
The single most important thing to know about visiting Siem Reap in August: rain is a genuine factor across 25 days of the month, meaning your plans need built-in indoor alternatives. Precipitation totals 173mm for the month, spread across roughly 25 days, and 9 sunshine hours per day give you a reliable window for outdoor plans.
31°C
88°F
Avg High
25°C
77°F
Avg Low
25 days
173 mm total
Rain Days
9h
per day avg
Sunshine
82%
Humid
Humidity
Temperature in Siem Reap in August
The 6°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. At 82% humidity, the 31°C daytime high feels 2-4°C warmer in practice: quick-dry fabrics and shade-seeking between noon and 3pm are the sensible response. UV index averages 8 this month, classed as high to very high. SPF 30+ sunscreen, a brim hat, and sunglasses are not optional between 10am and 4pm. Wind averages 15 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 88°F average high, 77°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Temperature Trends
High
Low
Rainfall (mm)
0-20 mm21-50 mm51-100 mm100+ mm
What to Wear in Siem Reap in August
Morning25°CBefore the day warms up
Afternoon31°CPeak daytime temperature
Evening28°CAfter sunset cools down
Packing for Siem Reap in August means dressing for 31°C days and 25°C evenings. A lightweight linen or cotton shirt with loose-fit trousers or a sundress handles the 31°C daytime heat. Evening temperatures settle at 25°C, a modest 6°C drop that a light cardigan or denim jacket covers. For footwear, breathable walking sandals work for casual exploration, but closed-toe trainers are better for uneven surfaces in the historic centre. With 25 rain days expected, a compact travel umbrella is worth the bag space. A waterproof jacket is better than an umbrella if you plan full-day outdoor routes. For temple and religious site visits, carry a lightweight scarf or sarong to cover shoulders and knees, required at most major sites across the region. At 82% average humidity, quick-dry synthetic or bamboo fabrics dry overnight and stay comfortable longer than cotton.
Local tip: Loose-weave linen and moisture-wicking fabrics are the practical choice in Siem Reap's heat and humidity. Many shopping centres run air conditioning at near-arctic levels, so a thin layer in your bag prevents discomfort indoors.
Events in Siem Reap in August
August has no major festivals or public holidays in Siem Reap, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
What to Pack for Siem Reap in August
Based on 31°C average highs and 25 rainy days
- Lightweight breathable clothing
- Linen or bamboo shirts for the hottest hours
- Sun hat with a wide brim
- UV-protective sunglasses
- Hydration bottle (at least 1 litre)
- Quick-dry travel towel
- Anti-chafe balm for long walking days
- Moisture-wicking synthetic fabrics for active days
- Compact folding umbrella
- Waterproof outer layer or packable rain jacket
- Quick-dry clothing that recovers fast after a shower
- SPF 30+ sunscreen
- Comfortable walking shoes (a second pair lets the first air out overnight)
- Universal travel adapter
- Small day pack for city exploration
- Reusable water bottle
Best Activities in Siem Reap in August
- Early morning walk through Siem Reap's historic market districtBest before 9amTemperatures are still manageable at 27°C before the midday heat builds
- Open-air rooftop dining at sunsetFrom 6pm onwardsThe 31°C daytime heat drops noticeably after sunset, making al fresco dining comfortable
- Waterfront promenade or harbour walkEarly morning or after 5pmSea breezes cut through the humidity, making coastal routes the most pleasant in heat
- Guided cycling tour of the old quarterFirst tour of the day (7-9am)The low-traffic window before tourist crowds and the cooler morning air make this the prime riding slot
- Spend a morning in the national or city art museumOpens at 10am; arrive earlyWith 25 rain days expected, having a full-day indoor plan is practical insurance
- Cooking class focused on regional cuisineHalf-day sessions run 10am-1pm or 3-6pmIndoor activity that fills a rainy half-day with genuine cultural content
- Visit covered historical sites: cathedral, palace, or bazaarAny time; most crowded middayRoofed monuments and covered markets provide exploration without weather exposure
- Visit the main botanical garden or city park at seasonal peakYear-round; best light in morningAugust brings distinct seasonal changes to public green spaces worth exploring
- Seek out chilled local specialities: cold-brew tea, ice desserts, or chilled seafood at street-level stallsAny time; most atmospheric in evening marketsHot-weather street food culture peaks in August, with vendors setting up specifically for warm evenings
Why is Siem Reap warm in August?
Siem Reap's August climate is governed by the Inter-Tropical Convergence Zone (ITCZ), which draws moisture-laden trade winds across the region, producing the characteristic wet season rainfall of steamy tropical cities. Daytime heat peaks around 31°C, moderated slightly by afternoon convective showers. Overnight temperatures remain warm at 25°C because the humid air retains heat effectively. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Frequently Asked Questions
Siem Reap in August
In August, Siem Reap experiences average highs of 31°C (88°F) and lows of 25°C (77°F). Expect around 25 rainy days and 9 hours of sunshine per day, with humidity averaging 82%. The 6°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 8, so sun protection is advisable on clear days.
Siem Reap typically sees 25 rainy days in August, with total precipitation of around 173mm. This is a notably wet period. A waterproof jacket or compact umbrella is essential, and it is worth building indoor alternatives into your daily itinerary for the inevitable rainy stretches. For context, the driest month in Siem Reap typically sees 4-6 fewer rain days than August.
Pack lightweight, breathable clothing (linen or cotton), a wide-brim sun hat, SPF 50+ sunscreen, and a refillable water bottle for Siem Reap in August. The 31°C daytime heat demands sun protection during midday hours, typically 11am to 4pm. A compact travel umbrella is also worth packing, as 25 rainy days means afternoon showers are a real possibility. Quick-dry synthetic fabrics are preferable to cotton in 82% humidity.
August is a reasonable time to visit Siem Reap. Expect 25 rainy days, so pack a light rain layer for flexibility. Average temperatures of 31°C make outdoor exploration comfortable during the dry periods. With 9 daily sunshine hours, there are reliable windows of good weather to plan outdoor activities around, even if the month is not the driest on the calendar.
The average high temperature in Siem Reap in August is 31°C (88°F), and the average low is 25°C (77°F). The mean daily temperature is approximately 28°C (82°F). The day-to-night range of 6°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Siem Reap is generally January. January offers the most sunshine at 11 hours per day and only 2 rainy days. Average temperatures reach 31°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around January gives you the best chance of dry, bright weather.
August is shoulder or low season in Siem Reap, meaning fewer tourists and generally lower prices than peak months. With 9 sunshine hours and 25 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In August, Siem Reap suits a range of activities thanks to warm temperatures of 31°C. With frequent rain, indoor activities and covered attractions are a smart choice. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 9 hours of sunshine, parks and waterfront walks are particularly enjoyable.
August ranks 11th sunniest of the year in Siem Reap, with an average 9 daily sunshine hours. The driest months are January, February, and December. March is the hottest month (34°C avg high); September is the coolest (30°C). From here, temperatures fall 1°C into September. Compared to last month (July: 32°C high, 22 rain days), August is cooler and wetter. August is one of the least sunny months, but that often means lower prices and fewer fellow tourists.
Year-Round Climate
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 31°C | 21°C | 2 | 11h | View |
| February | 33°C | 23°C | 3 | 11h | View |
| March | 34°C | 25°C | 9 | 11h | View |
| April | 34°C | 26°C | 15 | 11h | View |
| May | 33°C | 26°C | 22 | 11h | View |
| June | 32°C | 26°C | 21 | 10h | View |
| July | 32°C | 25°C | 22 | 9h | View |
| August | 31°C | 25°C | 25 | 9h | View |
| September | 30°C | 25°C | 26 | 9h | View |
| October | 30°C | 24°C | 23 | 10h | View |
| November | 30°C | 23°C | 9 | 10h | View |
| December | 30°C | 21°C | 3 | 10h | View |
January
2 rain days, 11h sun
31°21°
February
3 rain days, 11h sun
33°23°
March
9 rain days, 11h sun
34°25°
April
15 rain days, 11h sun
34°26°
May
22 rain days, 11h sun
33°26°
June
21 rain days, 10h sun
32°26°
July
22 rain days, 9h sun
32°25°
August
25 rain days, 9h sun
31°25°
September
26 rain days, 9h sun
30°25°
October
23 rain days, 10h sun
30°24°
November
9 rain days, 10h sun
30°23°
December
3 rain days, 10h sun
30°21°
Other Months in Siem Reap
Plan Your Trip to Siem Reap
Nearby Destinations
Cities within 500 km with comparable weather conditions
Data Sources for Siem Reap
Climate normals represent 30-year averages (1991-2020). Individual years may vary.