San José weather in May

In May, San José sees average daytime highs of 28°C and overnight lows near 24°C, with 223 mm of rain across 26.7 wet days and about 12.5 hours of daylight. It is the 2nd-warmest and 7th-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 10% of the time in May, and the air most often feels oppressive.

Daylight stretches from about 12 h 24 min at the start of May to 12 h 36 min by month's end. Set against the rest of the year, May is San José's 7th-clearest and 9th-windiest month. For the whole year in context, see San José's year-round climate.

Daytime high
28°
2nd warmest
Overnight low
24°
12th coldest
Rainfall
223 mm
26.7 wet days
Daylight
12 h 30 min
5:22 AM – 5:52 PM
Cloud cover
77%
7th clearest
Wind
13 km/h
9th windiest
Solar energy
5.07 kWh/m²
Travel score
3.7
out of 10

San José is populated place in Upala district of Costa Rico.

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 28°C through the month.

A typical May day in San José reaches about 28°C in the afternoon and slips back to 24°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 29°C. Set against its neighbours, May runs on par with April and on par with June.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12824
22824
32824
42824
52824
62824
72824
82824
92824
102824
112824
122824
132824
142824
152824
162824
172824
182824
192824
202824
212824
222824
232824
242824
252724
262724
272724
282724
292724
302724
312724

San José weather by month

How May compares with the rest of the year at a glance. May is the 2nd-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 22°17126.811.44.5
Feb27° / 22°11322.111.64.8
Mar28° / 23°8019.811.95.3
Apr28° / 23°6318.112.24.8
May28° / 24°22326.712.53.7
Jun27° / 24°28129.412.63.3
Jul27° / 23°30830.612.63.4
Aug27° / 23°25930.512.43.4
Sep27° / 23°26029.312.13.4
Oct27° / 23°29929.311.83.5
Nov26° / 23°26226.211.54.0
Dec26° / 22°21427.311.44.2

Cloud cover in May

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 10% 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 77%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
13763
23664
33664
43466
53367
63268
73268
83169
93070
102971
112872
122674
132575
142476
152377
162278
172278
182080
191981
201882
211882
221882
231783
241585
251585
261585
271585
281486
291486
301486
311387

Chance of precipitation in May

Any precipitation

San José gets around 223 mm of rain over 26.7 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 86% and peaks near 95% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
173
274
375
476
577
677
778
879
980
1080
1181
1283
1384
1485
1586
1687
1788
1890
1991
2091
2192
2293
2393
2494
2594
2694
2794
2894
2995
3095
3195

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 95% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202531
Muggy (%)Oppressive (%)Miserable (%)
112880
211890
310900
49910
58920
67930
77930
86940
96940
105950
115941
124951
134951
144951
153961
163961
172971
182962
192962
202962
211972
221972
231972
241972
251972
260982
270991
280991
290991
300991
310991

Wind in May

Winds average 13 km/h in May.

Across May, daily wind ranges from about 10 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202531
Wind speed (km/h)Feels
115light breeze
215light breeze
315light breeze
415light breeze
515light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1812light breeze
1912light breeze
2012calm
2112calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3010calm
3110calm

Sunrise & sunset in May

DaylightNight

Daylight runs from about 12 h 24 min at the start of May to 12 h 36 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 5:26 AM to 5:20 AM, and sunset from 5:49 PM to 5:56 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.45:265:49
212.45:265:49
312.45:255:49
412.45:255:50
512.45:255:50
612.45:245:50
712.45:245:50
812.45:245:50
912.45:235:50
1012.55:235:51
1112.55:235:51
1212.55:235:51
1312.55:225:51
1412.55:225:51
1512.55:225:52
1612.55:225:52
1712.55:225:52
1812.55:215:52
1912.55:215:53
2012.55:215:53
2112.55:215:53
2212.55:215:53
2312.55:215:53
2412.65:215:54
2512.65:205:54
2612.65:205:54
2712.65:205:55
2812.65:205:55
2912.65:205:55
3012.65:205:55
3112.65:205:56

Solar energy in May

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in May, about 5.07 kWh/m².

For context, solar energy here swings from a low near 3.98 kWh/m² to a high of 6.04 kWh/m² in April across the year — May's 5.07 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.7Bright
25.6Bright
35.6Bright
45.5Bright
55.5Bright
65.5Bright
75.4Bright
85.4Bright
95.3Bright
105.3Bright
115.3Bright
125.2Bright
135.2Bright
145.1Bright
155.1Bright
165.0Bright
175.0Bright
185.0Bright
194.9Bright
204.9Bright
214.8Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.7Bright
284.7Bright
294.7Bright
304.7Bright
314.7Bright
Planning a trip in May

Is May a good time to visit San José?

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

3.7
Sightseeing
7th-best month of the year
4.2
Beach & pool
5th-best month of the year

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

What to pack for San José in May

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

In May, San José sees daytime highs around 28°C and nights near 24°C. Pack light clothes and rain gear. Worth having: sun protection. About 27 days see rain.

light clothesrain gearsun protection

Sea temperature near San José in May

The nearest coast averages about 29°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 65 km away) is warmest in May at about 29°C and coldest in February near 27°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr29Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct28Tropical
Nov28Warm
Dec27Warm

UV index in San José in May

LowModerateHighVery highExtreme

Clear-sky midday UV in May peaks around 13 (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 José peaks around March 18 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 highMar 18UV 14Dec 16UV 9
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar14Extreme
Apr14Extreme
May13Extreme
Jun13Extreme
Jul12Extreme
Aug13Extreme
Sep12Extreme
Oct12Extreme
Nov11Extreme
Dec9Very high

Air quality in San José 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 José is worst in July — around 23 µg/m³ PM2.5 (moderate), about 3.8× the cleanest month (December, 6 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1622 µg/m³Dec 166 µg/m³
PM2.5 (µg/m³)Level
Jan7Good
Feb8Good
Mar9Good
Apr19Moderate
May21Moderate
Jun19Moderate
Jul23Moderate
Aug18Moderate
Sep13Moderate
Oct9Good
Nov6Good
Dec6Good
Location & terrain

Where is San José?

San José sits at 11.0°N, 85.1°W, 50 m above sea level, in Costa Rica. The nearest listed city is San Carlos, 44 km away.

San CarlosLiberiaCañasLa FortunaMonteverdeEl CastilloSan Juan del Sur

Topography around San José

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

Within 3 km, the terrain around San José has only modest variations in elevation — a maximum elevation change of 55 m around an average of 51 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 659 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,977 m.

The land around San José is covered by grassland (51%) and trees (48%) within 3 km, trees (59%) and grassland (36%) within 16 km, and trees (45%), water (27%) and grassland (24%) within 80 km.

3 km
55 m
16 km
659 m
80 km
1,977 m
treesgrasslandcroplandartificial surfaceswater
May weather nearby: San Carlos 44 km · Liberia 48 km · Cañas 58 km · La Fortuna 76 km · Monteverde 80 km · El Castillo 81 km · San Juan del Sur 87 km · Rivas 93 km

Costa Rica travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 59% of US
price level, 2025
GDP per capita
$19,970
2025
Happiness
7.4 / 10
World Happiness, 2025
Safe drinking water
81%
of population, 2024
Homicide rate
17.7
per 100k, 2023
Road deaths
14.8
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 516
Religion
Roman Catholic 48%none 27%Evangelical and Pentecostal 20%other 3%

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 José (10.9519°, -85.1357°, elevation 50 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. 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).