Castro weather in September

In September, Castro sees average daytime highs of 22°C and overnight lows near 12°C, with 127 mm of rain across 10.4 wet days and about 11.8 hours of daylight. It is the 8th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 22°C through the month. 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 30 min at the start of September to 12 h 12 min by month's end. Set against the rest of the year, September is Castro's 4th-clearest and 1st-windiest month. For the whole year in context, see Castro's year-round climate.

Daytime high: 22°; 8th warmest
Overnight low: 12°; 5th coldest
Rainfall: 127 mm; 10.4 wet days
Daylight: 11 h 54 min; 7:19 AM – 7:10 PM
Cloud cover: 58%; 4th clearest
Wind: 12 km/h; 1st windiest
Solar energy: 4.63 kWh/m²
Travel score: 6.6; out of 10

Castro is human settlement in Brazil.

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

← August Castro 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 22°C through the month.

A typical September day in Castro reaches about 22°C in the afternoon and slips back to 12°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 28°C. Set against its neighbours, September runs about 1°C warmer than August and about 1°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)	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22	22
Avg low (°C)	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	13	13	13	13	13	13	13	13	13

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

Castro weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 7th-wettest month here — the current month is highlighted below.

Month	High / Low (°C)	Rainfall (mm)	Wet days	Daylight (hours)	Travel score
Jan	26° / 17°	235	23.8	13.4	4.5
Feb	26° / 17°	178	21	12.9	4.6
Mar	25° / 17°	132	18	12.2	5.5
Apr	23° / 15°	70	9.6	11.4	6.9
May	20° / 12°	89	8.9	10.8	6.5
Jun	19° / 11°	93	8.4	10.5	6.5
Jul	19° / 10°	79	7	10.6	6.8
Aug	21° / 11°	72	7.3	11.1	7.2
Sep	22° / 12°	127	10.4	11.8	6.6
Oct	23° / 14°	138	15.1	12.6	5.9
Nov	24° / 15°	133	16.1	13.2	5.8
Dec	26° / 17°	173	20.3	13.5	5.1

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 12% of September, with mostly cloudy or overcast conditions the remaining 52%. 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 (%)	62	61	60	59	58	57	56	55	54	52	51	51	50	48	49	48	47	46	45	44	44	42	41	40	39	38	37	37	36	35
Cloudier (%)	38	39	40	41	42	43	44	45	46	48	49	49	50	52	51	52	53	54	55	56	56	58	59	60	61	62	63	63	64	65

	Clearer (%)	Cloudier (%)
1	62	38
2	61	39
3	60	40
4	59	41
5	58	42
6	57	43
7	56	44
8	55	45
9	54	46
10	52	48
11	51	49
12	51	49
13	50	50
14	48	52
15	49	51
16	48	52
17	47	53
18	46	54
19	45	55
20	44	56
21	44	56
22	42	58
23	41	59
24	40	60
25	39	61
26	38	62
27	37	63
28	37	63
29	36	64
30	35	65

Chance of precipitation in September

Any precipitation

Castro gets around 127 mm of rain over 10.4 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 35% and peaks near 44% 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 (%)	26	27	27	27	28	28	29	30	30	31	31	32	33	33	34	35	35	36	37	38	38	39	40	40	41	41	42	43	43	44

	Rain chance (%)
1	26
2	27
3	27
4	27
5	28
6	28
7	29
8	30
9	30
10	31
11	31
12	32
13	33
14	33
15	34
16	35
17	35
18	36
19	37
20	38
21	38
22	39
23	40
24	40
25	41
26	41
27	42
28	43
29	43
30	44

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 54% 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 (%)	69	68	66	64	63	61	60	59	58	56	55	55	54	53	53	52	52	52	52	51	51	50	49	48	47	46	44	43	42	41
Comfortable (%)	28	29	30	32	33	34	35	36	37	38	39	39	39	40	40	40	40	39	39	39	38	38	38	37	37	37	36	36	36	35
Humid (%)	3	3	4	4	4	5	5	5	5	6	6	6	7	7	7	8	8	9	9	10	11	12	13	14	16	17	19	20	22	23

	Dry (%)	Comfortable (%)	Humid (%)
1	69	28	3
2	68	29	3
3	66	30	4
4	64	32	4
5	63	33	4
6	61	34	5
7	60	35	5
8	59	36	5
9	58	37	5
10	56	38	6
11	55	39	6
12	55	39	6
13	54	39	7
14	53	40	7
15	53	40	7
16	52	40	8
17	52	40	8
18	52	39	9
19	52	39	9
20	51	39	10
21	51	38	11
22	50	38	12
23	49	38	13
24	48	37	14
25	47	37	16
26	46	37	17
27	44	36	19
28	43	36	20
29	42	36	22
30	41	35	23

Wind in September

Winds average 12 km/h in September, the windiest month of the year.

Across September, daily wind ranges from about 11 km/h on the calmest days to 12 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	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12	12
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	light breeze	light breeze	light breeze	light breeze	light breeze

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

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 30 min at the start of September to 12 h 12 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 42 minutes over September. Sunrise moves from 7:35 AM to 7:03 AM, and sunset from 7:05 PM to 7:15 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)	11.5	11.5	11.5	11.6	11.6	11.6	11.6	11.7	11.7	11.7	11.7	11.8	11.8	11.8	11.8	11.9	11.9	11.9	11.9	12.0	12.0	12.0	12.0	12.1	12.1	12.1	12.1	12.2	12.2	12.2
Sunrise (AM)	7:35	7:34	7:33	7:32	7:31	7:30	7:29	7:28	7:26	7:25	7:24	7:23	7:22	7:21	7:20	7:19	7:18	7:16	7:15	7:14	7:13	7:12	7:11	7:10	7:09	7:08	7:06	7:05	7:04	7:03
Sunset (PM)	7:05	7:05	7:05	7:06	7:06	7:06	7:07	7:07	7:08	7:08	7:08	7:09	7:09	7:09	7:10	7:10	7:10	7:11	7:11	7:12	7:12	7:12	7:13	7:13	7:13	7:14	7:14	7:15	7:15	7:15

	Daylight (h)	Sunrise (AM)	Sunset (PM)
1	11.5	7:35	7:05
2	11.5	7:34	7:05
3	11.5	7:33	7:05
4	11.6	7:32	7:06
5	11.6	7:31	7:06
6	11.6	7:30	7:06
7	11.6	7:29	7:07
8	11.7	7:28	7:07
9	11.7	7:26	7:08
10	11.7	7:25	7:08
11	11.7	7:24	7:08
12	11.8	7:23	7:09
13	11.8	7:22	7:09
14	11.8	7:21	7:09
15	11.8	7:20	7:10
16	11.9	7:19	7:10
17	11.9	7:18	7:10
18	11.9	7:16	7:11
19	11.9	7:15	7:11
20	12.0	7:14	7:12
21	12.0	7:13	7:12
22	12.0	7:12	7:12
23	12.0	7:11	7:13
24	12.1	7:10	7:13
25	12.1	7:09	7:13
26	12.1	7:08	7:14
27	12.1	7:06	7:14
28	12.2	7:05	7:15
29	12.2	7:04	7:15
30	12.2	7:03	7:15

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.63 kWh/m².

For context, solar energy here swings from a low near 3.05 kWh/m² to a high of 5.87 kWh/m² in December across the year — September's 4.63 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)	4.6	4.6	4.6	4.6	4.6	4.6	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	4.7	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	4.6	Bright
2	4.6	Bright
3	4.6	Bright
4	4.6	Bright
5	4.6	Bright
6	4.6	Bright
7	4.7	Bright
8	4.7	Bright
9	4.7	Bright
10	4.7	Bright
11	4.7	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	4.7	Bright
22	4.7	Bright
23	4.7	Bright
24	4.7	Bright
25	4.7	Bright
26	4.7	Bright
27	4.7	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 Castro?

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

6.6

Sightseeing

4th-best month of the year

4.8

Beach & pool

5th-best month of the year

September is a reasonable time to visit Castro for sightseeing.

What to pack for Castro in September

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

In September, Castro sees daytime highs around 22°C and nights near 12°C. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

UV index in Castro 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 Castro peaks around January 19 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 13 at about 5 (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)	15	15	12	9	7	6	5	7	5	11	14	14
Level	Extreme	Extreme	Extreme	Very high	High	High	High	High	High	Extreme	Extreme	Extreme

	UV index (midday)	Level
Jan	15	Extreme
Feb	15	Extreme
Mar	12	Extreme
Apr	9	Very high
May	7	High
Jun	6	High
Jul	5	High
Aug	7	High
Sep	5	High
Oct	11	Extreme
Nov	14	Extreme
Dec	14	Extreme

Air quality in Castro 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 Castro is worst in September — around 17 µg/m³ PM2.5 (moderate), about 2.6× the cleanest month (March, 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	7	6	7	8	8	10	14	17	10	7	7
Level	Good	Good	Good	Good	Good	Good	Good	Moderate	Moderate	Good	Good	Good

	PM2.5 (µg/m³)	Level
Jan	7	Good
Feb	7	Good
Mar	6	Good
Apr	7	Good
May	8	Good
Jun	8	Good
Jul	10	Good
Aug	14	Moderate
Sep	17	Moderate
Oct	10	Good
Nov	7	Good
Dec	7	Good

Location & terrain

Where is Castro?

Castro sits at 24.8°S, 50.0°W, 986 m above sea level, in Brazil. The nearest listed city is Piraí do Sul, 30 km away.

Topography around Castro

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

Within 3 km, the terrain around Castro has only modest variations in elevation — a maximum elevation change of 151 m around an average of 1,004 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 304 m; within 80 km, large variations in elevation — a maximum elevation change of 1,128 m.

The land around Castro is covered by trees (42%), artificial surfaces (28%) and grassland (20%) within 3 km, trees (42%) and cropland (42%) within 16 km, and trees (58%) and cropland (30%) within 80 km.

3 km

151 m

trees 42%

16 km

304 m

trees 42%

80 km

1,128 m

trees 58%

treesgrasslandcroplandartificial surfaceswater

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

September weather nearby: Piraí do Sul 30 km · Ponta Grossa 37 km · Tibagi 51 km · Jaguariaíva 68 km · Palmeira 71 km · Arapoti 73 km · Cerro Azul 76 km · Imbituva 77 km

Brazil travel facts

Travel advisory: Level 2; Exercise Increased Caution
Power plugs: Type C / N; 127 / 220 V · 60 Hz
Prices: ≈ 46% of US; price level, 2025
GDP per capita: $10,713; 2025
Happiness: 6.6 / 10; World Happiness, 2025
Safe drinking water: 89%; of population, 2024
Homicide rate: 19.3; per 100k, 2023
Road deaths: 16; per 100k/yr, 2019
Income group: Upper middle; World Bank
English: Low; EF EPI 482
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 Castro (-24.7893°, -50.0123°, elevation 986 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. 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	22	12
2	22	12
3	22	12
4	22	12
5	22	12
6	22	12
7	22	12
8	22	12
9	22	12
10	22	12
11	22	12
12	22	12
13	22	12
14	22	12
15	22	12
16	22	12
17	22	12
18	22	12
19	22	12
20	22	12
21	22	12
22	22	13
23	22	13
24	22	13
25	22	13
26	22	13
27	22	13
28	22	13
29	22	13
30	22	13

	Clearer (%)	Cloudier (%)
1	62	38
2	61	39
3	60	40
4	59	41
5	58	42
6	57	43
7	56	44
8	55	45
9	54	46
10	52	48
11	51	49
12	51	49
13	50	50
14	48	52
15	49	51
16	48	52
17	47	53
18	46	54
19	45	55
20	44	56
21	44	56
22	42	58
23	41	59
24	40	60
25	39	61
26	38	62
27	37	63
28	37	63
29	36	64
30	35	65

	Rain chance (%)
1	26
2	27
3	27
4	27
5	28
6	28
7	29
8	30
9	30
10	31
11	31
12	32
13	33
14	33
15	34
16	35
17	35
18	36
19	37
20	38
21	38
22	39
23	40
24	40
25	41
26	41
27	42
28	43
29	43
30	44

	Dry (%)	Comfortable (%)	Humid (%)
1	69	28	3
2	68	29	3
3	66	30	4
4	64	32	4
5	63	33	4
6	61	34	5
7	60	35	5
8	59	36	5
9	58	37	5
10	56	38	6
11	55	39	6
12	55	39	6
13	54	39	7
14	53	40	7
15	53	40	7
16	52	40	8
17	52	40	8
18	52	39	9
19	52	39	9
20	51	39	10
21	51	38	11
22	50	38	12
23	49	38	13
24	48	37	14
25	47	37	16
26	46	37	17
27	44	36	19
28	43	36	20
29	42	36	22
30	41	35	23

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

	Clearer (%)	Cloudier (%)
1	62	38
2	61	39
3	60	40
4	59	41
5	58	42
6	57	43
7	56	44
8	55	45
9	54	46
10	52	48
11	51	49
12	51	49
13	50	50
14	48	52
15	49	51
16	48	52
17	47	53
18	46	54
19	45	55
20	44	56
21	44	56
22	42	58
23	41	59
24	40	60
25	39	61
26	38	62
27	37	63
28	37	63
29	36	64
30	35	65

	Rain chance (%)
1	26
2	27
3	27
4	27
5	28
6	28
7	29
8	30
9	30
10	31
11	31
12	32
13	33
14	33
15	34
16	35
17	35
18	36
19	37
20	38
21	38
22	39
23	40
24	40
25	41
26	41
27	42
28	43
29	43
30	44

	Dry (%)	Comfortable (%)	Humid (%)
1	69	28	3
2	68	29	3
3	66	30	4
4	64	32	4
5	63	33	4
6	61	34	5
7	60	35	5
8	59	36	5
9	58	37	5
10	56	38	6
11	55	39	6
12	55	39	6
13	54	39	7
14	53	40	7
15	53	40	7
16	52	40	8
17	52	40	8
18	52	39	9
19	52	39	9
20	51	39	10
21	51	38	11
22	50	38	12
23	49	38	13
24	48	37	14
25	47	37	16
26	46	37	17
27	44	36	19
28	43	36	20
29	42	36	22
30	41	35	23

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

	Clearer (%)	Cloudier (%)
1	62	38
2	61	39
3	60	40
4	59	41
5	58	42
6	57	43
7	56	44
8	55	45
9	54	46
10	52	48
11	51	49
12	51	49
13	50	50
14	48	52
15	49	51
16	48	52
17	47	53
18	46	54
19	45	55
20	44	56
21	44	56
22	42	58
23	41	59
24	40	60
25	39	61
26	38	62
27	37	63
28	37	63
29	36	64
30	35	65

	Rain chance (%)
1	26
2	27
3	27
4	27
5	28
6	28
7	29
8	30
9	30
10	31
11	31
12	32
13	33
14	33
15	34
16	35
17	35
18	36
19	37
20	38
21	38
22	39
23	40
24	40
25	41
26	41
27	42
28	43
29	43
30	44

	Dry (%)	Comfortable (%)	Humid (%)
1	69	28	3
2	68	29	3
3	66	30	4
4	64	32	4
5	63	33	4
6	61	34	5
7	60	35	5
8	59	36	5
9	58	37	5
10	56	38	6
11	55	39	6
12	55	39	6
13	54	39	7
14	53	40	7
15	53	40	7
16	52	40	8
17	52	40	8
18	52	39	9
19	52	39	9
20	51	39	10
21	51	38	11
22	50	38	12
23	49	38	13
24	48	37	14
25	47	37	16
26	46	37	17
27	44	36	19
28	43	36	20
29	42	36	22
30	41	35	23