Siem Reap weather in January

In January, Siem Reap sees average daytime highs of 31°C and overnight lows near 23°C, with 9 mm of rain across 1.9 wet days and about 11.3 hours of daylight. It is the 9th-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 51% of the time in January, and the air most often feels muggy.

Daylight stretches from about 11 h 12 min at the start of January to 11 h 24 min by month's end. Set against the rest of the year, January is Siem Reap's 2nd-clearest and 5th-windiest month. For the whole year in context, see Siem Reap's year-round climate.

Daytime high
31°
9th warmest
Overnight low
23°
2nd coldest
Rainfall
9 mm
1.9 wet days
Daylight
11 h 18 min
6:35 AM – 5:53 PM
Cloud cover
43%
2nd clearest
Wind
8 km/h
5th windiest
Solar energy
5.24 kWh/m²
Travel score
5.5
out of 10

Siem Reap is capital of the same named Cambodian province.

Founded
~802 CE

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 31°C through the month.

A typical January day in Siem Reap reaches about 31°C in the afternoon and slips back to 23°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 33°C. Set against its neighbours, January runs about 1°C warmer than December and about 2°C cooler than February.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13022
23122
33122
43122
53122
63123
73123
83123
93123
103123
113123
123123
133123
143123
153123
163123
173123
183123
193123
203123
213123
223123
233123
243123
253123
263123
273223
283223
293223
303223
313223

How January really feels in Siem Reap

Once humidity and wind are folded in, January averages 30 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in January is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Siem Reap weather by month

How January compares with the rest of the year at a glance. January is the 9th-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°91.911.35.5
Feb33° / 24°132.611.64.5
Mar34° / 26°527.811.93.2
Apr35° / 27°9413.512.32.5
May34° / 27°14821.412.62.2
Jun33° / 27°13220.712.82.4
Jul32° / 27°13522.112.72.6
Aug32° / 26°16224.412.42.4
Sep31° / 26°24425.912.12.5
Oct31° / 25°22423.311.73.1
Nov31° / 24°628.811.44.7
Dec30° / 23°162.911.25.7

Cloud cover in January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 51% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 17% of January, with mostly cloudy or overcast conditions the remaining 31%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16733
26733
36733
46733
56634
66733
76733
86733
96733
106634
116634
126634
136634
146634
156634
166634
176634
186733
196832
206832
216832
226931
237030
247030
257129
267228
277327
287327
297525
307624
317624

Chance of precipitation in January

Any precipitation

Siem Reap gets around 9 mm of rain over 1.9 wet days in January, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 6% and peaks near 7% on the wettest days.

0%10%20%30%151015202531
Rain chance (%)
15
25
35
45
55
65
76
86
96
106
116
126
136
146
156
166
176
186
197
207
217
227
237
247
257
267
277
287
296
306
316

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

Most of January feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, January lands in the muggy band about 37% of days. Sticky, muggy-or-worse air turns up on roughly 68% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1172639251
2172640251
3172541261
4172541261
5172441261
6172341262
7172341272
8172341272
9172240272
10182240273
11182239283
12182238283
13182238283
14182237293
15182237293
16192236293
17192236293
18192236293
19192236303
20192235303
21182235303
22182335303
23282334303
24282334303
25282334303
26282434303
27282433303
28292433303
29292432303
30292431303
31292531303

Wind in January

Winds average 8 km/h in January.

Across January, daily wind ranges from about 8 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm
318calm

Sunrise & sunset in January

DaylightNight

Daylight runs from about 11 h 12 min at the start of January to 11 h 24 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 12 minutes over January. Sunrise moves from 6:31 AM to 6:36 AM, and sunset from 5:44 PM to 6:00 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.26:315:44
211.26:315:45
311.26:325:46
411.26:325:46
511.26:325:47
611.26:335:47
711.26:335:48
811.26:335:48
911.36:345:49
1011.36:345:49
1111.36:345:50
1211.36:345:50
1311.36:355:51
1411.36:355:52
1511.36:355:52
1611.36:355:53
1711.36:355:53
1811.36:355:54
1911.36:365:54
2011.36:365:55
2111.36:365:55
2211.36:365:56
2311.36:365:56
2411.36:365:57
2511.46:365:57
2611.46:365:58
2711.46:365:58
2811.46:365:59
2911.46:365:59
3011.46:366:00
3111.46:366:00

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 5.24 kWh/m².

For context, solar energy here swings from a low near 4.62 kWh/m² to a high of 6.16 kWh/m² in April across the year — January's 5.24 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.1Bright
55.1Bright
65.1Bright
75.1Bright
85.1Bright
95.1Bright
105.1Bright
115.1Bright
125.2Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.2Bright
185.3Bright
195.3Bright
205.3Bright
215.3Bright
225.3Bright
235.4Bright
245.4Bright
255.4Bright
265.4Bright
275.5Bright
285.5Bright
295.5Bright
305.5Bright
315.5Bright
Planning a trip in January

Hazard calendar for Siem Reap

In seasonPeak

In January, Siem Reap sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Siem Reap sits in the Pacific typhoon belt; the season peaks July–October.

Siem Reap's rainy season runs May–October, when most of the year's rain falls.

Pacific typhoon
Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is January a good time to visit Siem Reap?

Our two travel scores rate January for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.5
Sightseeing
2nd-best month of the year
8.1
Beach & pool
1st-best month of the year

January is a reasonable time to visit Siem Reap for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Siem Reap in January

From January's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In January, Siem Reap sees daytime highs around 31°C and nights near 23°C. Pack light clothes. Worth having: sun protection.

light clothessun protection

UV index in Siem Reap in January

LowModerateHighVery highExtreme

Clear-sky midday UV in January peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Siem Reap peaks around August 16 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 22 at about 8 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highAug 16UV 14Nov 22UV 8
UV index (midday)Level
Jan10Very high
Feb10Very high
Mar12Extreme
Apr12Extreme
May11Extreme
Jun12Extreme
Jul13Extreme
Aug14Extreme
Sep12Extreme
Oct11Extreme
Nov8Very high
Dec8Very high

Air quality in Siem Reap in January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January falls, not just the annual average.

Air quality in Siem Reap is worst in February — around 40 µg/m³ PM2.5 (poor), about 2.9× the cleanest month (November, 14 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateFeb 2240 µg/m³Nov 2214 µg/m³
PM2.5 (µg/m³)Level
Jan29Moderate
Feb40Poor
Mar40Poor
Apr37Poor
May19Moderate
Jun15Moderate
Jul16Moderate
Aug15Moderate
Sep15Moderate
Oct17Moderate
Nov14Moderate
Dec14Moderate
Location & terrain

Where is Siem Reap?

Siem Reap sits at 13.4°N, 103.9°E, 18 m above sea level, in Cambodia. The nearest listed city is Yeang, 34 km away.

YeangPhum Ânlŭng VĭlBattambangPhumĭ TnaôtPursatSamraongSisophonAnlong Veaeng

Topography around Siem Reap

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Siem Reap.

Within 3 km, the terrain around Siem Reap has only modest variations in elevation — a maximum elevation change of 28 m around an average of 17 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 123 m; within 80 km, significant variations in elevation — a maximum elevation change of 484 m.

The land around Siem Reap is covered by artificial surfaces (60%) and trees (24%) within 3 km, cropland (45%) and trees (30%) within 16 km, and cropland (48%) and trees (30%) within 80 km.

3 km
28 m
16 km
123 m
80 km
484 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
January weather nearby: Yeang 34 km · Phum Ânlŭng Vĭl 74 km · Battambang 77 km · Phumĭ Tnaôt 89 km · Pursat 92 km · Samraong 98 km · Sisophon 99 km · Anlong Veaeng 100 km

Cambodia travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / C / G
230 V · 50 Hz
Prices
≈ 34% of US
price level, 2025
GDP per capita
$2,872
2025
Happiness
4.5 / 10
World Happiness, 2025
Safe drinking water
30%
of population, 2024
Homicide rate
1.8
per 100k, 2011
Road deaths
19.6
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Very low
EF EPI 390
Religion
Buddhist 97%Muslim 2%other 1%Christian 0%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Siem Reap (13.3618°, 103.8606°, elevation 18 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).