Rayong weather in January

In January, Rayong sees average daytime highs of 31°C and overnight lows near 23°C, with 28 mm of rain across 6 wet days and about 11.3 hours of daylight. It is the 7th-warmest and 11th-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 44% of the time in January, and the air most often feels oppressive.

Daylight stretches from about 11 h 18 min at the start of January to 11 h 24 min by month's end. Set against the rest of the year, January is Rayong's 2nd-clearest and 11th-windiest month. For the whole year in context, see Rayong's year-round climate.

Daytime high
31°
7th warmest
Overnight low
23°
1st coldest
Rainfall
28 mm
6 wet days
Daylight
11 h 18 min
6:44 AM – 6:04 PM
Cloud cover
47%
2nd clearest
Wind
8 km/h
11th windiest
Solar energy
5.1 kWh/m²
Travel score
5.1
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 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 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 29°C and 33°C. Set against its neighbours, January runs on par with December and on par with February.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
13122
23122
33123
43123
53123
63123
73123
83123
93123
103123
113123
123123
133123
143123
153123
163123
173123
183123
193123
203123
213123
223123
233123
243123
253123
263123
273123
283123
293123
303123
313123

How January really feels in Rayong

Once humidity and wind are folded in, January 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 January is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Rayong weather by month

How January compares with the rest of the year at a glance. January is the 7th-warmest and 11th-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 January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 44% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 22% of January, with mostly cloudy or overcast conditions the remaining 34%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16436
26436
36436
46436
56436
66436
76436
86436
96436
106436
116337
126337
136436
146436
156436
166337
176436
186436
196535
206535
216634
226733
236733
246931
256931
267030
277228
287228
297327
307426
317525

Chance of precipitation in January

Any precipitation

Rayong gets around 28 mm of rain over 6 wet days in January. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 19% and peaks near 22% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%151015202531
Rain chance (%)
110
211
312
413
513
614
715
816
917
1018
1119
1219
1320
1420
1521
1621
1721
1822
1922
2022
2122
2222
2322
2422
2521
2621
2721
2821
2920
3020
3120

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January lands in the oppressive band about 40% of days. Sticky, muggy-or-worse air turns up on roughly 73% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1482329323
2382329334
3372329334
4372329345
5372228356
6272227357
7272126367
8272125378
9272024389
102720233810
112719223910
122719214011
132719204011
142718204012
152718204112
162717204113
172717204213
182716204213
192716204213
202715204313
212615204313
222615204414
232614204414
242614204414
252614204414
262614204414
272614204514
282614194514
292614194514
302614184515
312614174615

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 9 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
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 18 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 6 minutes over January. Sunrise moves from 6:40 AM to 6:45 AM, and sunset from 5:56 PM to 6:11 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.36:405:56
211.36:415:57
311.36:415:57
411.36:415:58
511.36:425:58
611.36:425:59
711.36:425:59
811.36:436:00
911.36:436:00
1011.36:436:01
1111.36:436:01
1211.36:446:02
1311.36:446:03
1411.36:446:03
1511.36:446:04
1611.36:446:04
1711.36:456:05
1811.36:456:05
1911.36:456:06
2011.46:456:06
2111.46:456:07
2211.46:456:07
2311.46:456:08
2411.46:456:08
2511.46:456:09
2611.46:456:09
2711.46:456:10
2811.46:456:10
2911.46:456:11
3011.46:456:11
3111.46:456:11

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 5.1 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 — January's 5.1 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
105.0Bright
115.0Bright
125.0Bright
135.1Bright
145.1Bright
155.1Bright
165.1Bright
175.1Bright
185.1Bright
195.1Bright
205.1Bright
215.2Bright
225.2Bright
235.2Bright
245.2Bright
255.2Bright
265.2Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
315.3Bright
Planning a trip in January

Hazard calendar for Rayong

In seasonPeak

In January, 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 January a good time to visit Rayong?

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

5.1
Sightseeing
2nd-best month of the year
7.5
Beach & pool
2nd-best month of the year

January 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 January

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

In January, Rayong sees daytime highs around 31°C and nights near 23°C. Pack light clothes. Worth having: sun protection. About 6 days see rain.

light clothessun protection

Sea temperature near Rayong in January

The nearest coast averages about 28°C in January — 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 January

LowModerateHighVery highExtreme

Clear-sky midday UV in January 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 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 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
January 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).