Nan weather in May

In May, Nan sees average daytime highs of 34°C and overnight lows near 25°C, with 166 mm of rain across 21.5 wet days and about 12.9 hours of daylight. It is the 3rd-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 35°C in the first days to 33°C by the end. The sky is clear or mostly clear about 18% of the time in May, and the air most often feels oppressive.

Daylight stretches from about 12 h 42 min at the start of May to 13 hours by month's end. Set against the rest of the year, May is Nan's 8th-clearest and 5th-windiest month. For the whole year in context, see Nan's year-round climate.

Daytime high
34°
3rd warmest
Overnight low
25°
11th coldest
Rainfall
166 mm
21.5 wet days
Daylight
12 h 54 min
5:47 AM – 6:40 PM
Cloud cover
73%
8th clearest
Wind
5 km/h
5th windiest
Solar energy
5.31 kWh/m²
Travel score
2.3
out of 10

Nan is town in Nan province, Thailand.

Air quality
High
PM2.5 29.5 µg/m³ · 2019

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

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 35°C in the first days to 33°C by the end.

A typical May day in Nan reaches about 34°C in the afternoon and slips back to 25°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 30°C and 37°C. Set against its neighbours, May runs about 2°C cooler than April and about 2°C warmer than June.

20°25°30°35°40°151015202531
Avg high (°C)Avg low (°C)
13524
23524
33524
43524
53424
63424
73424
83424
93425
103425
113425
123425
133425
143425
153425
163325
173325
183325
193325
203325
213325
223325
233325
243325
253325
263325
273325
283325
293325
303325
313325

How May really feels in Nan

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
17 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.

Nan weather by month

How May compares with the rest of the year at a glance. May is the 3rd-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 16°152116.4
Feb33° / 17°81.211.44.7
Mar35° / 20°304.611.92.9
Apr36° / 24°7811.612.42.2
May34° / 25°16621.512.92.3
Jun32° / 25°19023.413.12.5
Jul31° / 25°27326.5132.6
Aug31° / 24°31228.112.62.6
Sep31° / 24°22124.412.12.8
Oct31° / 23°7413.811.64.1
Nov31° / 20°223.511.15.4
Dec29° / 17°141.710.96.6

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 18% 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 68%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
16139
25941
35842
45545
55446
65149
74852
84753
94456
104258
114060
123862
133565
143268
153070
162872
172773
182476
192476
202278
212179
221981
231882
241684
251585
261486
271387
281288
291288
301090
311090

Chance of precipitation in May

Any precipitation

Nan gets around 166 mm of rain over 21.5 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 69% 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 (%)
157
258
359
460
561
662
763
864
965
1067
1168
1269
1370
1471
1571
1672
1772
1873
1973
2073
2174
2274
2374
2474
2574
2673
2774
2874
2974
3074
3175

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 72% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
19874
28884
37885
47876
56868
66859
758411
858312
948214
1048016
1147818
1247719
1347521
1447422
1547224
1637225
1737027
1836928
1936829
2036730
2126731
2226632
2326533
2426335
2526236
2626038
2715940
2815841
2915643
3015445
3115346

Wind in May

Winds average 5 km/h in May.

Across May, daily wind ranges from about 5 km/h on the calmest days to 5 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
15calm
25calm
35calm
45calm
55calm
65calm
75calm
85calm
95calm
105calm
115calm
125calm
135calm
145calm
155calm
165calm
175calm
185calm
195calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm
315calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 42 min at the start of May to 13 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over May. Sunrise moves from 5:54 AM to 5:43 AM, and sunset from 6:34 PM to 6:45 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:546:34
212.75:536:35
312.75:536:35
412.75:526:35
512.75:526:36
612.75:516:36
712.85:516:36
812.85:506:37
912.85:506:37
1012.85:496:37
1112.85:496:38
1212.85:486:38
1312.85:486:38
1412.95:476:39
1512.95:476:39
1612.95:476:40
1712.95:466:40
1812.95:466:40
1912.95:466:41
2012.95:456:41
2112.95:456:42
2213.05:456:42
2313.05:456:42
2413.05:446:43
2513.05:446:43
2613.05:446:43
2713.05:446:44
2813.05:446:44
2913.05:436:45
3013.05:436:45
3113.05:436:45

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.31 kWh/m².

For context, solar energy here swings from a low near 3.85 kWh/m² to a high of 6.22 kWh/m² in April across the year — May's 5.31 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.9Bright
25.9Bright
35.8Bright
45.8Bright
55.8Bright
65.7Bright
75.7Bright
85.6Bright
95.6Bright
105.5Bright
115.5Bright
125.4Bright
135.4Bright
145.3Bright
155.3Bright
165.3Bright
175.2Bright
185.2Bright
195.2Bright
205.1Bright
215.1Bright
225.1Bright
235.1Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
284.9Bright
294.9Bright
304.9Bright
314.9Bright
Planning a trip in May

Hazard calendar for Nan

In seasonPeak

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

Nan'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 Nan?

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

2.3
Sightseeing
11th-best month of the year
4.4
Beach & pool
8th-best month of the year

May is a weaker month for outdoor sightseeing in Nan.

What to pack for Nan in May

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

In May, Nan sees daytime highs around 34°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 22 days see rain.

light clothesrain gearsun protection

UV index in Nan 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 Nan peaks around August 12 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 7 (very high).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highAug 12UV 13Dec 17UV 7
UV index (midday)Level
Jan8Very high
Feb9Very high
Mar9Very high
Apr10Very high
May11Extreme
Jun13Extreme
Jul13Extreme
Aug13Extreme
Sep11Extreme
Oct10Very high
Nov8Very high
Dec7High

Air quality in Nan 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 Nan is worst in March — around 71 µg/m³ PM2.5 (unhealthy), about 4.2× the cleanest month (September, 17 µg/m³).

Seasonal pattern from CAMS reanalysis, scaled to Nan's WHO annual average of 29.5 µg/m³.

020406080JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorUnhealthyModerateMar 2270 µg/m³Sep 1517 µg/m³
PM2.5 (µg/m³)Level
Jan27Moderate
Feb39Poor
Mar71Unhealthy
Apr65Unhealthy
May28Moderate
Jun17Moderate
Jul17Moderate
Aug17Moderate
Sep17Moderate
Oct17Moderate
Nov18Moderate
Dec21Moderate
Location & terrain

Where is Nan?

Nan sits at 18.8°N, 100.8°E, 205 m above sea level, in Thailand. The nearest listed city is Dok Kham Tai, 93 km away.

Dok Kham TaiPhraePhayaoDen ChaiLampangUttaraditChiang RaiBan Houakhoua

Topography around Nan

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

Within 3 km, the terrain around Nan has only modest variations in elevation — a maximum elevation change of 61 m around an average of 208 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 478 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,915 m.

The land around Nan is covered by trees (39%), artificial surfaces (28%) and cropland (21%) within 3 km, trees (76%) within 16 km, and trees (87%) within 80 km.

3 km
61 m
16 km
478 m
80 km
1,915 m
treesgrasslandcroplandartificial surfacesbare terrainwater
May weather nearby: Dok Kham Tai 93 km · Phrae 98 km · Phayao 105 km · Den Chai 117 km · Lampang 146 km · Uttaradit 148 km · Chiang Rai 160 km · Ban Houakhoua 166 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 Nan (18.7838°, 100.779°, elevation 205 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).