Roi Et weather in May

In May, Roi Et sees average daytime highs of 34°C and overnight lows near 26°C, with 180 mm of rain across 21.3 wet days and about 12.7 hours of daylight. It is the 3rd-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 34°C through the month. The sky is clear or mostly clear about 11% of the time in May, and the air most often feels miserable.

Daylight stretches from about 12 h 36 min at the start of May to 12 h 54 min by month's end. Set against the rest of the year, May is Roi Et's 8th-clearest and 11th-windiest month. For the whole year in context, see Roi Et's year-round climate.

Daytime high
34°
3rd warmest
Overnight low
26°
12th coldest
Rainfall
180 mm
21.3 wet days
Daylight
12 h 42 min
5:39 AM – 6:24 PM
Cloud cover
78%
8th clearest
Wind
8 km/h
11th windiest
Solar energy
5.6 kWh/m²
Travel score
2.0
out of 10

Roi Et is town in Roi Et province, Thailand.

Density
3,382/km²
people per km²
Founded
1937

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 34°C through the month.

A typical May day in Roi Et reaches about 34°C in the afternoon and slips back to 26°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 37°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)
13526
23526
33526
43526
53526
63526
73526
83526
93526
103526
113526
123526
133526
143426
153426
163426
173426
183426
193426
203426
213426
223426
233426
243426
253426
263426
273426
283426
293426
303426
313426

How May really feels in Roi Et

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.

Roi Et weather by month

How May compares with the rest of the year at a glance. May is the 3rd-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 18°61.611.25.9
Feb33° / 20°112.111.54.6
Mar35° / 24°376.511.92.9
Apr36° / 26°6611.312.42.1
May34° / 26°18021.312.72.0
Jun33° / 26°16921.212.92.2
Jul33° / 26°20723.512.92.4
Aug32° / 25°24025.212.52.5
Sep32° / 25°25324.512.12.7
Oct31° / 24°10912.511.64.0
Nov31° / 22°243.511.35.2
Dec30° / 19°51.211.16.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 11% of the time in May.

Beyond those clear spells, partly cloudy skies cover about 14% of May, with mostly cloudy or overcast conditions the remaining 76%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24654
34555
44357
54159
63961
73664
83466
93367
103169
112872
122674
132575
142377
152278
161981
171783
181783
191585
201585
211486
221387
231387
241387
251387
261486
271486
281486
291486
301486
311486

Chance of precipitation in May

Any precipitation

Roi Et gets around 180 mm of rain over 21.3 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 68% and peaks near 75% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
154
255
357
458
559
660
761
862
963
1065
1166
1267
1368
1469
1570
1671
1772
1872
1973
2073
2174
2274
2374
2474
2574
2674
2775
2875
2975
3075
3175

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 50% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1196723
2186625
3176527
4176230
5066232
6056134
7055837
8045739
9045541
10035443
11035344
12025246
13025147
14024948
15024850
16024751
17014653
18014554
19014356
20014257
21014158
22013960
23013861
24013762
25003565
26003466
27003268
28003169
29002971
30002872
31002872

Wind in May

Winds average 8 km/h in May.

Across May, 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
18calm
28calm
38calm
48calm
58calm
68calm
78calm
88calm
98calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
299calm
309calm
319calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 36 min at the start of May to 12 h 54 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 5:46 AM to 5:36 AM, and sunset from 6:20 PM to 6:29 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.65:466:20
212.65:456:20
312.65:446:20
412.65:446:20
512.65:446:21
612.65:436:21
712.65:436:21
812.75:426:22
912.75:426:22
1012.75:416:22
1112.75:416:22
1212.75:416:23
1312.75:406:23
1412.75:406:23
1512.75:406:24
1612.75:396:24
1712.85:396:24
1812.85:396:25
1912.85:386:25
2012.85:386:25
2112.85:386:26
2212.85:386:26
2312.85:386:26
2412.85:376:27
2512.85:376:27
2612.85:376:27
2712.85:376:28
2812.95:376:28
2912.95:376:28
3012.95:376:29
3112.95:366:29

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.6 kWh/m².

For context, solar energy here swings from a low near 4.47 kWh/m² to a high of 6.16 kWh/m² in April across the year — May's 5.6 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
16.0Bright
26.0Bright
35.9Bright
45.9Bright
55.9Bright
65.8Bright
75.8Bright
85.8Bright
95.8Bright
105.7Bright
115.7Bright
125.7Bright
135.6Bright
145.6Bright
155.6Bright
165.6Bright
175.5Bright
185.5Bright
195.5Bright
205.5Bright
215.5Bright
225.5Bright
235.5Bright
245.5Bright
255.4Bright
265.4Bright
275.4Bright
285.4Bright
295.4Bright
305.4Bright
315.4Bright
Planning a trip in May

Hazard calendar for Roi Et

In seasonPeak

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

Roi Et's monsoon runs May–September, when most of the year's rain falls.

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

Is May a good time to visit Roi Et?

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

2.0
Sightseeing
12th-best month of the year
4.1
Beach & pool
11th-best month of the year

May is a weaker month for outdoor sightseeing in Roi Et.

What to pack for Roi Et in May

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

In May, Roi Et sees daytime highs around 34°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 21 days see rain.

light clothesrain gearsun protection

UV index in Roi Et 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 Roi Et peaks around August 11 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 10 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 11UV 13Dec 10UV 8
UV index (midday)Level
Jan9Very high
Feb11Extreme
Mar12Extreme
Apr10Very high
May11Extreme
Jun12Extreme
Jul13Extreme
Aug13Extreme
Sep12Extreme
Oct11Extreme
Nov8Very high
Dec8Very high

Air quality in Roi Et 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 Roi Et is worst in March — around 52 µg/m³ PM2.5 (poor), about 2.6× the cleanest month (December, 20 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateMar 1751 µg/m³Dec 1320 µg/m³
PM2.5 (µg/m³)Level
Jan28Moderate
Feb40Poor
Mar52Poor
Apr41Poor
May30Moderate
Jun22Moderate
Jul24Moderate
Aug25Moderate
Sep28Moderate
Oct28Moderate
Nov23Moderate
Dec20Moderate
Location & terrain

Where is Roi Et?

Roi Et sits at 16.1°N, 103.7°E, 148 m above sea level, in Thailand. The nearest listed city is Ban Selaphum, 32 km away.

Topography around Roi Et

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

Within 3 km, the terrain around Roi Et has only modest variations in elevation — a maximum elevation change of 30 m around an average of 147 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 61 m; within 80 km, significant variations in elevation — a maximum elevation change of 385 m.

The land around Roi Et is covered by artificial surfaces (41%) and trees (34%) within 3 km, cropland (76%) within 16 km, and cropland (79%) within 80 km.

3 km
30 m
16 km
61 m
80 km
385 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: Ban Selaphum 32 km · Kamalasai 32 km · Maha Sarakham 40 km · Kalasin 45 km · Kaset Wisai 45 km · Yasothon 60 km · Kuchinarai 69 km · Nong Kung Si 76 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 Roi Et (16.0567°, 103.6531°, elevation 148 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. 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).