San Isidro weather in April

In April, San Isidro sees average daytime highs of 25°C and overnight lows near 21°C, with 330 mm of rain across 28.6 wet days and about 12.2 hours of daylight. It is the 2nd-warmest and 9th-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 12% of the time in April, and the air most often feels muggy.

Daylight stretches from about 12 h 06 min at the start of April to 12 h 18 min by month's end. Set against the rest of the year, April is San Isidro's 5th-clearest and 12th-windiest month. For the whole year in context, see San Isidro's year-round climate.

Daytime high: 25°; 2nd warmest
Overnight low: 21°; 10th coldest
Rainfall: 330 mm; 28.6 wet days
Daylight: 12 h 12 min; 5:29 AM – 5:41 PM
Cloud cover: 73%; 5th clearest
Wind: 4 km/h; 12th windiest
Solar energy: 5.64 kWh/m²
Travel score: 3.8; 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.

← March San Isidro year-round climate May →Best places to visit in April

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

Temperature in April

Average highAverage lowShaded bands: 10–90% of days

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

A typical April 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 25°C. Set against its neighbours, April runs on par with March and on par with May.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Avg high (°C)	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	25	24	24	24	24	24
Avg low (°C)	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21

	Avg high (°C)	Avg low (°C)
1	25	21
2	25	21
3	25	21
4	25	21
5	25	21
6	25	21
7	25	21
8	25	21
9	25	21
10	25	21
11	25	21
12	25	21
13	25	21
14	25	21
15	25	21
16	25	21
17	25	21
18	25	21
19	25	21
20	25	21
21	25	21
22	25	21
23	25	21
24	25	21
25	25	21
26	24	21
27	24	21
28	24	21
29	24	21
30	24	21

San Isidro weather by month

How April compares with the rest of the year at a glance. April is the 2nd-warmest and 9th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	24° / 20°	210	25.2	11.5	4.8
Feb	24° / 20°	140	21.6	11.7	5.1
Mar	25° / 21°	138	25.6	11.9	4.7
Apr	25° / 21°	330	28.6	12.2	3.8
May	24° / 21°	730	30.8	12.4	3.4
Jun	24° / 21°	709	29.9	12.5	3.4
Jul	24° / 21°	833	31	12.5	3.4
Aug	24° / 21°	933	31	12.3	3.4
Sep	24° / 21°	808	30	12.1	3.4
Oct	24° / 20°	952	30.8	11.8	3.4
Nov	24° / 20°	924	29.9	11.6	3.5
Dec	24° / 20°	413	28.8	11.5	4.1

Cloud cover in April

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 12% of the time in April.

Beyond those clear spells, partly cloudy skies cover about 20% of April, with mostly cloudy or overcast conditions the remaining 68%. Skies tend to cloud over as the month goes on.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Clearer (%)	52	50	49	47	45	44	42	41	41	39	38	36	35	34	33	32	32	29	29	28	26	25	23	22	20	19	17	15	15	13
Cloudier (%)	48	50	51	53	55	56	58	59	59	61	62	64	65	66	67	68	68	71	71	72	74	75	77	78	80	81	83	85	85	87

	Clearer (%)	Cloudier (%)
1	52	48
2	50	50
3	49	51
4	47	53
5	45	55
6	44	56
7	42	58
8	41	59
9	41	59
10	39	61
11	38	62
12	36	64
13	35	65
14	34	66
15	33	67
16	32	68
17	32	68
18	29	71
19	29	71
20	28	72
21	26	74
22	25	75
23	23	77
24	22	78
25	20	80
26	19	81
27	17	83
28	15	85
29	15	85
30	13	87

Chance of precipitation in April

Any precipitation

San Isidro gets around 330 mm of rain over 28.6 wet days in April. 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 99% on the wettest days. The odds climb toward the end of the month.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Rain chance (%)	91	91	91	92	92	92	92	92	93	93	93	94	94	95	95	96	96	97	97	97	98	98	98	98	98	98	99	99	99	99

	Rain chance (%)
1	91
2	91
3	91
4	92
5	92
6	92
7	92
8	92
9	93
10	93
11	93
12	94
13	94
14	95
15	95
16	96
17	96
18	97
19	97
20	97
21	98
22	98
23	98
24	98
25	98
26	98
27	99
28	99
29	99
30	99

Humidity in April

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, April lands in the muggy band about 93% of days. Sticky, muggy-or-worse air turns up on roughly 96% of them.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Humid (%)	9	9	9	8	8	8	7	7	6	6	5	5	4	4	3	3	2	2	2	1	1	1	1	1	1	1	0	0	0	0
Muggy (%)	89	89	89	90	90	90	91	91	92	92	93	93	94	94	95	95	96	95	95	95	95	94	94	94	93	93	94	93	93	93
Oppressive (%)	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	2	3	3	4	4	5	5	5	6	6	6	7	7	7

	Humid (%)	Muggy (%)	Oppressive (%)
1	9	89	2
2	9	89	2
3	9	89	2
4	8	90	2
5	8	90	2
6	8	90	2
7	7	91	2
8	7	91	2
9	6	92	2
10	6	92	2
11	5	93	2
12	5	93	2
13	4	94	2
14	4	94	2
15	3	95	2
16	3	95	2
17	2	96	2
18	2	95	3
19	2	95	3
20	1	95	4
21	1	95	4
22	1	94	5
23	1	94	5
24	1	94	5
25	1	93	6
26	1	93	6
27	0	94	6
28	0	93	7
29	0	93	7
30	0	93	7

Wind in April

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

Across April, 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.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Wind speed (km/h)	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4	4
Feels	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm	calm

	Wind speed (km/h)	Feels
1	4	calm
2	4	calm
3	4	calm
4	4	calm
5	4	calm
6	4	calm
7	4	calm
8	4	calm
9	4	calm
10	4	calm
11	4	calm
12	4	calm
13	4	calm
14	4	calm
15	4	calm
16	4	calm
17	4	calm
18	4	calm
19	4	calm
20	4	calm
21	4	calm
22	4	calm
23	4	calm
24	4	calm
25	4	calm
26	4	calm
27	4	calm
28	4	calm
29	4	calm
30	4	calm

Sunrise & sunset in April

DaylightNight

Daylight runs from about 12 h 06 min at the start of April to 12 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 12 minutes over April. Sunrise moves from 5:37 AM to 5:23 AM, and sunset from 5:42 PM to 5:42 PM.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Daylight (h)	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.2	12.3	12.3	12.3	12.3	12.3	12.3	12.3	12.3	12.3
Sunrise (AM)	5:37	5:37	5:36	5:35	5:35	5:34	5:34	5:33	5:33	5:32	5:31	5:31	5:30	5:30	5:29	5:29	5:28	5:28	5:27	5:27	5:26	5:26	5:25	5:25	5:25	5:24	5:24	5:23	5:23	5:23
Sunset (PM)	5:42	5:42	5:42	5:42	5:42	5:42	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:41	5:42	5:42	5:42

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	12.1	5:37	5:42
2	12.1	5:37	5:42
3	12.1	5:36	5:42
4	12.1	5:35	5:42
5	12.1	5:35	5:42
6	12.1	5:34	5:42
7	12.1	5:34	5:41
8	12.1	5:33	5:41
9	12.1	5:33	5:41
10	12.2	5:32	5:41
11	12.2	5:31	5:41
12	12.2	5:31	5:41
13	12.2	5:30	5:41
14	12.2	5:30	5:41
15	12.2	5:29	5:41
16	12.2	5:29	5:41
17	12.2	5:28	5:41
18	12.2	5:28	5:41
19	12.2	5:27	5:41
20	12.2	5:27	5:41
21	12.2	5:26	5:41
22	12.3	5:26	5:41
23	12.3	5:25	5:41
24	12.3	5:25	5:41
25	12.3	5:25	5:41
26	12.3	5:24	5:41
27	12.3	5:24	5:41
28	12.3	5:23	5:42
29	12.3	5:23	5:42
30	12.3	5:23	5:42

Solar energy in April

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in April, about 5.64 kWh/m².

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 — April's 5.64 kWh/m² sits near the top of that range.

	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30
Solar energy (kWh/m²)	6.1	6.1	6.0	6.0	6.0	6.0	6.0	5.9	5.9	5.9	5.8	5.8	5.8	5.7	5.7	5.7	5.6	5.6	5.5	5.5	5.5	5.4	5.4	5.3	5.3	5.2	5.2	5.1	5.1	5.0
Level	Intense	Intense	Intense	Intense	Intense	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	6.1	Intense
2	6.1	Intense
3	6.0	Intense
4	6.0	Intense
5	6.0	Intense
6	6.0	Bright
7	6.0	Bright
8	5.9	Bright
9	5.9	Bright
10	5.9	Bright
11	5.8	Bright
12	5.8	Bright
13	5.8	Bright
14	5.7	Bright
15	5.7	Bright
16	5.7	Bright
17	5.6	Bright
18	5.6	Bright
19	5.5	Bright
20	5.5	Bright
21	5.5	Bright
22	5.4	Bright
23	5.4	Bright
24	5.3	Bright
25	5.3	Bright
26	5.2	Bright
27	5.2	Bright
28	5.1	Bright
29	5.1	Bright
30	5.0	Bright

Planning a trip in April

Hazard calendar for San Isidro

In seasonPeak

None of San Isidro's seasonal hazards are active in April. 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 April a good time to visit San Isidro?

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

3.8

Sightseeing

5th-best month of the year

3.4

Beach & pool

4th-best month of the year

April is a weaker month for outdoor sightseeing in San Isidro.

What to pack for San Isidro in April

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

In April, San Isidro sees daytime highs around 25°C and nights near 21°C. Pack rain gear. Worth having: light clothes and sun protection. About 29 days see rain.

rain gearlight clothessun protection

Sea temperature near San Isidro in April

The nearest coast averages about 30°C in April — 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.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Sea temperature (°C)	29	30	30	30	29	29	29	29	29	28	28	28
Comfort	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Warm	Tropical

	Sea temperature (°C)	Comfort
Jan	29	Tropical
Feb	30	Tropical
Mar	30	Tropical
Apr	30	Tropical
May	29	Tropical
Jun	29	Tropical
Jul	29	Tropical
Aug	29	Tropical
Sep	29	Tropical
Oct	28	Tropical
Nov	28	Warm
Dec	28	Tropical

UV index in San Isidro in April

LowModerateHighVery highExtreme

Clear-sky midday UV in April peaks around 14 (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.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	12	14	15	14	13	13	12	13	13	12	12	10
Level	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme

	UV index (midday)	Level
Jan	12	Extreme
Feb	14	Extreme
Mar	15	Extreme
Apr	14	Extreme
May	13	Extreme
Jun	13	Extreme
Jul	12	Extreme
Aug	13	Extreme
Sep	13	Extreme
Oct	12	Extreme
Nov	12	Extreme
Dec	10	Extreme

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.

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

trees 40%

16 km

2,363 m

trees 71%

80 km

3,764 m

trees 67%

treesgrasslandartificial surfaceswatermangroves

← March San Isidro year-round climate May →Best places to visit in April

April 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

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).

	Avg high (°C)	Avg low (°C)
1	25	21
2	25	21
3	25	21
4	25	21
5	25	21
6	25	21
7	25	21
8	25	21
9	25	21
10	25	21
11	25	21
12	25	21
13	25	21
14	25	21
15	25	21
16	25	21
17	25	21
18	25	21
19	25	21
20	25	21
21	25	21
22	25	21
23	25	21
24	25	21
25	25	21
26	24	21
27	24	21
28	24	21
29	24	21
30	24	21

	Clearer (%)	Cloudier (%)
1	52	48
2	50	50
3	49	51
4	47	53
5	45	55
6	44	56
7	42	58
8	41	59
9	41	59
10	39	61
11	38	62
12	36	64
13	35	65
14	34	66
15	33	67
16	32	68
17	32	68
18	29	71
19	29	71
20	28	72
21	26	74
22	25	75
23	23	77
24	22	78
25	20	80
26	19	81
27	17	83
28	15	85
29	15	85
30	13	87

	Rain chance (%)
1	91
2	91
3	91
4	92
5	92
6	92
7	92
8	92
9	93
10	93
11	93
12	94
13	94
14	95
15	95
16	96
17	96
18	97
19	97
20	97
21	98
22	98
23	98
24	98
25	98
26	98
27	99
28	99
29	99
30	99

	Humid (%)	Muggy (%)	Oppressive (%)
1	9	89	2
2	9	89	2
3	9	89	2
4	8	90	2
5	8	90	2
6	8	90	2
7	7	91	2
8	7	91	2
9	6	92	2
10	6	92	2
11	5	93	2
12	5	93	2
13	4	94	2
14	4	94	2
15	3	95	2
16	3	95	2
17	2	96	2
18	2	95	3
19	2	95	3
20	1	95	4
21	1	95	4
22	1	94	5
23	1	94	5
24	1	94	5
25	1	93	6
26	1	93	6
27	0	94	6
28	0	93	7
29	0	93	7
30	0	93	7

	Avg high (°C)	Avg low (°C)
1	25	21
2	25	21
3	25	21
4	25	21
5	25	21
6	25	21
7	25	21
8	25	21
9	25	21
10	25	21
11	25	21
12	25	21
13	25	21
14	25	21
15	25	21
16	25	21
17	25	21
18	25	21
19	25	21
20	25	21
21	25	21
22	25	21
23	25	21
24	25	21
25	25	21
26	24	21
27	24	21
28	24	21
29	24	21
30	24	21

	Clearer (%)	Cloudier (%)
1	52	48
2	50	50
3	49	51
4	47	53
5	45	55
6	44	56
7	42	58
8	41	59
9	41	59
10	39	61
11	38	62
12	36	64
13	35	65
14	34	66
15	33	67
16	32	68
17	32	68
18	29	71
19	29	71
20	28	72
21	26	74
22	25	75
23	23	77
24	22	78
25	20	80
26	19	81
27	17	83
28	15	85
29	15	85
30	13	87

	Rain chance (%)
1	91
2	91
3	91
4	92
5	92
6	92
7	92
8	92
9	93
10	93
11	93
12	94
13	94
14	95
15	95
16	96
17	96
18	97
19	97
20	97
21	98
22	98
23	98
24	98
25	98
26	98
27	99
28	99
29	99
30	99

	Humid (%)	Muggy (%)	Oppressive (%)
1	9	89	2
2	9	89	2
3	9	89	2
4	8	90	2
5	8	90	2
6	8	90	2
7	7	91	2
8	7	91	2
9	6	92	2
10	6	92	2
11	5	93	2
12	5	93	2
13	4	94	2
14	4	94	2
15	3	95	2
16	3	95	2
17	2	96	2
18	2	95	3
19	2	95	3
20	1	95	4
21	1	95	4
22	1	94	5
23	1	94	5
24	1	94	5
25	1	93	6
26	1	93	6
27	0	94	6
28	0	93	7
29	0	93	7
30	0	93	7

	Avg high (°C)	Avg low (°C)
1	25	21
2	25	21
3	25	21
4	25	21
5	25	21
6	25	21
7	25	21
8	25	21
9	25	21
10	25	21
11	25	21
12	25	21
13	25	21
14	25	21
15	25	21
16	25	21
17	25	21
18	25	21
19	25	21
20	25	21
21	25	21
22	25	21
23	25	21
24	25	21
25	25	21
26	24	21
27	24	21
28	24	21
29	24	21
30	24	21

	Clearer (%)	Cloudier (%)
1	52	48
2	50	50
3	49	51
4	47	53
5	45	55
6	44	56
7	42	58
8	41	59
9	41	59
10	39	61
11	38	62
12	36	64
13	35	65
14	34	66
15	33	67
16	32	68
17	32	68
18	29	71
19	29	71
20	28	72
21	26	74
22	25	75
23	23	77
24	22	78
25	20	80
26	19	81
27	17	83
28	15	85
29	15	85
30	13	87

	Rain chance (%)
1	91
2	91
3	91
4	92
5	92
6	92
7	92
8	92
9	93
10	93
11	93
12	94
13	94
14	95
15	95
16	96
17	96
18	97
19	97
20	97
21	98
22	98
23	98
24	98
25	98
26	98
27	99
28	99
29	99
30	99

	Humid (%)	Muggy (%)	Oppressive (%)
1	9	89	2
2	9	89	2
3	9	89	2
4	8	90	2
5	8	90	2
6	8	90	2
7	7	91	2
8	7	91	2
9	6	92	2
10	6	92	2
11	5	93	2
12	5	93	2
13	4	94	2
14	4	94	2
15	3	95	2
16	3	95	2
17	2	96	2
18	2	95	3
19	2	95	3
20	1	95	4
21	1	95	4
22	1	94	5
23	1	94	5
24	1	94	5
25	1	93	6
26	1	93	6
27	0	94	6
28	0	93	7
29	0	93	7
30	0	93	7