Castelo weather in September

In September, Castelo sees average daytime highs of 26°C and overnight lows near 16°C, with 58 mm of rain across 9.3 wet days and about 11.9 hours of daylight. It is the 8th-warmest and 8th-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 34% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 11 h 36 min at the start of September to 12 h 12 min by month's end. Set against the rest of the year, September is Castelo's 4th-clearest and 1st-windiest month. For the whole year in context, see Castelo's year-round climate.

Daytime high
26°
8th warmest
Overnight low
16°
5th coldest
Rainfall
58 mm
9.3 wet days
Daylight
11 h 54 min
6:43 AM – 6:36 PM
Cloud cover
57%
4th clearest
Wind
8 km/h
1st windiest
Solar energy
4.8 kWh/m²
Travel score
6.9
out of 10

Castelo is human settlement in Brazil.

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 26°C through the month.

A typical September day in Castelo reaches about 26°C in the afternoon and slips back to 16°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 20°C and 30°C. Set against its neighbours, September runs about 1°C warmer than August and on par with October.

10°15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12515
22515
32515
42515
52515
62515
72515
82515
92515
102615
112615
122616
132616
142616
152616
162616
172616
182616
192616
202616
212616
222616
232616
242616
252616
262616
272616
282616
292616
302616

Castelo weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 20°14814.113.14.9
Feb29° / 20°10711.912.74.8
Mar28° / 19°15916.612.15.0
Apr27° / 18°8813.411.56.0
May25° / 16°438.6117.1
Jun24° / 14°235.510.87.8
Jul24° / 14°24610.97.8
Aug24° / 14°266.511.37.7
Sep26° / 16°589.311.96.9
Oct26° / 17°11012.312.56.1
Nov26° / 18°19117.1135.2
Dec28° / 19°2241913.24.8

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 51%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16040
26040
36040
46040
56040
66040
75842
85842
95743
105644
115545
125446
135347
145248
155149
165050
175050
184852
194654
204555
214456
224357
234258
244060
253961
263862
273763
283664
293664
303565

Chance of precipitation in September

Any precipitation

Castelo gets around 58 mm of rain over 9.3 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 30% and peaks near 38% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
123
223
324
424
524
624
725
825
926
1026
1127
1227
1328
1429
1529
1630
1731
1832
1932
2033
2134
2235
2336
2436
2537
2637
2737
2838
2938
3038

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 45% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
11755271
21755271
31755271
41754281
51655281
61654291
71652302
81553302
91551322
101451332
111351342
121350353
131249363
141148374
151147384
161047394
171046405
181044415
19943426
20942426
21941437
22940447
23939458
24938458
25936469
269354610
278344710
288334811
298324811
308324912

Wind in September

Winds average 8 km/h in September, the windiest month of the year.

Across September, daily wind ranges from about 7 km/h on the calmest days to 8 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
108calm
118calm
128calm
138calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
287calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 36 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 36 minutes over September. Sunrise moves from 6:57 AM to 6:29 AM, and sunset from 6:32 PM to 6:39 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.66:576:32
211.66:566:32
311.66:556:33
411.66:546:33
511.76:536:33
611.76:526:33
711.76:516:33
811.76:506:34
911.76:496:34
1011.86:486:34
1111.86:476:34
1211.86:466:35
1311.86:456:35
1411.86:456:35
1511.96:446:35
1611.96:436:36
1711.96:426:36
1811.96:416:36
1911.96:406:36
2012.06:396:37
2112.06:386:37
2212.06:376:37
2312.06:366:37
2412.06:356:37
2512.16:346:38
2612.16:336:38
2712.16:326:38
2812.16:316:39
2912.16:306:39
3012.26:296:39

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.8 kWh/m².

For context, solar energy here swings from a low near 3.53 kWh/m² to a high of 5.96 kWh/m² in February across the year — September's 4.8 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.7Bright
24.7Bright
34.7Bright
44.8Bright
54.8Bright
64.8Bright
74.8Bright
84.8Bright
94.8Bright
104.8Bright
114.8Bright
124.8Bright
134.8Bright
144.8Bright
154.8Bright
164.8Bright
174.8Bright
184.8Bright
194.8Bright
204.8Bright
214.8Bright
224.8Bright
234.8Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.8Bright
Planning a trip in September

Hazard calendar for Castelo

In seasonPeak

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

Castelo's rainy season runs October–March, 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 Castelo?

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

6.9
Sightseeing
5th-best month of the year
6.4
Beach & pool
4th-best month of the year

September is a reasonable time to visit Castelo for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Castelo in September

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

In September, Castelo sees daytime highs around 26°C and nights near 16°C. Worth packing: light clothes, rain gear and sun protection. About 9 days see rain.

light clothesrain gearsun protection

Sea temperature near Castelo in September

The nearest coast averages about 22°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 66 km away) is warmest in March at about 25°C and coldest in September near 22°C.

The water stays above 20°C all year — warm enough for a swim any month.

20°22°24°26°JanFebMarAprMayJunJulAugSepOctNovDecrefreshingwarmcomfortable to swim
Sea temperature (°C)Comfort
Jan24Warm
Feb25Warm
Mar25Warm
Apr25Warm
May25Warm
Jun23Refreshing
Jul23Refreshing
Aug23Refreshing
Sep22Refreshing
Oct23Refreshing
Nov24Refreshing
Dec24Warm

UV index in Castelo in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Castelo peaks around February 11 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 20 at about 6 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeFeb 11UV 14Jun 20UV 6
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar13Extreme
Apr10Very high
May7Very high
Jun6High
Jul7High
Aug9Very high
Sep10Very high
Oct12Extreme
Nov13Extreme
Dec14Extreme
Location & terrain

Where is Castelo?

Castelo sits at 20.6°S, 41.2°W, 129 m above sea level, in Brazil. The nearest listed city is Vargem Alta, 20 km away.

Topography around Castelo

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

Within 3 km, the terrain around Castelo has large variations in elevation — a maximum elevation change of 768 m around an average of 224 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,935 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,841 m.

The land around Castelo is covered by trees (56%) and grassland (37%) within 3 km, trees (53%) and grassland (46%) within 16 km, and trees (50%) and grassland (41%) within 80 km.

3 km
768 m
16 km
1,935 m
80 km
2,841 m
treesgrasslandartificial surfaceswaterwetland
September weather nearby: Vargem Alta 20 km · Cachoeiro de Itapemirim 28 km · Muniz Freire 28 km · Alegre 40 km · Iúna 46 km · Ibatiba 53 km · Mimoso do Sul 55 km · Piúma 55 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
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Castelo (-20.6036°, -41.1847°, elevation 129 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).