Siquirres weather in September

In September, Siquirres sees average daytime highs of 26°C and overnight lows near 20°C, with 315 mm of rain across 26.3 wet days and about 12.1 hours of daylight. It is the 1st-warmest and 4th-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 2% of the time in September, and the air most often feels muggy.

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 Siquirres's 7th-clearest and 7th-windiest month. For the whole year in context, see Siquirres's year-round climate.

Daytime high: 26°; 1st warmest
Overnight low: 20°; 9th coldest
Rainfall: 315 mm; 26.3 wet days
Daylight: 12 h 06 min; 5:27 AM – 5:30 PM
Cloud cover: 88%; 7th clearest
Wind: 4 km/h; 7th windiest
Solar energy: 4.71 kWh/m²
Travel score: 3.8; out of 10

← August Siquirres 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 26°C through the month.

A typical September day in Siquirres reaches about 26°C in the afternoon and slips back to 20°C overnight — a 7°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 28°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)	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 low (°C)	20	20	20	20	19	19	19	19	19	19	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20

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

Siquirres weather by month

How September compares with the rest of the year at a glance. September is the 1st-warmest and 4th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	24° / 17°	216	16.7	11.5	6.1
Feb	24° / 17°	151	14.4	11.7	6.2
Mar	25° / 17°	151	16.7	11.9	5.9
Apr	26° / 18°	125	17.6	12.2	5.3
May	26° / 20°	391	26.4	12.5	3.9
Jun	26° / 20°	290	27.4	12.6	3.6
Jul	26° / 20°	237	27.3	12.5	3.8
Aug	26° / 20°	222	26.9	12.3	3.9
Sep	26° / 20°	315	26.3	12.1	3.8
Oct	26° / 20°	511	27.9	11.8	3.8
Nov	25° / 19°	400	24.4	11.5	4.3
Dec	24° / 18°	286	19.3	11.4	5.4

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 2% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 6% of September, with mostly cloudy or overcast conditions the remaining 93%.

	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 (%)	8	8	8	8	8	8	8	8	8	8	6	6	7	7	7	7	8	8	8	8	7	7	7	7	7	7	7	5	5	5
Cloudier (%)	92	92	92	92	92	92	92	92	92	92	94	94	93	93	93	93	92	92	92	92	93	93	93	93	93	93	93	95	95	95

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

Chance of precipitation in September

Any precipitation

Siquirres gets around 315 mm of rain over 26.3 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 88% and peaks near 91% 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 (%)	83	83	83	83	84	84	84	85	86	86	87	87	87	88	88	88	89	89	89	90	90	90	90	91	91	91	91	91	91	91

	Rain chance (%)
1	83
2	83
3	83
4	83
5	84
6	84
7	84
8	85
9	86
10	86
11	87
12	87
13	87
14	88
15	88
16	88
17	89
18	89
19	89
20	90
21	90
22	90
23	90
24	91
25	91
26	91
27	91
28	91
29	91
30	91

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the muggy band about 92% 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
Muggy (%)	95	95	95	95	95	95	95	95	95	95	94	94	94	94	93	93	92	92	91	91	91	90	90	90	89	89	89	89	89	89
Oppressive (%)	5	5	5	5	5	5	5	5	5	5	6	6	6	6	7	7	8	8	9	9	9	10	10	10	11	11	11	11	11	11

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

Wind in September

Winds average 4 km/h in September.

Across September, 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 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 5:28 AM to 5:26 AM, and sunset from 5:40 PM to 5:21 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	11.9	11.9	11.9	11.9
Sunrise (AM)	5:28	5:28	5:28	5:28	5:28	5:28	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:27	5:26	5:26	5:26	5:26	5:26	5:26	5:26	5:26	5:26	5:26	5:26	5:26
Sunset (PM)	5:40	5:39	5:38	5:38	5:37	5:37	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	5:27	5:27	5:26	5:25	5:25	5:24	5:23	5:23	5:22	5:22	5:21

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	12.2	5:28	5:40
2	12.2	5:28	5:39
3	12.2	5:28	5:38
4	12.2	5:28	5:38
5	12.2	5:28	5:37
6	12.1	5:28	5:37
7	12.1	5:27	5:36
8	12.1	5:27	5:35
9	12.1	5:27	5:35
10	12.1	5:27	5:34
11	12.1	5:27	5:33
12	12.1	5:27	5:33
13	12.1	5:27	5:32
14	12.1	5:27	5:31
15	12.1	5:27	5:31
16	12.1	5:27	5:30
17	12.0	5:27	5:29
18	12.0	5:27	5:29
19	12.0	5:26	5:28
20	12.0	5:26	5:27
21	12.0	5:26	5:27
22	12.0	5:26	5:26
23	12.0	5:26	5:25
24	12.0	5:26	5:25
25	12.0	5:26	5:24
26	12.0	5:26	5:23
27	11.9	5:26	5:23
28	11.9	5:26	5:22
29	11.9	5:26	5:22
30	11.9	5:26	5:21

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.71 kWh/m².

For context, solar energy here swings from a low near 3.7 kWh/m² to a high of 5.76 kWh/m² in March across the year — September's 4.71 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)	4.8	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	4.7	4.7	4.7	4.7	4.7	4.7	4.6	4.6	4.6	4.6	4.6	4.6	4.5	4.5	4.5	4.5
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	4.8	Bright
2	4.8	Bright
3	4.8	Bright
4	4.8	Bright
5	4.8	Bright
6	4.8	Bright
7	4.8	Bright
8	4.8	Bright
9	4.8	Bright
10	4.8	Bright
11	4.8	Bright
12	4.7	Bright
13	4.7	Bright
14	4.7	Bright
15	4.7	Bright
16	4.7	Bright
17	4.7	Bright
18	4.7	Bright
19	4.7	Bright
20	4.7	Bright
21	4.6	Bright
22	4.6	Bright
23	4.6	Bright
24	4.6	Bright
25	4.6	Bright
26	4.6	Bright
27	4.5	Bright
28	4.5	Bright
29	4.5	Bright
30	4.5	Bright

Planning a trip in September

Is September a good time to visit Siquirres?

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

3.8

Sightseeing

9th-best month of the year

3.8

Beach & pool

9th-best month of the year

September is a weaker month for outdoor sightseeing in Siquirres.

What to pack for Siquirres in September

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

In September, Siquirres sees daytime highs around 26°C and nights near 20°C. Pack rain gear. Worth having: light clothes and sun protection. About 26 days see rain.

rain gearlight clothessun protection

Sea temperature near Siquirres 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 34 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 Siquirres in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Siquirres peaks around March 20 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 15 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	13	14	14	13	13	12	13	13	12	11	10
Level	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme	Extreme

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

Air quality in Siquirres 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 Siquirres is worst in July — around 15 µg/m³ PM2.5 (moderate), about 2.3× the cleanest month (December, 7 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	8	9	13	15	14	15	13	11	10	7	7
Level	Good	Good	Good	Moderate	Moderate	Moderate	Moderate	Moderate	Good	Good	Good	Good

	PM2.5 (µg/m³)	Level
Jan	7	Good
Feb	8	Good
Mar	9	Good
Apr	13	Moderate
May	15	Moderate
Jun	14	Moderate
Jul	15	Moderate
Aug	13	Moderate
Sep	11	Good
Oct	10	Good
Nov	7	Good
Dec	7	Good

Location & terrain

Where is Siquirres?

Siquirres sits at 10.1°N, 83.5°W, 69 m above sea level, in Costa Rica. The nearest listed city is Turrialba, 29 km away.

Topography around Siquirres

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

Within 3 km, the terrain around Siquirres has significant variations in elevation — a maximum elevation change of 486 m around an average of 137 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 1,108 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,765 m.

The land around Siquirres is covered by trees (78%) within 3 km, trees (81%) within 16 km, and trees (66%) and water (22%) within 80 km.

3 km

486 m

trees 78%

16 km

1,108 m

trees 81%

80 km

3,765 m

trees 66%

treesgrasslandcroplandartificial surfaceswater

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

September weather nearby: Turrialba 29 km · Guápiles 33 km · Paraíso 49 km · Cartago 52 km · Puerto Limón 53 km · Ipís 58 km · San Diego 58 km · Purral 60 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 Siquirres (10.0975°, -83.5066°, elevation 69 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	26	20
2	26	20
3	26	20
4	26	20
5	26	19
6	26	19
7	26	19
8	26	19
9	26	19
10	26	19
11	26	20
12	26	20
13	26	20
14	26	20
15	26	20
16	26	20
17	26	20
18	26	20
19	26	20
20	26	20
21	26	20
22	26	20
23	26	20
24	26	20
25	26	20
26	26	20
27	26	20
28	26	20
29	26	20
30	26	20

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

	Rain chance (%)
1	83
2	83
3	83
4	83
5	84
6	84
7	84
8	85
9	86
10	86
11	87
12	87
13	87
14	88
15	88
16	88
17	89
18	89
19	89
20	90
21	90
22	90
23	90
24	91
25	91
26	91
27	91
28	91
29	91
30	91

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

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

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

	Rain chance (%)
1	83
2	83
3	83
4	83
5	84
6	84
7	84
8	85
9	86
10	86
11	87
12	87
13	87
14	88
15	88
16	88
17	89
18	89
19	89
20	90
21	90
22	90
23	90
24	91
25	91
26	91
27	91
28	91
29	91
30	91

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

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

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

	Rain chance (%)
1	83
2	83
3	83
4	83
5	84
6	84
7	84
8	85
9	86
10	86
11	87
12	87
13	87
14	88
15	88
16	88
17	89
18	89
19	89
20	90
21	90
22	90
23	90
24	91
25	91
26	91
27	91
28	91
29	91
30	91

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