Arauco weather in September

In September, Arauco sees average daytime highs of 15°C and overnight lows near 6°C, with 88 mm of rain across 8.1 wet days and about 11.7 hours of daylight. It is the 8th-warmest and 5th-wettest month of the year here.

Highs climb over the month, from about 14°C in the first days to 16°C by the end. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels dry.

Daylight stretches from about 11 h 12 min at the start of September to 12 h 18 min by month's end. Set against the rest of the year, September is Arauco's 8th-clearest and 7th-windiest month. For the whole year in context, see Arauco's year-round climate.

Daytime high: 15°; 8th warmest
Overnight low: 6°; 4th coldest
Rainfall: 88 mm; 8.1 wet days
Daylight: 11 h 48 min; 7:55 AM – 7:41 PM
Cloud cover: 54%; 8th clearest
Wind: 11 km/h; 7th windiest
Solar energy: 4.52 kWh/m²
Travel score: 4.7; out of 10

Arauco is city in Chile.

Density: 3,997/km²; people per km²
Founded: 1552

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

← August Arauco 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

Highs climb over the month, from about 14°C in the first days to 16°C by the end.

A typical September day in Arauco reaches about 15°C in the afternoon and slips back to 6°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 12°C and 18°C. Set against its neighbours, September runs about 2°C warmer than August and about 2°C cooler than 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)	14	14	14	14	14	14	14	14	14	14	14	15	15	15	15	15	15	15	15	15	15	15	15	15	16	16	16	16	16	16
Avg low (°C)	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	6	7	7

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

Arauco weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 5th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	23° / 12°	10	1.7	14.3	9.0
Feb	23° / 12°	15	2.2	13.4	8.9
Mar	21° / 10°	25	3.5	12.3	8.1
Apr	18° / 8°	72	6.2	11.1	6.4
May	15° / 7°	178	10.9	10	4.2
Jun	12° / 6°	250	14.8	9.5	2.9
Jul	12° / 5°	196	13.6	9.7	2.9
Aug	13° / 5°	167	12.4	10.6	3.4
Sep	15° / 6°	88	8.1	11.7	4.7
Oct	17° / 7°	61	7.4	13	5.8
Nov	19° / 9°	32	4.3	14	7.3
Dec	22° / 11°	25	3.5	14.5	8.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 14% of September, with mostly cloudy or overcast conditions the remaining 50%.

	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 (%)	43	44	46	47	49	49	50	50	51	51	50	51	51	52	52	52	52	52	52	52	52	52	52	51	51	52	52	52	52	53
Cloudier (%)	57	56	54	53	51	51	50	50	49	49	50	49	49	48	48	48	48	48	48	48	48	48	48	49	49	48	48	48	48	47

	Clearer (%)	Cloudier (%)
1	43	57
2	44	56
3	46	54
4	47	53
5	49	51
6	49	51
7	50	50
8	50	50
9	51	49
10	51	49
11	50	50
12	51	49
13	51	49
14	52	48
15	52	48
16	52	48
17	52	48
18	52	48
19	52	48
20	52	48
21	52	48
22	52	48
23	52	48
24	51	49
25	51	49
26	52	48
27	52	48
28	52	48
29	52	48
30	53	47

Chance of precipitation in September

Any precipitation

Arauco gets around 88 mm of rain over 8.1 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 28% and peaks near 36% on the wettest days. The odds ease 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 (%)	36	35	35	34	33	32	31	31	30	30	30	29	29	28	27	27	26	25	25	25	24	24	24	24	24	24	24	24	24	24

	Rain chance (%)
1	36
2	35
3	35
4	34
5	33
6	32
7	31
8	31
9	30
10	30
11	30
12	29
13	29
14	28
15	27
16	27
17	26
18	25
19	25
20	25
21	24
22	24
23	24
24	24
25	24
26	24
27	24
28	24
29	24
30	24

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the dry band about 100% of days. It rarely turns muggy — the humid and sticky bands barely register.

	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
Dry (%)	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100	100

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

Wind in September

Winds average 11 km/h in September.

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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 12 min at the start of September to 12 h 18 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 66 minutes over September. Sunrise moves from 8:18 AM to 7:32 AM, and sunset from 7:28 PM to 7:53 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)	11.2	11.2	11.2	11.3	11.3	11.4	11.4	11.4	11.5	11.5	11.6	11.6	11.6	11.7	11.7	11.8	11.8	11.8	11.9	11.9	12.0	12.0	12.1	12.1	12.1	12.2	12.2	12.3	12.3	12.3
Sunrise (AM)	8:18	8:17	8:15	8:14	8:12	8:10	8:09	8:07	8:06	8:04	8:03	8:01	7:59	7:58	7:56	7:55	7:53	7:51	7:50	7:48	7:47	7:45	7:43	7:42	7:40	7:39	7:37	7:36	7:34	7:32
Sunset (PM)	7:28	7:29	7:30	7:30	7:31	7:32	7:33	7:34	7:35	7:35	7:36	7:37	7:38	7:39	7:40	7:41	7:41	7:42	7:43	7:44	7:45	7:46	7:47	7:47	7:48	7:49	7:50	7:51	7:52	7:53

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	11.2	8:18	7:28
2	11.2	8:17	7:29
3	11.2	8:15	7:30
4	11.3	8:14	7:30
5	11.3	8:12	7:31
6	11.4	8:10	7:32
7	11.4	8:09	7:33
8	11.4	8:07	7:34
9	11.5	8:06	7:35
10	11.5	8:04	7:35
11	11.6	8:03	7:36
12	11.6	8:01	7:37
13	11.6	7:59	7:38
14	11.7	7:58	7:39
15	11.7	7:56	7:40
16	11.8	7:55	7:41
17	11.8	7:53	7:41
18	11.8	7:51	7:42
19	11.9	7:50	7:43
20	11.9	7:48	7:44
21	12.0	7:47	7:45
22	12.0	7:45	7:46
23	12.1	7:43	7:47
24	12.1	7:42	7:47
25	12.1	7:40	7:48
26	12.2	7:39	7:49
27	12.2	7:37	7:50
28	12.3	7:36	7:51
29	12.3	7:34	7:52
30	12.3	7:32	7:53

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.52 kWh/m².

For context, solar energy here swings from a low near 1.78 kWh/m² to a high of 8.52 kWh/m² in January across the year — September's 4.52 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)	3.6	3.7	3.8	3.8	3.9	4.0	4.0	4.1	4.1	4.2	4.3	4.3	4.4	4.4	4.5	4.6	4.6	4.7	4.7	4.8	4.8	4.9	4.9	5.0	5.0	5.1	5.1	5.2	5.2	5.3
Level	Moderate	Moderate	Moderate	Moderate	Moderate	Moderate	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	3.6	Moderate
2	3.7	Moderate
3	3.8	Moderate
4	3.8	Moderate
5	3.9	Moderate
6	4.0	Moderate
7	4.0	Bright
8	4.1	Bright
9	4.1	Bright
10	4.2	Bright
11	4.3	Bright
12	4.3	Bright
13	4.4	Bright
14	4.4	Bright
15	4.5	Bright
16	4.6	Bright
17	4.6	Bright
18	4.7	Bright
19	4.7	Bright
20	4.8	Bright
21	4.8	Bright
22	4.9	Bright
23	4.9	Bright
24	5.0	Bright
25	5.0	Bright
26	5.1	Bright
27	5.1	Bright
28	5.2	Bright
29	5.2	Bright
30	5.3	Bright

Planning a trip in September

Hazard calendar for Arauco

In seasonPeak

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

Arauco's rainy season runs May–August, 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 Arauco?

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

4.7

Sightseeing

8th-best month of the year

0.1

Beach & pool

9th-best month of the year

September is a reasonable time to visit Arauco for sightseeing.

What to pack for Arauco in September

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

In September, Arauco sees daytime highs around 15°C and nights near 6°C. Worth packing: a warm layer, rain gear and sun protection. About 8 days see rain.

a warm layerrain gearsun protection

Sea temperature near Arauco in September

The nearest coast averages about 12°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 14 km away) is warmest in January at about 15°C and coldest in August near 12°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Sea temperature (°C)	15	15	14	14	13	12	12	12	12	12	13	14
Comfort	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing	Bracing

	Sea temperature (°C)	Comfort
Jan	15	Bracing
Feb	15	Bracing
Mar	14	Bracing
Apr	14	Bracing
May	13	Bracing
Jun	12	Bracing
Jul	12	Bracing
Aug	12	Bracing
Sep	12	Bracing
Oct	12	Bracing
Nov	13	Bracing
Dec	14	Bracing

UV index in Arauco in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Arauco peaks around January 12 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 16 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
UV index (midday)	12	11	9	5	3	2	3	3	5	8	10	12
Level	Extreme	Extreme	Very high	Moderate	Moderate	Low	Moderate	Moderate	Moderate	Very high	Very high	Extreme

	UV index (midday)	Level
Jan	12	Extreme
Feb	11	Extreme
Mar	9	Very high
Apr	5	Moderate
May	3	Moderate
Jun	2	Low
Jul	3	Moderate
Aug	3	Moderate
Sep	5	Moderate
Oct	8	Very high
Nov	10	Very high
Dec	12	Extreme

Location & terrain

Where is Arauco?

Arauco sits at 37.2°S, 73.3°W, 13 m above sea level, in Chile. The nearest listed city is Lota, 22 km away.

Topography around Arauco

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

Within 3 km, the terrain around Arauco has only modest variations in elevation — a maximum elevation change of 107 m around an average of 20 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 656 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,511 m.

The land around Arauco is covered by trees (35%), water (31%) and grassland (20%) within 3 km, trees (45%) and water (37%) within 16 km, and trees (49%) and water (38%) within 80 km.

3 km

107 m

trees 35%

16 km

656 m

trees 45%

80 km

1,511 m

trees 49%

treesgrasslandcroplandartificial surfacesbare terrainwaterwetland

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

September weather nearby: Lota 22 km · Curanilahue 26 km · Coronel 28 km · Chiguayante 44 km · Los Álamos 44 km · Hualqui 46 km · San Pedro de la Paz 49 km · Lebu 50 km

Chile travel facts

Travel advisory: Level 2; Exercise Increased Caution
Power plugs: Type C / F / L; 220 V · 50 Hz
Prices: ≈ 48% of US; price level, 2025
GDP per capita: $17,995; 2025
Happiness: 6.3 / 10; World Happiness, 2025
Safe drinking water: 98%; of population, 2024
Homicide rate: 6.3; per 100k, 2023
Road deaths: 14.9; per 100k/yr, 2019
Income group: High; World Bank
English: Moderate; EF EPI 517
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 Arauco (-37.2463°, -73.3175°, elevation 13 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	14	6
2	14	6
3	14	6
4	14	6
5	14	6
6	14	6
7	14	6
8	14	6
9	14	6
10	14	6
11	14	6
12	15	6
13	15	6
14	15	6
15	15	6
16	15	6
17	15	6
18	15	6
19	15	6
20	15	6
21	15	6
22	15	6
23	15	6
24	15	6
25	16	6
26	16	6
27	16	6
28	16	6
29	16	7
30	16	7

	Clearer (%)	Cloudier (%)
1	43	57
2	44	56
3	46	54
4	47	53
5	49	51
6	49	51
7	50	50
8	50	50
9	51	49
10	51	49
11	50	50
12	51	49
13	51	49
14	52	48
15	52	48
16	52	48
17	52	48
18	52	48
19	52	48
20	52	48
21	52	48
22	52	48
23	52	48
24	51	49
25	51	49
26	52	48
27	52	48
28	52	48
29	52	48
30	53	47

	Rain chance (%)
1	36
2	35
3	35
4	34
5	33
6	32
7	31
8	31
9	30
10	30
11	30
12	29
13	29
14	28
15	27
16	27
17	26
18	25
19	25
20	25
21	24
22	24
23	24
24	24
25	24
26	24
27	24
28	24
29	24
30	24

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

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

	Clearer (%)	Cloudier (%)
1	43	57
2	44	56
3	46	54
4	47	53
5	49	51
6	49	51
7	50	50
8	50	50
9	51	49
10	51	49
11	50	50
12	51	49
13	51	49
14	52	48
15	52	48
16	52	48
17	52	48
18	52	48
19	52	48
20	52	48
21	52	48
22	52	48
23	52	48
24	51	49
25	51	49
26	52	48
27	52	48
28	52	48
29	52	48
30	53	47

	Rain chance (%)
1	36
2	35
3	35
4	34
5	33
6	32
7	31
8	31
9	30
10	30
11	30
12	29
13	29
14	28
15	27
16	27
17	26
18	25
19	25
20	25
21	24
22	24
23	24
24	24
25	24
26	24
27	24
28	24
29	24
30	24

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100

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

	Clearer (%)	Cloudier (%)
1	43	57
2	44	56
3	46	54
4	47	53
5	49	51
6	49	51
7	50	50
8	50	50
9	51	49
10	51	49
11	50	50
12	51	49
13	51	49
14	52	48
15	52	48
16	52	48
17	52	48
18	52	48
19	52	48
20	52	48
21	52	48
22	52	48
23	52	48
24	51	49
25	51	49
26	52	48
27	52	48
28	52	48
29	52	48
30	53	47

	Rain chance (%)
1	36
2	35
3	35
4	34
5	33
6	32
7	31
8	31
9	30
10	30
11	30
12	29
13	29
14	28
15	27
16	27
17	26
18	25
19	25
20	25
21	24
22	24
23	24
24	24
25	24
26	24
27	24
28	24
29	24
30	24

	Dry (%)
1	100
2	100
3	100
4	100
5	100
6	100
7	100
8	100
9	100
10	100
11	100
12	100
13	100
14	100
15	100
16	100
17	100
18	100
19	100
20	100
21	100
22	100
23	100
24	100
25	100
26	100
27	100
28	100
29	100
30	100