Ratchaburi weather in May

In May, Ratchaburi sees average daytime highs of 35°C and overnight lows near 27°C, with 127 mm of rain across 21.9 wet days and about 12.6 hours of daylight. It is the 2nd-warmest and 5th-wettest month of the year here.

Day-to-day highs hold fairly steady near 35°C through the month. The sky is clear or mostly clear about 9% of the time in May, and the air most often feels miserable.

Daylight stretches from about 12 h 30 min at the start of May to 12 h 42 min by month's end. Set against the rest of the year, May is Ratchaburi's 8th-clearest and 10th-windiest month. For the whole year in context, see Ratchaburi's year-round climate.

Daytime high
35°
2nd warmest
Overnight low
27°
12th coldest
Rainfall
127 mm
21.9 wet days
Daylight
12 h 36 min
5:58 AM – 6:36 PM
Cloud cover
79%
8th clearest
Wind
7 km/h
10th windiest
Solar energy
5.51 kWh/m²
Travel score
1.7
out of 10

Ratchaburi is town in Ratchaburi province, Thailand.

Air quality
High
PM2.5 30 µg/m³ · 2019
Density
10,626/km²
people per km²

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 35°C through the month.

A typical May day in Ratchaburi reaches about 35°C in the afternoon and slips back to 27°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 32°C and 38°C. Set against its neighbours, May runs about 1°C cooler than April and about 1°C warmer than June.

25°30°35°40°151015202531
Avg high (°C)Avg low (°C)
13627
23627
33627
43627
53627
63627
73627
83527
93527
103527
113527
123527
133527
143527
153527
163527
173527
183527
193527
203527
213527
223527
233527
243527
253527
263527
273527
283427
293427
303427
313427

How May really feels in Ratchaburi

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
31 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.

Ratchaburi weather by month

How May compares with the rest of the year at a glance. May is the 2nd-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 22°122.211.35.3
Feb33° / 23°102.411.54.2
Mar35° / 25°376.411.93.0
Apr36° / 27°6811.212.31.9
May35° / 27°12721.912.61.7
Jun34° / 27°11420.512.82.1
Jul33° / 26°13322.112.72.3
Aug33° / 26°14323.112.42.4
Sep32° / 26°19724.112.12.3
Oct32° / 25°18821.111.73.2
Nov31° / 24°456.411.44.6
Dec31° / 22°102.211.25.5

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 9% 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 79%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14357
24258
34060
43862
53763
63565
73367
83169
92971
102773
112575
122377
132179
142080
151981
161882
171585
181486
191486
201288
211288
221090
231090
241090
251090
261090
27991
28991
29892
30892
31793

Chance of precipitation in May

Any precipitation

Ratchaburi gets around 127 mm of rain over 21.9 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 70% and peaks near 79% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
154
256
357
458
560
661
762
863
964
1066
1167
1268
1369
1470
1571
1672
1773
1874
1974
2075
2176
2276
2377
2477
2578
2678
2778
2879
2979
3078
3178

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the miserable band about 59% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
115148
214949
314851
414653
514554
614455
714356
814257
904258
1004159
1104159
1204060
1304060
1404060
1504060
1604060
1704060
1804060
1904060
2004060
2103961
2203961
2303961
2403862
2503862
2603763
2703763
2803664
2903664
3003565
3103565

Wind in May

Winds average 7 km/h in May.

Across May, daily wind ranges from about 7 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm
317calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 30 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 12 minutes over May. Sunrise moves from 6:04 AM to 5:56 AM, and sunset from 6:32 PM to 6:40 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.56:046:32
212.56:036:32
312.56:036:33
412.56:026:33
512.56:026:33
612.56:026:33
712.56:016:33
812.56:016:34
912.66:006:34
1012.66:006:34
1112.66:006:34
1212.65:596:35
1312.65:596:35
1412.65:596:35
1512.65:596:35
1612.65:586:36
1712.65:586:36
1812.65:586:36
1912.65:586:37
2012.75:576:37
2112.75:576:37
2212.75:576:37
2312.75:576:38
2412.75:576:38
2512.75:576:38
2612.75:566:39
2712.75:566:39
2812.75:566:39
2912.75:566:40
3012.75:566:40
3112.75:566:40

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.51 kWh/m².

For context, solar energy here swings from a low near 4.41 kWh/m² to a high of 6.21 kWh/m² in April across the year — May's 5.51 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.9Bright
25.9Bright
35.9Bright
45.8Bright
55.8Bright
65.8Bright
75.8Bright
85.7Bright
95.7Bright
105.7Bright
115.6Bright
125.6Bright
135.5Bright
145.5Bright
155.5Bright
165.5Bright
175.4Bright
185.4Bright
195.4Bright
205.4Bright
215.3Bright
225.3Bright
235.3Bright
245.3Bright
255.3Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.3Bright
315.2Bright
Planning a trip in May

Hazard calendar for Ratchaburi

In seasonPeak

In May, Ratchaburi sits inside its cyclone and monsoon season. The full year is below, with each hazard's peak months called out.

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

Ratchaburi's monsoon runs May–October, when most of the year's rain falls.

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

Is May a good time to visit Ratchaburi?

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

1.7
Sightseeing
12th-best month of the year
3.8
Beach & pool
12th-best month of the year

May is a weaker month for outdoor sightseeing in Ratchaburi.

What to pack for Ratchaburi in May

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

In May, Ratchaburi sees daytime highs around 35°C and nights near 27°C. Pack light clothes and rain gear. Worth having: sun protection. About 22 days see rain.

light clothesrain gearsun protection

Sea temperature near Ratchaburi in May

The nearest coast averages about 31°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 38 km away) is warmest in May at about 31°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
May31Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct29Tropical
Nov29Tropical
Dec28Warm

UV index in Ratchaburi in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ratchaburi peaks around August 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 20 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 15UV 13Nov 20UV 8
UV index (midday)Level
Jan8Very high
Feb9Very high
Mar12Extreme
Apr11Extreme
May11Extreme
Jun12Extreme
Jul12Extreme
Aug13Extreme
Sep12Extreme
Oct10Very high
Nov8Very high
Dec9Very high

Air quality in Ratchaburi 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 Ratchaburi is worst in February — around 44 µg/m³ PM2.5 (poor), about 2.6× the cleanest month (August, 17 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Ratchaburi's WHO annual average of 30 µg/m³.

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorModerateFeb 1844 µg/m³Aug 1017 µg/m³
PM2.5 (µg/m³)Level
Jan42Poor
Feb44Poor
Mar43Poor
Apr33Moderate
May23Moderate
Jun17Moderate
Jul17Moderate
Aug17Moderate
Sep21Moderate
Oct33Moderate
Nov35Moderate
Dec34Moderate
Location & terrain

Where is Ratchaburi?

Ratchaburi sits at 13.5°N, 99.8°E, 8 m above sea level, in Thailand. The nearest listed city is Damnoen Saduak, 15 km away.

Topography around Ratchaburi

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

Within 3 km, the terrain around Ratchaburi has only modest variations in elevation — a maximum elevation change of 43 m around an average of 8 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 231 m; within 80 km, large variations in elevation — a maximum elevation change of 1,189 m.

The land around Ratchaburi is covered by artificial surfaces (47%) and trees (27%) within 3 km, trees (50%) and cropland (29%) within 16 km, and trees (44%) and cropland (25%) within 80 km.

3 km
43 m
16 km
231 m
80 km
1,189 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Damnoen Saduak 15 km · Photharam 18 km · Bang Phae 21 km · Ban I Chang 21 km · Samut Songkhram 24 km · Chom Bueng 26 km · Ban Pong 32 km · Ban Phaeo 32 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 Ratchaburi (13.5367°, 99.8171°, elevation 8 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).