Sam Roi Yot weather in December

In December, Sam Roi Yot sees average daytime highs of 29°C and overnight lows near 21°C, with 16 mm of rain across 3.4 wet days and about 11.3 hours of daylight. It is the 12th-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 43% of the time in December, and the air most often feels muggy.

Daylight stretches from about 11 h 18 min at the start of December to 11 h 18 min by month's end. Set against the rest of the year, December is Sam Roi Yot's 4th-clearest and 4th-windiest month. For the whole year in context, see Sam Roi Yot's year-round climate.

Daytime high
29°
12th warmest
Overnight low
21°
2nd coldest
Rainfall
16 mm
3.4 wet days
Daylight
11 h 18 min
6:38 AM – 5:55 PM
Cloud cover
50%
4th clearest
Wind
9 km/h
4th windiest
Solar energy
4.96 kWh/m²
Travel score
6.2
out of 10

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 29°C through the month.

A typical December day in Sam Roi Yot reaches about 29°C in the afternoon and slips back to 21°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 32°C. Set against its neighbours, December runs on par with November and about 1°C cooler than January.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13022
23022
32922
42922
52922
62922
72922
82922
92922
102922
112922
122922
132922
142922
152922
162921
172921
182921
192921
202921
212921
222921
232921
242921
252921
262921
272921
282921
292921
302921
313021

How December really feels in Sam Roi Yot

Once humidity and wind are folded in, December averages 0 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
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

December sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Sam Roi Yot weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 21°294.711.45.7
Feb32° / 22°184.611.64.8
Mar33° / 23°6810.711.93.5
Apr34° / 25°961712.32.5
May33° / 25°18025.412.62.1
Jun32° / 25°14323.312.72.6
Jul31° / 24°17924.512.62.8
Aug31° / 24°18224.712.42.8
Sep31° / 24°23026.112.12.6
Oct30° / 23°23224.811.73.3
Nov30° / 23°629.711.45.2
Dec29° / 21°163.411.36.2

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 20% of December, with mostly cloudy or overcast conditions the remaining 38%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15842
25941
35941
46040
56139
66139
76139
86040
96040
106040
116139
126139
136238
146238
156337
166238
176238
186337
196337
206436
216436
226436
236436
246436
256535
266535
276535
286535
296535
306535
316535

Chance of precipitation in December

Any precipitation

Sam Roi Yot gets around 16 mm of rain over 3.4 wet days in December, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 11% and peaks near 20% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202531
Rain chance (%)
120
219
319
418
517
617
716
815
914
1014
1113
1212
1311
1410
159
169
179
188
198
208
218
228
237
247
257
268
278
288
299
309
3110

Humidity in December

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, December lands in the muggy band about 35% of days. Sticky, muggy-or-worse air turns up on roughly 64% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1041632462
2051733442
3051733431
4051735421
5061835401
6061836381
7071937371
8071937361
9071938341
10082038330
11082139320
12192139310
131102238290
141102238280
152112337270
162122337270
172122336260
183132435250
193142434240
204142533230
214152633230
225152632220
235152732210
245152732200
255162733190
265162833180
275152834170
285152835170
295152836170
305142836170
315132837170

Wind in December

Winds average 9 km/h in December.

Across December, daily wind ranges from about 9 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
1810calm
1910calm
2010calm
219calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

Sunrise & sunset in December

DaylightNight

Daylight runs from about 11 h 18 min at the start of December to 11 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 0 minutes over December. Sunrise moves from 6:30 AM to 6:45 AM, and sunset from 5:50 PM to 6:02 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.36:305:50
211.36:315:50
311.36:315:51
411.36:325:51
511.36:325:51
611.36:335:52
711.36:345:52
811.36:345:52
911.36:355:52
1011.36:355:53
1111.36:365:53
1211.36:365:54
1311.36:375:54
1411.36:375:54
1511.36:385:55
1611.36:385:55
1711.36:395:56
1811.36:395:56
1911.36:405:56
2011.36:405:57
2111.36:415:57
2211.36:415:58
2311.36:425:58
2411.36:425:59
2511.36:435:59
2611.36:436:00
2711.36:436:00
2811.36:446:01
2911.36:446:01
3011.36:456:02
3111.36:456:02

Solar energy in December

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in December, about 4.96 kWh/m².

For context, solar energy here swings from a low near 4.19 kWh/m² to a high of 6.11 kWh/m² in April across the year — December's 4.96 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
14.8Bright
24.8Bright
34.8Bright
44.8Bright
54.8Bright
64.8Bright
74.8Bright
84.8Bright
94.8Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
144.9Bright
155.0Bright
165.0Bright
175.0Bright
185.0Bright
195.0Bright
205.0Bright
215.0Bright
225.1Bright
235.1Bright
245.1Bright
255.1Bright
265.1Bright
275.1Bright
285.1Bright
295.1Bright
305.1Bright
315.1Bright
Planning a trip in December

Hazard calendar for Sam Roi Yot

In seasonPeak

In December, Sam Roi Yot sits inside its cyclone season. The full year is below, with each hazard's peak months called out.

Sam Roi Yot sits in the North Indian Ocean cyclone zone; the season peaks May and October–November.

Sam Roi Yot's rainy season runs May–October, when most of the year's rain falls.

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

Is December a good time to visit Sam Roi Yot?

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

6.2
Sightseeing
1st-best month of the year
8.1
Beach & pool
1st-best month of the year

December is a reasonable time to visit Sam Roi Yot for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Sam Roi Yot in December

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

In December, Sam Roi Yot sees daytime highs around 29°C and nights near 21°C. Pack light clothes. Worth having: sun protection. About 3 days see rain.

light clothessun protection

Sea temperature near Sam Roi Yot in December

The nearest coast averages about 28°C in December — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 30 km away) is warmest in May at about 30°C and coldest in January near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb28Warm
Mar29Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul30Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec28Warm

UV index in Sam Roi Yot in December

LowModerateHighVery highExtreme

Clear-sky midday UV in December peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sam Roi Yot peaks around August 16 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 23 at about 9 (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 23UV 9
UV index (midday)Level
Jan9Very high
Feb10Extreme
Mar12Extreme
Apr12Extreme
May12Extreme
Jun12Extreme
Jul12Extreme
Aug14Extreme
Sep12Extreme
Oct11Extreme
Nov9Very high
Dec9Very high

Air quality in Sam Roi Yot in December

GoodModeratePoorUnhealthyVery unhealthy

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

Air quality in Sam Roi Yot is worst in April — around 26 µg/m³ PM2.5 (moderate), about 2.4× the cleanest month (September, 11 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateApr 1025 µg/m³Sep 1211 µg/m³
PM2.5 (µg/m³)Level
Jan24Moderate
Feb24Moderate
Mar25Moderate
Apr26Moderate
May16Moderate
Jun12Moderate
Jul13Moderate
Aug12Good
Sep11Good
Oct14Moderate
Nov19Moderate
Dec20Moderate
Location & terrain

Where is Sam Roi Yot?

Sam Roi Yot sits at 12.3°N, 99.9°E, 17 m above sea level, in Thailand. The nearest listed city is Pran Buri, 13 km away.

PhetchaburiKhao Yoi

Topography around Sam Roi Yot

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Sam Roi Yot.

Within 3 km, the terrain around Sam Roi Yot has only modest variations in elevation — a maximum elevation change of 144 m around an average of 12 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 573 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,303 m.

The land around Sam Roi Yot is covered by trees (47%) and grassland (29%) within 3 km, trees (57%) within 16 km, and trees (56%) and water (35%) within 80 km.

3 km
144 m
16 km
573 m
80 km
1,303 m
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
December weather nearby: Pran Buri 13 km · Kui Buri 21 km · Hua Hin 35 km · Prachuap Khiri Khan 51 km · Cha-am 60 km · Tha Yang 76 km · Phetchaburi 94 km · Khao Yoi 108 km

Thailand travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B / C
230 V · 50 Hz
Prices
≈ 31% of US
price level, 2025
GDP per capita
$8,057
2025
Happiness
6.3 / 10
World Happiness, 2025
Homicide rate
4.8
per 100k, 2011
Road deaths
32.2
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 402
Religion
Buddhist 93%Muslim 5%Christian 1%other 1%

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 Sam Roi Yot (12.2708°, 99.872°, elevation 17 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). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. 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).