Sam Roi Yot weather in May

In May, Sam Roi Yot sees average daytime highs of 33°C and overnight lows near 25°C, with 180 mm of rain across 25.4 wet days and about 12.6 hours of daylight. It is the 2nd-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 33°C through the month. The sky is clear or mostly clear about 5% of the time in May, and the air most often feels oppressive.

Daylight stretches from about 12 h 24 min at the start of May to 12 h 42 min by month's end. Set against the rest of the year, May is Sam Roi Yot's 8th-clearest and 7th-windiest month. For the whole year in context, see Sam Roi Yot's year-round climate.

Daytime high
33°
2nd warmest
Overnight low
25°
12th coldest
Rainfall
180 mm
25.4 wet days
Daylight
12 h 36 min
6:00 AM – 6:34 PM
Cloud cover
82%
8th clearest
Wind
8 km/h
7th windiest
Solar energy
5.28 kWh/m²
Travel score
2.1
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 33°C through the month.

A typical May day in Sam Roi Yot reaches about 33°C in the afternoon and slips back to 25°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 30°C and 36°C. Set against its neighbours, May runs about 1°C cooler than April and about 1°C warmer than June.

20°25°30°35°40°151015202531
Avg high (°C)Avg low (°C)
13425
23425
33425
43425
53425
63425
73425
83425
93325
103325
113325
123325
133325
143325
153325
163325
173325
183325
193325
203325
213325
223325
233325
243325
253325
263325
273325
283325
293325
303225
313225

How May really feels in Sam Roi Yot

Once humidity and wind are folded in, May 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
11 feel dangerously hot (≥ 39°C)
Days feeling ≤ C
0
wind chill below the day's low

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

Sam Roi Yot weather by month

How May compares with the rest of the year at a glance. May is the 2nd-warmest and 4th-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 May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 5% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 11% of May, with mostly cloudy or overcast conditions the remaining 84%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13565
23367
33268
43070
52872
62773
72674
82377
92278
102179
112080
121882
131783
141585
151585
161486
171288
181288
191189
201090
21991
22991
23892
24892
25793
26793
27694
28694
29694
30694
31694

Chance of precipitation in May

Any precipitation

Sam Roi Yot gets around 180 mm of rain over 25.4 wet days in May. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 82% and peaks near 87% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
172
273
374
475
576
677
778
879
980
1080
1181
1281
1382
1482
1583
1683
1783
1883
1984
2084
2184
2285
2385
2485
2585
2686
2786
2886
2986
3087
3187

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the oppressive band about 71% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
117326
217227
317128
417029
516930
616930
716831
806931
906931
1006931
1106931
1207030
1307030
1407129
1507129
1607228
1707327
1807327
1907327
2007327
2107327
2207327
2307327
2407327
2507228
2607228
2707228
2807129
2907129
3007030
3107030

Wind in May

Winds average 8 km/h in May.

Across May, daily wind ranges from about 7 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
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
209calm
219calm
229calm
239calm
249calm
259calm
269calm
279calm
289calm
299calm
309calm
319calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 24 min at the start of May to 12 h 42 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over May. Sunrise moves from 6:05 AM to 5:58 AM, and sunset from 6:31 PM to 6:38 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.46:056:31
212.46:046:31
312.46:046:31
412.56:046:31
512.56:036:31
612.56:036:31
712.56:026:32
812.56:026:32
912.56:026:32
1012.56:016:32
1112.56:016:33
1212.56:016:33
1312.56:016:33
1412.56:006:33
1512.66:006:33
1612.66:006:34
1712.66:006:34
1812.65:596:34
1912.65:596:34
2012.65:596:35
2112.65:596:35
2212.65:596:35
2312.65:596:35
2412.65:586:36
2512.65:586:36
2612.65:586:36
2712.65:586:37
2812.65:586:37
2912.75:586:37
3012.75:586:37
3112.75:586:38

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.28 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 — May's 5.28 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.8Bright
25.7Bright
35.7Bright
45.7Bright
55.6Bright
65.6Bright
75.5Bright
85.5Bright
95.5Bright
105.4Bright
115.4Bright
125.4Bright
135.3Bright
145.3Bright
155.3Bright
165.2Bright
175.2Bright
185.2Bright
195.2Bright
205.1Bright
215.1Bright
225.1Bright
235.1Bright
245.1Bright
255.1Bright
265.0Bright
275.0Bright
285.0Bright
295.0Bright
305.0Bright
315.0Bright
Planning a trip in May

Hazard calendar for Sam Roi Yot

In seasonPeak

In May, Sam Roi Yot sits inside its cyclone and rainy season 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 May a good time to visit Sam Roi Yot?

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

2.1
Sightseeing
12th-best month of the year
3.9
Beach & pool
11th-best month of the year

May is a weaker month for outdoor sightseeing in Sam Roi Yot.

What to pack for Sam Roi Yot in May

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

In May, Sam Roi Yot sees daytime highs around 33°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 25 days see rain.

light clothesrain gearsun protection

Sea temperature near Sam Roi Yot in May

The nearest coast averages about 30°C in May — 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 May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 12 (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 May

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where May 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
May 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).