Rio do Sul weather in September

In September, Rio do Sul sees average daytime highs of 22°C and overnight lows near 13°C, with 151 mm of rain across 12.4 wet days and about 11.8 hours of daylight. It is the 8th-warmest and 3rd-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 20% of the time in September, and the air most often feels dry.

Daylight stretches from about 11 h 24 min at the start of September to 12 h 12 min by month's end. Set against the rest of the year, September is Rio do Sul's 8th-clearest and 3rd-windiest month. For the whole year in context, see Rio do Sul's year-round climate.

Daytime high
22°
8th warmest
Overnight low
13°
5th coldest
Rainfall
151 mm
12.4 wet days
Daylight
11 h 48 min
7:18 AM – 7:08 PM
Cloud cover
72%
8th clearest
Wind
7 km/h
3rd windiest
Solar energy
3.79 kWh/m²
Travel score
6.0
out of 10

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 Rio do Sul reaches about 22°C in the afternoon and slips back to 13°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 16°C and 28°C. Set against its neighbours, September runs about 1°C warmer than August and about 2°C cooler than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12212
22212
32212
42212
52212
62212
72212
82212
92212
102212
112212
122212
132212
142213
152213
162213
172213
182213
192213
202213
212213
222213
232213
242213
252213
262213
272213
282213
292213
302213

Rio do Sul weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 19°18420.413.54.7
Feb28° / 19°15418.3134.8
Mar27° / 18°10515.212.25.6
Apr24° / 15°829.411.46.8
May21° / 12°1059.110.76.5
Jun19° / 10°1119.810.36.0
Jul19° / 991010.56.0
Aug20° / 10°949.6116.4
Sep22° / 13°15112.411.86.0
Oct23° / 15°15015.112.75.7
Nov25° / 16°12114.813.35.8
Dec27° / 18°14916.513.75.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 20% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 13% of September, with mostly cloudy or overcast conditions the remaining 67%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14555
24555
34357
44258
54060
63961
73862
83763
93664
103466
113466
123367
133268
143268
153169
163169
173070
183070
193070
202971
212872
222872
232773
242773
252773
262674
272674
282674
292575
302476

Chance of precipitation in September

Any precipitation

Rio do Sul gets around 151 mm of rain over 12.4 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 41% and peaks near 48% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
131
231
332
433
533
634
735
836
937
1037
1138
1239
1340
1441
1541
1642
1743
1843
1944
2045
2145
2246
2346
2447
2547
2647
2747
2847
2948
3048

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 38% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
14239181
24238191
34138201
44137211
54037221
64037221
73937231
83937232
93937232
103837232
113837232
123837242
133836242
143736242
153736242
163736243
173835243
183835243
193835243
203835243
213835243
223735253
233735253
243636253
253536263
263536263
273437263
283337273
293237274
303237284

Wind in September

Winds average 7 km/h in September.

Across September, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
267calm
277calm
287calm
297calm
307calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 24 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 48 minutes over September. Sunrise moves from 7:35 AM to 7:01 AM, and sunset from 7:01 PM to 7:15 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.47:357:01
211.57:347:02
311.57:337:02
411.57:327:03
511.57:317:03
611.67:307:04
711.67:287:04
811.67:277:05
911.67:267:05
1011.77:257:05
1111.77:247:06
1211.77:227:06
1311.87:217:07
1411.87:207:07
1511.87:197:08
1611.87:187:08
1711.97:167:09
1811.97:157:09
1911.97:147:09
2012.07:137:10
2112.07:127:10
2212.07:107:11
2312.07:097:11
2412.17:087:12
2512.17:077:12
2612.17:067:13
2712.17:057:13
2812.27:037:14
2912.27:027:14
3012.27:017:15

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.79 kWh/m².

For context, solar energy here swings from a low near 2.5 kWh/m² to a high of 5.6 kWh/m² in December across the year — September's 3.79 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.8Moderate
23.8Moderate
33.8Moderate
43.8Moderate
53.8Moderate
63.8Moderate
73.8Moderate
83.8Moderate
93.8Moderate
103.8Moderate
113.8Moderate
123.8Moderate
133.8Moderate
143.8Moderate
153.8Moderate
163.8Moderate
173.8Moderate
183.8Moderate
193.8Moderate
203.8Moderate
213.8Moderate
223.8Moderate
233.8Moderate
243.8Moderate
253.8Moderate
263.8Moderate
273.8Moderate
283.8Moderate
293.8Moderate
303.8Moderate
Planning a trip in September

Is September a good time to visit Rio do Sul?

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

6.0
Sightseeing
4th-best month of the year
4.0
Beach & pool
8th-best month of the year

September is a reasonable time to visit Rio do Sul for sightseeing.

What to pack for Rio do Sul in September

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

In September, Rio do Sul sees daytime highs around 22°C and nights near 13°C. Worth packing: rain gear. About 12 days see rain.

rain gear

UV index in Rio do Sul in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Rio do Sul peaks around January 19 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 10 at about 5 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighModerateHighVery highExtremeJan 19UV 14Jul 10UV 5
UV index (midday)Level
Jan14Extreme
Feb14Extreme
Mar11Extreme
Apr8Very high
May6High
Jun5Moderate
Jul5Moderate
Aug6High
Sep8Very high
Oct9Very high
Nov12Extreme
Dec13Extreme

Air quality in Rio do Sul 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 Rio do Sul is worst in September — around 15 µg/m³ PM2.5 (moderate), about 1.6× the cleanest month (December, 10 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 915 µg/m³Dec 1710 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb10Good
Mar10Good
Apr11Good
May13Moderate
Jun13Moderate
Jul14Moderate
Aug15Moderate
Sep15Moderate
Oct12Good
Nov10Good
Dec10Good
Location & terrain

Where is Rio do Sul?

Rio do Sul sits at 27.2°S, 49.6°W, 346 m above sea level, in Brazil. The nearest listed city is Presidente Getúlio, 18 km away.

Topography around Rio do Sul

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

Within 3 km, the terrain around Rio do Sul has significant variations in elevation — a maximum elevation change of 353 m around an average of 424 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 703 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,735 m.

The land around Rio do Sul is covered by trees (51%) and artificial surfaces (35%) within 3 km, trees (65%) and grassland (21%) within 16 km, and trees (80%) within 80 km.

3 km
353 m
16 km
703 m
80 km
1,735 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Presidente Getúlio 18 km · Ibirama 21 km · Ituporanga 23 km · Pouso Redondo 29 km · Taió 37 km · Indaial 54 km · Otacílio Costa 56 km · Timbó 57 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 Rio do Sul (-27.2142°, -49.6431°, elevation 346 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).