Xam Nua weather in May

In May, Xam Nua sees average daytime highs of 28°C and overnight lows near 20°C, with 209 mm of rain across 23.6 wet days and about 13 hours of daylight. It is the 2nd-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 11% of the time in May, and the air most often feels muggy.

Daylight stretches from about 12 h 42 min at the start of May to 13 h 06 min by month's end. Set against the rest of the year, May is Xam Nua's 8th-clearest and 6th-windiest month. For the whole year in context, see Xam Nua's year-round climate.

Daytime high
28°
2nd warmest
Overnight low
20°
9th coldest
Rainfall
209 mm
23.6 wet days
Daylight
13 hours
5:31 AM – 6:29 PM
Cloud cover
78%
8th clearest
Wind
6 km/h
6th windiest
Solar energy
5.18 kWh/m²
Travel score
4.0
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical May day in Xam Nua reaches about 28°C in the afternoon and slips back to 20°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 31°C. Set against its neighbours, May runs about 1°C warmer than April and on par with June.

15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12819
22819
32819
42819
52819
62819
72819
82819
92819
102819
112819
122819
132819
142819
152820
162820
172820
182820
192820
202820
212820
222820
232820
242820
252820
262820
272820
282820
292920
302920
312921

Xam Nua 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
Jan20° / 10°244.210.97.1
Feb22° / 12°173.711.37.7
Mar25° / 14°6310.211.96.9
Apr27° / 17°11317.412.55.4
May28° / 20°20923.6134.0
Jun29° / 21°21724.513.23.5
Jul28° / 21°27626.813.13.6
Aug27° / 20°31227.412.73.7
Sep26° / 19°20021.512.14.6
Oct24° / 17°9214.611.56.1
Nov22° / 14°317117.2
Dec20° / 11°183.610.87.2

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 13% 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 (%)
14357
24357
34159
44060
53961
63862
73763
83664
93466
103367
113070
122971
132872
142674
152575
162377
172179
182179
191981
201783
211783
221585
231486
241288
251288
261288
271090
281090
29991
30991
31991

Chance of precipitation in May

Any precipitation

Xam Nua gets around 209 mm of rain over 23.6 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 76% and peaks near 82% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202531
Rain chance (%)
171
271
371
472
572
672
772
873
973
1073
1174
1274
1375
1475
1576
1676
1777
1877
1978
2078
2178
2279
2379
2480
2580
2681
2781
2881
2982
3082
3182

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the muggy band about 77% of days. Sticky, muggy-or-worse air turns up on roughly 85% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
11523701
21522711
31521712
41420732
51419742
61418752
71417753
81416763
91415773
101414774
111413784
121412794
131411795
141411795
151410796
16149797
17149797
18038818
19038809
200387910
210377911
220377911
230277912
240267913
250267814
260267814
270257815
280157816
290157816
300147817
310147817

Wind in May

Winds average 6 km/h in May.

Across May, daily wind ranges from about 6 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
206calm
216calm
226calm
236calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm
316calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 42 min at the start of May to 13 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 24 minutes over May. Sunrise moves from 5:39 AM to 5:27 AM, and sunset from 6:23 PM to 6:35 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.75:396:23
212.85:386:23
312.85:386:24
412.85:376:24
512.85:366:25
612.85:366:25
712.85:356:25
812.95:356:26
912.95:346:26
1012.95:346:27
1112.95:336:27
1212.95:336:27
1312.95:326:28
1412.95:326:28
1513.05:316:29
1613.05:316:29
1713.05:316:29
1813.05:306:30
1913.05:306:30
2013.05:306:31
2113.05:296:31
2213.05:296:32
2313.15:296:32
2413.15:286:32
2513.15:286:33
2613.15:286:33
2713.15:286:34
2813.15:286:34
2913.15:276:34
3013.15:276:35
3113.15:276:35

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.18 kWh/m².

For context, solar energy here swings from a low near 3.3 kWh/m² to a high of 5.34 kWh/m² in April across the year — May's 5.18 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
15.4Bright
25.4Bright
35.4Bright
45.4Bright
55.4Bright
65.4Bright
75.4Bright
85.3Bright
95.3Bright
105.3Bright
115.3Bright
125.3Bright
135.2Bright
145.2Bright
155.2Bright
165.2Bright
175.1Bright
185.1Bright
195.1Bright
205.1Bright
215.1Bright
225.0Bright
235.0Bright
245.0Bright
255.0Bright
265.0Bright
275.0Bright
285.0Bright
295.0Bright
305.0Bright
315.0Bright
Planning a trip in May

Hazard calendar for Xam Nua

In seasonPeak

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

Xam Nua'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 Xam Nua?

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

4.0
Sightseeing
9th-best month of the year
4.6
Beach & pool
6th-best month of the year

May is a reasonable time to visit Xam Nua for sightseeing.

What to pack for Xam Nua in May

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

In May, Xam Nua sees daytime highs around 28°C and nights near 20°C. Pack light clothes and rain gear. Worth having: sun protection. About 24 days see rain.

light clothesrain gearsun protection

UV index in Xam Nua 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 Xam Nua peaks around August 12 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 7 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highExtremeVery highAug 12UV 14Dec 17UV 7
UV index (midday)Level
Jan8Very high
Feb10Very high
Mar10Extreme
Apr9Very high
May11Extreme
Jun14Extreme
Jul13Extreme
Aug14Extreme
Sep10Extreme
Oct10Very high
Nov8Very high
Dec7High

Air quality in Xam Nua 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 Xam Nua is worst in April — around 288 µg/m³ PM2.5 (very unhealthy), about 35.5× the cleanest month (August, 8 µg/m³).

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

0306090120150180210240270JanFebMarAprMayJunJulAugSepOctNovDecModerateUnhealthyVery unhealthyUnhealthyGoodModerateApr 15263 µg/m³Aug 128 µg/m³
PM2.5 (µg/m³)Level
Jan20Moderate
Feb28Moderate
Mar98Unhealthy
Apr288Very unhealthy
May64Unhealthy
Jun14Moderate
Jul9Good
Aug8Good
Sep11Good
Oct15Moderate
Nov15Moderate
Dec19Moderate
Location & terrain

Where is Xam Nua?

Xam Nua sits at 20.4°N, 104.0°E, 957 m above sea level, in Laos. The nearest listed city is Vieng Xai, 19 km away.

Sơn LaBản Na HỷThị Trấn Thuận ChâuÍt OngMuang PhônsavanNghĩa LộHòa Bình

Topography around Xam Nua

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

Within 3 km, the terrain around Xam Nua has significant variations in elevation — a maximum elevation change of 373 m around an average of 1,033 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,118 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,963 m.

The land around Xam Nua is covered by trees (65%) within 3 km, trees (83%) within 16 km, and trees (82%) within 80 km.

3 km
373 m
16 km
1,118 m
80 km
1,963 m
treesgrasslandcroplandartificial surfacesbare terrain
May weather nearby: Vieng Xai 19 km · Sơn La 102 km · Bản Na Hỷ 108 km · Thị Trấn Thuận Châu 119 km · Ít Ong 122 km · Muang Phônsavan 140 km · Nghĩa Lộ 140 km · Hòa Bình 142 km

Laos travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B / C / E / F
230 V · 50 Hz
Prices
≈ 23% of US
price level, 2025
GDP per capita
$2,325
2025
Happiness
5.5 / 10
World Happiness, 2025
Safe drinking water
35%
of population, 2024
Road deaths
17.9
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Low
EF EPI 461
Religion
Buddhist 65%none 31%other/not stated 2%Christian 2%

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 Xam Nua (20.4164°, 104.045°, elevation 957 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).