Puerto Viejo weather in September

In September, Puerto Viejo sees average daytime highs of 28°C and overnight lows near 26°C, with 273 mm of rain across 27.2 wet days and about 12.1 hours of daylight. It is the 1st-warmest and 9th-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 3% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 h 12 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Puerto Viejo's 8th-clearest and 12th-windiest month. For the whole year in context, see Puerto Viejo's year-round climate.

Daytime high: 28°; 1st warmest
Overnight low: 26°; 11th coldest
Rainfall: 273 mm; 27.2 wet days
Daylight: 12 h 06 min; 5:24 AM – 5:27 PM
Cloud cover: 85%; 8th clearest
Wind: 6 km/h; 12th windiest
Solar energy: 4.86 kWh/m²
Travel score: 3.5; out of 10

← August Puerto Viejo year-round climate October →Best places to visit in September

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical September day in Puerto Viejo reaches about 28°C in the afternoon and slips back to 26°C overnight — a 2°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, September runs on par with August and on par with October.

	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)	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28	28
Avg low (°C)	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26	26

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

Puerto Viejo weather by month

How September compares with the rest of the year at a glance. September is the 1st-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	27° / 24°	301	21.9	11.5	5.0
Feb	27° / 24°	184	18.4	11.7	5.3
Mar	27° / 25°	158	19.2	11.9	5.3
Apr	28° / 25°	206	21.2	12.2	4.6
May	28° / 26°	388	27	12.4	3.7
Jun	28° / 26°	446	28.3	12.6	3.3
Jul	28° / 25°	581	30.3	12.5	3.3
Aug	28° / 26°	415	29	12.3	3.4
Sep	28° / 26°	273	27.2	12.1	3.5
Oct	28° / 26°	322	28	11.8	3.6
Nov	27° / 25°	581	27.4	11.6	3.7
Dec	27° / 25°	480	26.4	11.4	4.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 3% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 7% of September, with mostly cloudy or overcast conditions the remaining 89%.

	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 (%)	11	11	11	11	11	11	12	11	11	11	11	11	11	11	11	10	10	10	10	10	11	11	11	11	10	10	10	10	10	10
Cloudier (%)	89	89	89	89	89	89	88	89	89	89	89	89	89	89	89	90	90	90	90	90	89	89	89	89	90	90	90	90	90	90

	Clearer (%)	Cloudier (%)
1	11	89
2	11	89
3	11	89
4	11	89
5	11	89
6	11	89
7	12	88
8	11	89
9	11	89
10	11	89
11	11	89
12	11	89
13	11	89
14	11	89
15	11	89
16	10	90
17	10	90
18	10	90
19	10	90
20	10	90
21	11	89
22	11	89
23	11	89
24	11	89
25	10	90
26	10	90
27	10	90
28	10	90
29	10	90
30	10	90

Chance of precipitation in September

Any precipitation

Puerto Viejo gets around 273 mm of rain over 27.2 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 90% and peaks near 91% on the wettest days.

	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 (%)	89	90	90	90	90	91	91	91	91	91	91	91	90	90	90	90	90	90	90	90	90	90	90	90	90	90	90	90	90	90

	Rain chance (%)
1	89
2	90
3	90
4	90
5	90
6	91
7	91
8	91
9	91
10	91
11	91
12	91
13	90
14	90
15	90
16	90
17	90
18	90
19	90
20	90
21	90
22	90
23	90
24	90
25	90
26	90
27	90
28	90
29	90
30	90

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 90% of days. Sticky, muggy-or-worse air turns up on roughly 100% 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
Oppressive (%)	92	92	92	92	92	92	92	92	92	92	92	91	91	90	90	90	89	89	88	88	88	88	88	88	89	89	90	90	91	91
Miserable (%)	8	8	8	8	8	8	8	8	8	8	8	9	9	10	10	10	11	11	12	12	12	12	12	12	11	11	10	10	9	9

	Oppressive (%)	Miserable (%)
1	92	8
2	92	8
3	92	8
4	92	8
5	92	8
6	92	8
7	92	8
8	92	8
9	92	8
10	92	8
11	92	8
12	91	9
13	91	9
14	90	10
15	90	10
16	90	10
17	89	11
18	89	11
19	88	12
20	88	12
21	88	12
22	88	12
23	88	12
24	88	12
25	89	11
26	89	11
27	90	10
28	90	10
29	91	9
30	91	9

Wind in September

Winds average 6 km/h in September, the calmest month.

Across September, daily wind ranges from about 6 km/h on the calmest days to 7 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)	7	7	7	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6	6
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	7	calm
2	7	calm
3	7	calm
4	6	calm
5	6	calm
6	6	calm
7	6	calm
8	6	calm
9	6	calm
10	6	calm
11	6	calm
12	6	calm
13	6	calm
14	6	calm
15	6	calm
16	6	calm
17	6	calm
18	6	calm
19	6	calm
20	6	calm
21	6	calm
22	6	calm
23	6	calm
24	6	calm
25	6	calm
26	6	calm
27	6	calm
28	6	calm
29	6	calm
30	6	calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 12 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 18 minutes over September. Sunrise moves from 5:25 AM to 5:23 AM, and sunset from 5:36 PM to 5:18 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)	12.2	12.2	12.2	12.2	12.2	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.1	12.0	12.0	12.0	12.0	12.0	12.0	12.0	12.0	12.0	12.0	12.0	11.9	11.9	11.9
Sunrise (AM)	5:25	5:25	5:25	5:25	5:25	5:25	5:25	5:25	5:24	5:24	5:24	5:24	5:24	5:24	5:24	5:24	5:24	5:24	5:23	5:23	5:23	5:23	5:23	5:23	5:23	5:23	5:23	5:23	5:23	5:23
Sunset (PM)	5:36	5:36	5:35	5:35	5:34	5:33	5:33	5:32	5:31	5:31	5:30	5:29	5:29	5:28	5:28	5:27	5:26	5:26	5:25	5:24	5:24	5:23	5:22	5:22	5:21	5:21	5:20	5:19	5:19	5:18

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	12.2	5:25	5:36
2	12.2	5:25	5:36
3	12.2	5:25	5:35
4	12.2	5:25	5:35
5	12.2	5:25	5:34
6	12.1	5:25	5:33
7	12.1	5:25	5:33
8	12.1	5:25	5:32
9	12.1	5:24	5:31
10	12.1	5:24	5:31
11	12.1	5:24	5:30
12	12.1	5:24	5:29
13	12.1	5:24	5:29
14	12.1	5:24	5:28
15	12.1	5:24	5:28
16	12.1	5:24	5:27
17	12.0	5:24	5:26
18	12.0	5:24	5:26
19	12.0	5:23	5:25
20	12.0	5:23	5:24
21	12.0	5:23	5:24
22	12.0	5:23	5:23
23	12.0	5:23	5:22
24	12.0	5:23	5:22
25	12.0	5:23	5:21
26	12.0	5:23	5:21
27	12.0	5:23	5:20
28	11.9	5:23	5:19
29	11.9	5:23	5:19
30	11.9	5:23	5:18

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.86 kWh/m².

For context, solar energy here swings from a low near 3.73 kWh/m² to a high of 5.6 kWh/m² in March across the year — September's 4.86 kWh/m² falls in the middle.

	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)	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.9	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.8	4.7	4.7	4.7
Level	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	Bright	Bright	Bright	Bright	Bright

	Solar energy (kWh/m²)	Level
1	4.9	Bright
2	4.9	Bright
3	4.9	Bright
4	4.9	Bright
5	4.9	Bright
6	4.9	Bright
7	4.9	Bright
8	4.9	Bright
9	4.9	Bright
10	4.9	Bright
11	4.9	Bright
12	4.9	Bright
13	4.9	Bright
14	4.9	Bright
15	4.9	Bright
16	4.9	Bright
17	4.8	Bright
18	4.8	Bright
19	4.8	Bright
20	4.8	Bright
21	4.8	Bright
22	4.8	Bright
23	4.8	Bright
24	4.8	Bright
25	4.8	Bright
26	4.8	Bright
27	4.8	Bright
28	4.7	Bright
29	4.7	Bright
30	4.7	Bright

Planning a trip in September

Is September a good time to visit Puerto Viejo?

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

3.5

Sightseeing

9th-best month of the year

3.9

Beach & pool

7th-best month of the year

September is a weaker month for outdoor sightseeing in Puerto Viejo.

What to pack for Puerto Viejo in September

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

In September, Puerto Viejo sees daytime highs around 28°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 27 days see rain.

light clothesrain gearsun protection

Sea temperature near Puerto Viejo in September

The nearest coast averages about 29°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 15 km away) is warmest in September at about 29°C and coldest in January near 27°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)	27	27	28	28	29	29	28	29	29	29	28	28
Comfort	Warm	Warm	Warm	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Tropical	Warm

	Sea temperature (°C)	Comfort
Jan	27	Warm
Feb	27	Warm
Mar	28	Warm
Apr	28	Tropical
May	29	Tropical
Jun	29	Tropical
Jul	28	Tropical
Aug	29	Tropical
Sep	29	Tropical
Oct	29	Tropical
Nov	28	Tropical
Dec	28	Warm

UV index in Puerto Viejo in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September 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 Puerto Viejo peaks around March 19 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 16 at about 10 (very high).

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)	11	13	14	13	13	13	12	12	12	12	11	10
Level	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Very high

	UV index (midday)	Level
Jan	11	Extreme
Feb	13	Extreme
Mar	14	Extreme
Apr	13	Extreme
May	13	Extreme
Jun	13	Extreme
Jul	12	Extreme
Aug	12	Extreme
Sep	12	Extreme
Oct	12	Extreme
Nov	11	Extreme
Dec	10	Very high

Air quality in Puerto Viejo in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Puerto Viejo is worst in July — around 18 µg/m³ PM2.5 (moderate), about 2.8× the cleanest month (November, 6 µg/m³).

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

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
PM2.5 (µg/m³)	7	9	9	13	17	16	18	15	11	10	6	7
Level	Good	Good	Good	Moderate	Moderate	Moderate	Moderate	Moderate	Good	Good	Good	Good

	PM2.5 (µg/m³)	Level
Jan	7	Good
Feb	9	Good
Mar	9	Good
Apr	13	Moderate
May	17	Moderate
Jun	16	Moderate
Jul	18	Moderate
Aug	15	Moderate
Sep	11	Good
Oct	10	Good
Nov	6	Good
Dec	7	Good

Location & terrain

Where is Puerto Viejo?

Puerto Viejo sits at 9.7°N, 82.8°W, 0 m above sea level, in Costa Rica. The nearest listed city is Changuinola, 36 km away.

Topography around Puerto Viejo

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

Within 3 km, the terrain around Puerto Viejo has only modest variations in elevation — a maximum elevation change of 206 m around an average of 29 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 884 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,593 m.

The land around Puerto Viejo is covered by water (52%) and trees (46%) within 3 km, trees (54%) and water (43%) within 16 km, and trees (63%) and water (35%) within 80 km.

3 km

206 m

water 52%

16 km

884 m

trees 54%

80 km

3,593 m

trees 63%

treesgrasslandartificial surfaceswater

← August Puerto Viejo year-round climate October →Best places to visit in September

September weather nearby: Changuinola 36 km · Puerto Limón 48 km · Bocas del Toro 66 km · Siquirres 96 km · Boquete 103 km · Turrialba 105 km · San Isidro 108 km · Paraíso 124 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 Puerto Viejo (9.6569°, -82.7545°, elevation 0 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).

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

	Clearer (%)	Cloudier (%)
1	11	89
2	11	89
3	11	89
4	11	89
5	11	89
6	11	89
7	12	88
8	11	89
9	11	89
10	11	89
11	11	89
12	11	89
13	11	89
14	11	89
15	11	89
16	10	90
17	10	90
18	10	90
19	10	90
20	10	90
21	11	89
22	11	89
23	11	89
24	11	89
25	10	90
26	10	90
27	10	90
28	10	90
29	10	90
30	10	90

	Rain chance (%)
1	89
2	90
3	90
4	90
5	90
6	91
7	91
8	91
9	91
10	91
11	91
12	91
13	90
14	90
15	90
16	90
17	90
18	90
19	90
20	90
21	90
22	90
23	90
24	90
25	90
26	90
27	90
28	90
29	90
30	90

	Oppressive (%)	Miserable (%)
1	92	8
2	92	8
3	92	8
4	92	8
5	92	8
6	92	8
7	92	8
8	92	8
9	92	8
10	92	8
11	92	8
12	91	9
13	91	9
14	90	10
15	90	10
16	90	10
17	89	11
18	89	11
19	88	12
20	88	12
21	88	12
22	88	12
23	88	12
24	88	12
25	89	11
26	89	11
27	90	10
28	90	10
29	91	9
30	91	9

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

	Clearer (%)	Cloudier (%)
1	11	89
2	11	89
3	11	89
4	11	89
5	11	89
6	11	89
7	12	88
8	11	89
9	11	89
10	11	89
11	11	89
12	11	89
13	11	89
14	11	89
15	11	89
16	10	90
17	10	90
18	10	90
19	10	90
20	10	90
21	11	89
22	11	89
23	11	89
24	11	89
25	10	90
26	10	90
27	10	90
28	10	90
29	10	90
30	10	90

	Rain chance (%)
1	89
2	90
3	90
4	90
5	90
6	91
7	91
8	91
9	91
10	91
11	91
12	91
13	90
14	90
15	90
16	90
17	90
18	90
19	90
20	90
21	90
22	90
23	90
24	90
25	90
26	90
27	90
28	90
29	90
30	90

	Oppressive (%)	Miserable (%)
1	92	8
2	92	8
3	92	8
4	92	8
5	92	8
6	92	8
7	92	8
8	92	8
9	92	8
10	92	8
11	92	8
12	91	9
13	91	9
14	90	10
15	90	10
16	90	10
17	89	11
18	89	11
19	88	12
20	88	12
21	88	12
22	88	12
23	88	12
24	88	12
25	89	11
26	89	11
27	90	10
28	90	10
29	91	9
30	91	9

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

	Clearer (%)	Cloudier (%)
1	11	89
2	11	89
3	11	89
4	11	89
5	11	89
6	11	89
7	12	88
8	11	89
9	11	89
10	11	89
11	11	89
12	11	89
13	11	89
14	11	89
15	11	89
16	10	90
17	10	90
18	10	90
19	10	90
20	10	90
21	11	89
22	11	89
23	11	89
24	11	89
25	10	90
26	10	90
27	10	90
28	10	90
29	10	90
30	10	90

	Rain chance (%)
1	89
2	90
3	90
4	90
5	90
6	91
7	91
8	91
9	91
10	91
11	91
12	91
13	90
14	90
15	90
16	90
17	90
18	90
19	90
20	90
21	90
22	90
23	90
24	90
25	90
26	90
27	90
28	90
29	90
30	90

	Oppressive (%)	Miserable (%)
1	92	8
2	92	8
3	92	8
4	92	8
5	92	8
6	92	8
7	92	8
8	92	8
9	92	8
10	92	8
11	92	8
12	91	9
13	91	9
14	90	10
15	90	10
16	90	10
17	89	11
18	89	11
19	88	12
20	88	12
21	88	12
22	88	12
23	88	12
24	88	12
25	89	11
26	89	11
27	90	10
28	90	10
29	91	9
30	91	9