Rayong weather in December

In December, Rayong sees average daytime highs of 31°C and overnight lows near 23°C, with 17 mm of rain across 3.4 wet days and about 11.3 hours of daylight. It is the 8th-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 37% 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 Rayong's 4th-clearest and 4th-windiest month. For the whole year in context, see Rayong's year-round climate.

Daytime high
31°
8th warmest
Overnight low
23°
2nd coldest
Rainfall
17 mm
3.4 wet days
Daylight
11 h 18 min
6:33 AM – 5:49 PM
Cloud cover
53%
4th clearest
Wind
10 km/h
4th windiest
Solar energy
4.96 kWh/m²
Travel score
5.3
out of 10

Rayong is city in Rayong province, Thailand.

Air quality
Elevated
PM2.5 19.2 µg/m³ · 2019
Density
6,297/km²
people per km²
Founded
1917

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

Temperature in December

Average highAverage lowShaded bands: 10–90% of days

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

A typical December day in Rayong 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, December runs on par with November and on par with January.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13124
23124
33124
43124
53124
63123
73123
83123
93123
103123
113123
123123
133123
143123
153123
163123
173123
183123
193123
203123
213123
223123
233122
243122
253122
263122
273122
283122
293122
303122
313122

How December really feels in Rayong

Once humidity and wind are folded in, December averages 31 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
31
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

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

Rayong weather by month

How December compares with the rest of the year at a glance. December is the 8th-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°28611.35.1
Feb31° / 24°326.911.64.8
Mar32° / 25°8114.211.94.0
Apr32° / 26°1331912.33.1
May32° / 26°2202512.62.6
Jun31° / 26°21024.512.72.7
Jul31° / 26°2062512.72.8
Aug31° / 26°19624.912.42.8
Sep31° / 26°30126.412.12.6
Oct31° / 25°25623.211.73.1
Nov31° / 24°598.611.44.5
Dec31° / 23°173.411.35.3

Cloud cover in December

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in December.

Beyond those clear spells, partly cloudy skies cover about 22% of December, with mostly cloudy or overcast conditions the remaining 40%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
15644
25644
35644
45545
55644
65644
75644
85644
95743
105743
115743
125941
135941
146040
156040
166139
176139
186139
196238
206238
216238
226238
236337
246337
256337
266337
276337
286436
296436
306436
316436

Chance of precipitation in December

Any precipitation

Rayong gets around 17 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 18% on the wettest days. The odds ease toward the end of the month.

0%10%20%30%151015202531
Rain chance (%)
118
217
317
416
516
615
715
814
914
1013
1113
1212
1311
1411
1510
1610
179
189
199
209
218
228
238
247
257
267
277
288
298
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 31% 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 (%)
10315303319
20315313218
30416313117
40417323116
50417333016
60418333015
70518342914
80519342913
90519352912
101620342812
111620342811
121721342810
13172134289
14282233288
15282232288
16392231287
17392230287
183102329296
194102329296
204112328295
214112427295
225112427294
235112427294
245112427293
255112427293
265112428293
275112428302
285102428302
294102429312
30492429313
31492429323

Wind in December

Winds average 10 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
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
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 6:26 AM to 6:40 AM, and sunset from 5:44 PM to 5:56 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.36:265:44
211.36:265:44
311.36:275:44
411.36:275:45
511.36:285:45
611.36:285:45
711.36:295:46
811.36:295:46
911.36:305:46
1011.36:305:47
1111.36:315:47
1211.36:315:47
1311.36:325:48
1411.36:325:48
1511.36:335:48
1611.36:335:49
1711.36:345:49
1811.36:345:50
1911.36:355:50
2011.36:355:51
2111.36:365:51
2211.36:365:52
2311.36:375:52
2411.36:375:53
2511.36:385:53
2611.36:385:53
2711.36:395:54
2811.36:395:54
2911.36:395:55
3011.36:405:56
3111.36:405:56

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 4.49 kWh/m² to a high of 5.93 kWh/m² in April across the year — December's 4.96 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
14.9Bright
24.9Bright
34.9Bright
44.9Bright
54.9Bright
64.9Bright
74.9Bright
84.9Bright
94.9Bright
104.9Bright
114.9Bright
124.9Bright
134.9Bright
144.9Bright
154.9Bright
164.9Bright
175.0Bright
185.0Bright
195.0Bright
205.0Bright
215.0Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
285.0Bright
295.0Bright
305.0Bright
315.0Bright
Planning a trip in December

Hazard calendar for Rayong

In seasonPeak

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

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

Rayong'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 December a good time to visit Rayong?

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

5.3
Sightseeing
1st-best month of the year
7.7
Beach & pool
1st-best month of the year

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

What to pack for Rayong in December

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

In December, Rayong sees daytime highs around 31°C and nights near 23°C. Pack light clothes. Worth having: sun protection. About 3 days see rain.

light clothessun protection

Sea temperature near Rayong 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 14 km away) is warmest in May at about 31°C and coldest in January near 28°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
Jan28Warm
Feb28Tropical
Mar29Tropical
Apr30Tropical
May31Tropical
Jun30Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec28Tropical

UV index in Rayong 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 Rayong peaks around August 16 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 14 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 14Dec 14UV 9
UV index (midday)Level
Jan9Very high
Feb10Extreme
Mar12Extreme
Apr12Extreme
May12Extreme
Jun12Extreme
Jul12Extreme
Aug14Extreme
Sep12Extreme
Oct10Extreme
Nov9Very high
Dec9Very high

Air quality in Rayong 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 Rayong is worst in January — around 28 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (June, 12 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Rayong's WHO annual average of 19.2 µg/m³.

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateJan 2428 µg/m³Jun 2012 µg/m³
PM2.5 (µg/m³)Level
Jan28Moderate
Feb28Moderate
Mar21Moderate
Apr19Moderate
May15Moderate
Jun12Moderate
Jul13Moderate
Aug12Moderate
Sep15Moderate
Oct22Moderate
Nov22Moderate
Dec21Moderate
Location & terrain

Where is Rayong?

Rayong sits at 12.7°N, 101.3°E, 7 m above sea level, in Thailand. The nearest listed city is Ban Phe, 20 km away.

Topography around Rayong

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

Within 3 km, the terrain around Rayong has only modest variations in elevation — a maximum elevation change of 32 m around an average of 7 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 334 m; within 80 km, large variations in elevation — a maximum elevation change of 1,083 m.

The land around Rayong is covered by artificial surfaces (50%) and trees (25%) within 3 km, water (38%) and trees (35%) within 16 km, and water (47%) and trees (40%) within 80 km.

3 km
32 m
16 km
334 m
80 km
1,083 m
treesgrasslandcroplandartificial surfacesbare terrainwatermangroves
December weather nearby: Ban Phe 20 km · Ban Chang 23 km · Sattahip 39 km · Klaeng 44 km · Pattaya 49 km · Ban Talat Bueng 51 km · Bang Lamung 54 km · Si Racha 65 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 Rayong (12.6809°, 101.258°, elevation 7 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).