San José weather in January

In January, San José sees average daytime highs of 26°C and overnight lows near 22°C, with 171 mm of rain across 26.8 wet days and about 11.4 hours of daylight. It is the 11th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 26°C through the month. The sky is clear or mostly clear about 48% of the time in January, and the air most often feels muggy.

Daylight stretches from about 11 h 24 min at the start of January to 11 h 30 min by month's end. Set against the rest of the year, January is San José's 3rd-clearest and 1st-windiest month. For the whole year in context, see San José's year-round climate.

Daytime high
26°
11th warmest
Overnight low
22°
1st coldest
Rainfall
171 mm
26.8 wet days
Daylight
11 h 24 min
6:07 AM – 5:33 PM
Cloud cover
46%
3rd clearest
Wind
21 km/h
1st windiest
Solar energy
4.55 kWh/m²
Travel score
4.5
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 January

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 26°C through the month.

A typical January day in San José reaches about 26°C in the afternoon and slips back to 22°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 27°C. Set against its neighbours, January runs on par with December and on par with February.

20°23°25°28°30°151015202531
Avg high (°C)Avg low (°C)
12622
22622
32622
42622
52622
62622
72622
82622
92622
102622
112622
122622
132622
142622
152622
162622
172622
182622
192622
202622
212622
222622
232622
242622
252622
262622
272622
282622
292622
302622
312622

San José weather by month

How January compares with the rest of the year at a glance. January is the 11th-warmest and 9th-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 January

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 48% of the time in January.

Beyond those clear spells, partly cloudy skies cover about 28% of January, with mostly cloudy or overcast conditions the remaining 24%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17129
27129
37129
47228
57228
67228
77327
87228
97228
107228
117228
127228
137228
147327
157426
167525
177525
187624
197723
207822
217822
227921
237921
248119
258119
268218
278218
288218
298218
308317
318317

Chance of precipitation in January

Any precipitation

San José gets around 171 mm of rain over 26.8 wet days in January. 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 90% on the wettest days.

0%20%40%60%80%100%151015202531
Rain chance (%)
190
290
390
489
589
688
788
887
987
1087
1186
1286
1385
1485
1585
1685
1785
1885
1985
2085
2185
2285
2385
2485
2584
2684
2784
2884
2984
3084
3184

Humidity in January

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, January lands in the muggy band about 61% of days. Sticky, muggy-or-worse air turns up on roughly 96% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)
134156
234255
334453
444551
544749
644947
745145
845343
945541
1055639
1155837
1256035
1356233
1456431
1556530
1656629
1756728
1856728
1956827
2056827
2156926
2256926
2356926
2447026
2547026
2647026
2747026
2847026
2947026
3037126
3137225

Wind in January

Winds average 21 km/h in January, the windiest month of the year.

Across January, daily wind ranges from about 21 km/h on the calmest days to 21 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202531
Wind speed (km/h)Feels
121breezy
221breezy
321breezy
421breezy
521breezy
621breezy
721breezy
821breezy
921breezy
1021breezy
1121breezy
1221breezy
1321breezy
1421breezy
1521breezy
1621breezy
1721breezy
1821breezy
1921breezy
2021breezy
2121breezy
2221breezy
2321breezy
2421breezy
2521breezy
2621breezy
2721breezy
2821breezy
2921breezy
3021breezy
3121breezy

Sunrise & sunset in January

DaylightNight

Daylight runs from about 11 h 24 min at the start of January to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 6 minutes over January. Sunrise moves from 6:03 AM to 6:08 AM, and sunset from 5:25 PM to 5:39 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.46:035:25
211.46:035:25
311.46:035:26
411.46:045:26
511.46:045:27
611.46:045:27
711.46:055:28
811.46:055:28
911.46:055:29
1011.46:065:29
1111.46:065:30
1211.46:065:30
1311.46:065:31
1411.46:075:32
1511.46:075:32
1611.46:075:33
1711.46:075:33
1811.46:085:34
1911.46:085:34
2011.46:085:34
2111.56:085:35
2211.56:085:35
2311.56:085:36
2411.56:085:36
2511.56:085:37
2611.56:085:37
2711.56:085:38
2811.56:085:38
2911.56:085:39
3011.56:085:39
3111.56:085:39

Solar energy in January

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in January, about 4.55 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 — January's 4.55 kWh/m² falls in the middle.

024151015202531
Solar energy (kWh/m²)Level
14.3Bright
24.3Bright
34.3Bright
44.3Bright
54.3Bright
64.4Bright
74.4Bright
84.4Bright
94.4Bright
104.4Bright
114.5Bright
124.5Bright
134.5Bright
144.5Bright
154.5Bright
164.6Bright
174.6Bright
184.6Bright
194.6Bright
204.6Bright
214.7Bright
224.7Bright
234.7Bright
244.7Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.9Bright
314.9Bright
Planning a trip in January

Is January a good time to visit San José?

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

4.5
Sightseeing
4th-best month of the year
4.2
Beach & pool
4th-best month of the year

January is a reasonable time to visit San José for sightseeing.

What to pack for San José in January

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

In January, San José sees daytime highs around 26°C and nights near 22°C. Pack rain gear. Worth having: light clothes, sun protection and a windbreaker. About 27 days see rain.

rain gearlight clothessun protectiona windbreaker

Sea temperature near San José in January

The nearest coast averages about 27°C in January — 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 January

LowModerateHighVery highExtreme

Clear-sky midday UV in January 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 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 January

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where January 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
January 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).