Puntarenas weather in September

In September, Puntarenas sees average daytime highs of 28°C and overnight lows near 23°C, with 409 mm of rain across 29.8 wet days and about 12.1 hours of daylight. It is the 10th-warmest and 5th-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 0% 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 Puntarenas's 11th-clearest and 8th-windiest month. For the whole year in context, see Puntarenas's year-round climate.

Daytime high
28°
10th warmest
Overnight low
23°
6th coldest
Rainfall
409 mm
29.8 wet days
Daylight
12 h 06 min
5:32 AM – 5:35 PM
Cloud cover
90%
11th clearest
Wind
5 km/h
8th windiest
Solar energy
4.42 kWh/m²
Travel score
3.2
out of 10

Puntarenas is city in Costa Rica.

Density
751/km²
people per km²
Founded
1858

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

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 Puntarenas reaches about 28°C in the afternoon and slips back to 23°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 29°C. Set against its neighbours, September runs on par with August and on par with October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12823
22823
32823
42823
52823
62823
72823
82823
92823
102823
112823
122823
132823
142823
152823
162823
172823
182823
192823
202823
212823
222823
232823
242823
252823
262823
272723
282723
292723
302723

How September really feels in Puntarenas

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Puntarenas weather by month

How September compares with the rest of the year at a glance. September is the 10th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 23°24811.55.9
Feb31° / 23°164.511.75.7
Mar31° / 23°309.711.94.9
Apr30° / 24°12222.512.23.7
May28° / 24°41229.912.53.1
Jun28° / 24°41229.712.63.0
Jul28° / 24°36930.512.53.2
Aug28° / 23°41430.712.33.2
Sep28° / 23°40929.812.13.2
Oct27° / 23°47930.611.83.2
Nov28° / 23°28227.211.53.7
Dec28° / 23°8217.611.45.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 0% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 2% of September, with mostly cloudy or overcast conditions the remaining 98%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1298
2298
3298
4298
5298
6298
7298
8298
9298
10298
11298
12298
13298
14298
15298
16298
17298
18298
19298
20298
21298
22298
23298
24298
25298
26298
27298
28298
29298
30199

Chance of precipitation in September

Any precipitation

Puntarenas gets around 409 mm of rain over 29.8 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 100% and peaks near 100% on the wettest days.

0%20%40%60%80%100%151015202530
Rain chance (%)
1100
2100
3100
4100
5100
6100
7100
8100
9100
10100
11100
12100
13100
14100
15100
16100
1799
1899
1999
2099
2199
2299
2399
2499
2599
2699
2799
2899
2999
3099

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

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)
10100
20100
30100
40100
50100
60100
70100
80100
90100
100100
110100
120100
130100
140100
150100
160100
170100
180100
190100
200100
210100
220100
230100
24199
25199
26199
27199
28199
29199
30199

Wind in September

Winds average 5 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 5 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
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
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

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 5:33 AM to 5:31 AM, and sunset from 5:45 PM to 5:26 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.25:335:45
212.25:335:44
312.25:335:44
412.25:335:43
512.25:335:42
612.15:335:42
712.15:335:41
812.15:335:41
912.15:335:40
1012.15:335:39
1112.15:325:39
1212.15:325:38
1312.15:325:37
1412.15:325:37
1512.15:325:36
1612.15:325:35
1712.05:325:35
1812.05:325:34
1912.05:325:33
2012.05:325:33
2112.05:325:32
2212.05:325:31
2312.05:315:31
2412.05:315:30
2512.05:315:29
2612.05:315:29
2712.05:315:28
2811.95:315:28
2911.95:315:27
3011.95:315:26

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.42 kWh/m².

For context, solar energy here swings from a low near 4 kWh/m² to a high of 6.47 kWh/m² in March across the year — September's 4.42 kWh/m² sits near the bottom.

024151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.6Bright
54.5Bright
64.5Bright
74.5Bright
84.5Bright
94.5Bright
104.5Bright
114.5Bright
124.5Bright
134.4Bright
144.4Bright
154.4Bright
164.4Bright
174.4Bright
184.4Bright
194.4Bright
204.3Bright
214.3Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.3Bright
274.3Bright
284.3Bright
294.3Bright
304.2Bright
Planning a trip in September

Hazard calendar for Puntarenas

In seasonPeak

In September, Puntarenas sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Puntarenas'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 September a good time to visit Puntarenas?

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

3.2
Sightseeing
7th-best month of the year
3.4
Beach & pool
12th-best month of the year

September is a weaker month for outdoor sightseeing in Puntarenas.

What to pack for Puntarenas in September

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

In September, Puntarenas sees daytime highs around 28°C and nights near 23°C. Pack light clothes and rain gear. About 30 days see rain.

light clothesrain gear

Sea temperature near Puntarenas 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 26 km away) is warmest in April at about 29°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°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct28Tropical
Nov28Warm
Dec28Tropical

UV index in Puntarenas 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 Puntarenas peaks around March 12 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 17 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highMar 12UV 13Dec 17UV 10
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun13Extreme
Jul12Extreme
Aug12Extreme
Sep12Extreme
Oct11Extreme
Nov11Extreme
Dec9Very high

Air quality in Puntarenas 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 Puntarenas is worst in May — around 18 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (January, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMay 1617 µg/m³Jan 19 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar11Good
Apr16Moderate
May18Moderate
Jun16Moderate
Jul17Moderate
Aug15Moderate
Sep14Moderate
Oct12Moderate
Nov11Good
Dec9Good
Location & terrain

Where is Puntarenas?

Puntarenas sits at 10.0°N, 84.8°W, 1 m above sea level, in Costa Rica. The nearest listed city is Chacarita, 7.0 km away.

MonteverdeSan_Ramon_JacoCañasLa FortunaQuesada

Topography around Puntarenas

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

Within 3 km, the terrain around Puntarenas has only modest variations in elevation — a maximum elevation change of 27 m around an average of 3 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 413 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,692 m.

The land around Puntarenas is covered by water (74%) within 3 km, water (53%) and trees (21%) within 16 km, and trees (49%) and water (30%) within 80 km.

3 km
27 m
16 km
413 m
80 km
2,692 m
treesgrasslandcroplandartificial surfaceswatermangroves
September weather nearby: Chacarita 7.0 km · Esparza 19 km · Monteverde 37 km · San_Ramon_ 42 km · Jaco 46 km · Cañas 58 km · La Fortuna 59 km · Quesada 59 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 Puntarenas (9.9769°, -84.8379°, elevation 1 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).