San Isidro weather in March

In March, San Isidro sees average daytime highs of 25°C and overnight lows near 21°C, with 138 mm of rain across 25.6 wet days and about 11.9 hours of daylight. It is the 1st-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 25°C through the month. The sky is clear or mostly clear about 37% of the time in March, and the air most often feels muggy.

Daylight stretches from about 11 h 48 min at the start of March to 12 h 06 min by month's end. Set against the rest of the year, March is San Isidro's 2nd-clearest and 9th-windiest month. For the whole year in context, see San Isidro's year-round climate.

Daytime high
25°
1st warmest
Overnight low
21°
6th coldest
Rainfall
138 mm
25.6 wet days
Daylight
11 h 54 min
5:46 AM – 5:43 PM
Cloud cover
52%
2nd clearest
Wind
5 km/h
9th windiest
Solar energy
6.24 kWh/m²
Travel score
4.7
out of 10

San Isidro is district in Pérez Zeledón canton, San José province, Costa Rica.

Density
182/km²
people per km²
Founded
1892

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

Temperature in March

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 25°C through the month.

A typical March day in San Isidro reaches about 25°C in the afternoon and slips back to 21°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 26°C. Set against its neighbours, March runs on par with February and on par with April.

15°20°25°30°151015202531
Avg high (°C)Avg low (°C)
12520
22520
32520
42520
52520
62520
72520
82520
92521
102521
112521
122521
132521
142521
152521
162521
172521
182521
192521
202521
212521
222521
232521
242521
252521
262521
272521
282521
292521
302521
312521

San Isidro weather by month

How March compares with the rest of the year at a glance. March is the 1st-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan24° / 20°21025.211.54.8
Feb24° / 20°14021.611.75.1
Mar25° / 21°13825.611.94.7
Apr25° / 21°33028.612.23.8
May24° / 21°73030.812.43.4
Jun24° / 21°70929.912.53.4
Jul24° / 21°8333112.53.4
Aug24° / 21°9333112.33.4
Sep24° / 21°8083012.13.4
Oct24° / 20°95230.811.83.4
Nov24° / 20°92429.911.63.5
Dec24° / 20°41328.811.54.1

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in March.

Beyond those clear spells, partly cloudy skies cover about 28% of March, with mostly cloudy or overcast conditions the remaining 35%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
17426
27426
37426
47426
57426
67426
77327
87327
97327
107129
117129
127030
136832
146733
156733
166535
176535
186337
196337
206139
216040
226040
235842
245842
255743
265743
275644
285644
295545
305545
315347

Chance of precipitation in March

Any precipitation

San Isidro gets around 138 mm of rain over 25.6 wet days in March, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 83% and peaks near 91% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202531
Rain chance (%)
180
279
379
479
579
678
778
877
977
1077
1177
1277
1378
1478
1579
1680
1781
1882
1983
2084
2185
2286
2387
2488
2589
2689
2790
2890
2991
3091
3191

Humidity in March

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, March lands in the muggy band about 83% of days. Sticky, muggy-or-worse air turns up on roughly 85% of them.

0%25%50%75%100%151015202531
Humid (%)Muggy (%)Oppressive (%)
123752
222762
321772
420782
519792
619792
718802
818802
917812
1017812
1116822
1216822
1316822
1416822
1515832
1615832
1715832
1814842
1913852
2013852
2112862
2212862
2311872
2411872
2510882
2610882
2710882
2810882
299892
309892
319892

Wind in March

Winds average 5 km/h in March.

Across March, daily wind ranges from about 4 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
214calm
224calm
234calm
244calm
254calm
264calm
274calm
284calm
294calm
304calm
314calm

Sunrise & sunset in March

DaylightNight

Daylight runs from about 11 h 48 min at the start of March to 12 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over March. Sunrise moves from 5:54 AM to 5:38 AM, and sunset from 5:42 PM to 5:42 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
111.85:545:42
211.85:535:42
311.85:535:42
411.85:535:42
511.85:525:42
611.85:525:42
711.95:515:43
811.95:515:43
911.95:505:43
1011.95:505:43
1111.95:495:43
1211.95:495:43
1311.95:485:43
1411.95:475:43
1511.95:475:43
1611.95:465:43
1711.95:465:42
1812.05:455:42
1912.05:455:42
2012.05:445:42
2112.05:445:42
2212.05:435:42
2312.05:425:42
2412.05:425:42
2512.05:415:42
2612.05:415:42
2712.05:405:42
2812.05:395:42
2912.15:395:42
3012.15:385:42
3112.15:385:42

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 6.24 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 3.71 kWh/m² to a high of 6.24 kWh/m² in March across the year — March's 6.24 kWh/m² sits near the top of that range.

0246151015202531
Solar energy (kWh/m²)Level
16.2Intense
26.2Intense
36.2Intense
46.2Intense
56.2Intense
66.2Intense
76.3Intense
86.3Intense
96.3Intense
106.3Intense
116.3Intense
126.3Intense
136.3Intense
146.3Intense
156.3Intense
166.3Intense
176.3Intense
186.3Intense
196.2Intense
206.2Intense
216.2Intense
226.2Intense
236.2Intense
246.2Intense
256.2Intense
266.2Intense
276.2Intense
286.2Intense
296.1Intense
306.1Intense
316.1Intense
Planning a trip in March

Hazard calendar for San Isidro

In seasonPeak

None of San Isidro's seasonal hazards are active in March. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

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

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

Is March a good time to visit San Isidro?

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

4.7
Sightseeing
3rd-best month of the year
4.1
Beach & pool
2nd-best month of the year

March is a reasonable time to visit San Isidro for sightseeing.

What to pack for San Isidro in March

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

In March, San Isidro sees daytime highs around 25°C and nights near 21°C. Pack rain gear and sun protection. Worth having: light clothes. About 26 days see rain.

rain gearsun protectionlight clothes

Sea temperature near San Isidro in March

The nearest coast averages about 30°C in March — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 28 km away) is warmest in March at about 30°C and coldest in November near 28°C.

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

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb30Tropical
Mar30Tropical
Apr30Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct28Tropical
Nov28Warm
Dec28Tropical

UV index in San Isidro in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 15 (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 Isidro peaks around March 16 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 10 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 16UV 14Dec 16UV 10
UV index (midday)Level
Jan12Extreme
Feb14Extreme
Mar15Extreme
Apr14Extreme
May13Extreme
Jun13Extreme
Jul12Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov12Extreme
Dec10Extreme
Location & terrain

Where is San Isidro?

San Isidro sits at 9.4°N, 83.7°W, 713 m above sea level, in Costa Rica. The nearest listed city is Manuel Antonio, 51 km away.

Manuel AntonioParaísoTurrialbaCartagoSan DiegoPatarráSan MiguelAserrí

Topography around San Isidro

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

Within 3 km, the terrain around San Isidro has only modest variations in elevation — a maximum elevation change of 211 m around an average of 723 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 2,363 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,764 m.

The land around San Isidro is covered by trees (40%), grassland (31%) and artificial surfaces (28%) within 3 km, trees (71%) and grassland (27%) within 16 km, and trees (67%) and water (22%) within 80 km.

3 km
211 m
16 km
2,363 m
80 km
3,764 m
treesgrasslandartificial surfaceswatermangroves
March weather nearby: Manuel Antonio 51 km · Paraíso 56 km · Turrialba 60 km · Cartago 60 km · San Diego 68 km · Patarrá 68 km · San Miguel 69 km · Aserrí 70 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 Isidro (9.3674°, -83.6971°, elevation 713 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).