San Marcos weather in May

In May, San Marcos sees average daytime highs of 21°C and overnight lows near 13°C, with 323 mm of rain across 29.7 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 21°C through the month. The sky is clear or mostly clear about 5% of the time in May, and the air most often feels comfortable.

Daylight stretches from about 12 h 30 min at the start of May to 12 h 48 min by month's end. Set against the rest of the year, May is San Marcos's 7th-clearest and 12th-windiest month. For the whole year in context, see San Marcos's year-round climate.

Daytime high
21°
3rd warmest
Overnight low
13°
11th coldest
Rainfall
323 mm
29.7 wet days
Daylight
12 h 42 min
5:43 AM – 6:24 PM
Cloud cover
80%
7th clearest
Wind
4 km/h
12th windiest
Solar energy
5.45 kWh/m²
Travel score
3.5
out of 10

Temperature in May

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 21°C through the month.

A typical May day in San Marcos reaches about 21°C in the afternoon and slips back to 13°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 23°C. Set against its neighbours, May runs on par with April and on par with June.

10°15°20°25°151015202531
Avg high (°C)Avg low (°C)
12112
22112
32112
42112
52113
62113
72113
82113
92113
102113
112113
122113
132113
142113
152113
162113
172113
182113
192113
202113
212113
222113
232113
242113
252113
262113
272113
282113
292113
302113
312113

San Marcos 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
Jan20° / 10°247.411.26.9
Feb21° / 10°257.911.57.0
Mar21° / 11°6416.711.95.8
Apr21° / 12°12423.812.34.5
May21° / 13°32329.712.73.5
Jun20° / 13°41629.212.93.3
Jul20° / 12°26828.312.83.6
Aug20° / 12°32529.712.53.4
Sep20° / 13°41529.712.13.2
Oct20° / 12°29328.811.73.5
Nov20° / 11°851811.35.1
Dec19° / 10°348.611.16.6

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 85%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
12971
22971
32773
42773
52575
62476
72476
82278
92179
101981
111882
121882
131684
141585
151486
161387
171288
181189
191090
201090
211090
221090
231090
24991
25991
26991
27991
28991
29793
30793
31793

Chance of precipitation in May

Any precipitation

San Marcos gets around 323 mm of rain over 29.7 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 95% and peaks near 98% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
192
293
393
494
594
694
794
894
994
1094
1194
1294
1395
1495
1595
1695
1795
1896
1996
2096
2196
2297
2397
2497
2597
2697
2798
2898
2998
3098
3198

Humidity in May

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, May lands in the comfortable band about 64% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)
154451
252471
351481
449491
548511
647521
745541
844551
942571
1041572
1139592
1238602
1337612
1435632
1534642
1633652
1731672
1830682
1929692
2028702
2127712
2227712
2326722
2426722
2525732
2624742
2724742
2823752
2922771
3021781
3121781

Wind in May

Winds average 4 km/h in May, the calmest month.

Across May, daily wind ranges from about 4 km/h on the calmest days to 4 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202531
Wind speed (km/h)Feels
14calm
24calm
34calm
44calm
54calm
64calm
74calm
84calm
94calm
104calm
114calm
124calm
134calm
144calm
154calm
164calm
174calm
184calm
194calm
204calm
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 30 min at the start of May to 12 h 48 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 5:49 AM to 5:40 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)
112.55:496:20
212.55:486:20
312.65:486:21
412.65:476:21
512.65:476:21
612.65:466:21
712.65:466:22
812.65:456:22
912.65:456:22
1012.65:456:22
1112.65:446:23
1212.75:446:23
1312.75:446:23
1412.75:436:24
1512.75:436:24
1612.75:436:24
1712.75:426:25
1812.75:426:25
1912.75:426:25
2012.75:426:25
2112.75:416:26
2212.75:416:26
2312.85:416:26
2412.85:416:27
2512.85:416:27
2612.85:416:27
2712.85:406:28
2812.85:406:28
2912.85:406:28
3012.85:406:29
3112.85:406:29

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.45 kWh/m².

For context, solar energy here swings from a low near 4.48 kWh/m² to a high of 6.24 kWh/m² in April across the year — May's 5.45 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
95.7Bright
105.7Bright
115.7Bright
125.6Bright
135.6Bright
145.5Bright
155.5Bright
165.5Bright
175.4Bright
185.4Bright
195.3Bright
205.3Bright
215.2Bright
225.2Bright
235.2Bright
245.1Bright
255.1Bright
265.0Bright
275.0Bright
285.0Bright
295.0Bright
304.9Bright
314.9Bright
Planning a trip in May

Hazard calendar for San Marcos

In seasonPeak

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

San Marcos's rainy season runs May–October, when most of the year's rain falls.

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

Is May a good time to visit San Marcos?

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

3.5
Sightseeing
8th-best month of the year
2.1
Beach & pool
7th-best month of the year

May is a weaker month for outdoor sightseeing in San Marcos.

What to pack for San Marcos in May

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

In May, San Marcos sees daytime highs around 21°C and nights near 13°C. Pack rain gear. Worth having: sun protection. About 30 days see rain.

rain gearsun protection

UV index in San Marcos 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 San Marcos peaks around April 12 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 9 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highApr 12UV 14Dec 16UV 9
UV index (midday)Level
Jan9Very high
Feb13Extreme
Mar14Extreme
Apr14Extreme
May12Extreme
Jun13Extreme
Jul13Extreme
Aug13Extreme
Sep12Extreme
Oct11Extreme
Nov9Very high
Dec9Very high

Air quality in San Marcos 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 San Marcos is worst in May — around 34 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateMay 934 µg/m³Aug 1622 µg/m³
PM2.5 (µg/m³)Level
Jan23Moderate
Feb22Moderate
Mar25Moderate
Apr34Moderate
May34Moderate
Jun23Moderate
Jul23Moderate
Aug22Moderate
Sep23Moderate
Oct23Moderate
Nov23Moderate
Dec25Moderate
Location & terrain

Where is San Marcos?

San Marcos sits at 15.0°N, 91.8°W, 2,380 m above sea level, in Guatemala. The nearest listed city is San Pedro Sacatepéquez, 4.0 km away.

La EsperanzaMalacatánColombaCoatepeque

Topography around San Marcos

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

Within 3 km, the terrain around San Marcos has large variations in elevation — a maximum elevation change of 814 m around an average of 2,422 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 3,414 m; within 80 km, extreme variations in elevation — a maximum elevation change of 4,178 m.

The land around San Marcos is covered by trees (47%), artificial surfaces (30%) and cropland (22%) within 3 km, trees (80%) within 16 km, and trees (69%) within 80 km.

3 km
814 m
16 km
3,414 m
80 km
4,178 m
treesshrubsgrasslandcroplandartificial surfaceswatermangroves
May weather nearby: San Pedro Sacatepéquez 4.0 km · Comitancillo 15 km · Cabricán 20 km · Ostuncalco 21 km · La Esperanza 27 km · Malacatán 29 km · Colomba 29 km · Coatepeque 30 km

Guatemala travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 43% of US
price level, 2025
GDP per capita
$6,598
2025
Happiness
6.5 / 10
World Happiness, 2025
Safe drinking water
49%
of population, 2024
Homicide rate
23.4
per 100k, 2023
Road deaths
22.9
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Moderate
EF EPI 510
Religion
Evangelical 46%Roman Catholic 42%none 11%

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 San Marcos (14.9644°, -91.7949°, elevation 2,380 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).