Guaratuba weather in September

In September, Guaratuba sees average daytime highs of 22°C and overnight lows near 17°C, with 133 mm of rain across 13.9 wet days and about 11.8 hours of daylight. It is the 9th-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 17% of the time in September, and the air most often feels humid.

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 Guaratuba's 8th-clearest and 4th-windiest month. For the whole year in context, see Guaratuba's year-round climate.

Daytime high
22°
9th warmest
Overnight low
17°
4th coldest
Rainfall
133 mm
13.9 wet days
Daylight
11 h 54 min
7:13 AM – 7:04 PM
Cloud cover
73%
8th clearest
Wind
11 km/h
4th windiest
Solar energy
3.62 kWh/m²
Travel score
5.8
out of 10

Guaratuba is 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 22°C through the month.

A typical September day in Guaratuba reaches about 22°C in the afternoon and slips back to 17°C overnight — a 5°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 25°C. Set against its neighbours, September runs about 1°C warmer than August and about 1°C cooler than October.

10°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12216
22216
32216
42217
52217
62217
72217
82217
92217
102217
112217
122217
132217
142217
152217
162217
172217
182217
192217
202217
212217
222217
232217
242217
252217
262217
272217
282218
292218
302218

Guaratuba weather by month

How September compares with the rest of the year at a glance. September is the 9th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 23°27123.313.44.1
Feb28° / 23°24920.612.94.1
Mar27° / 22°20621.412.24.7
Apr26° / 20°11914.211.46.0
May23° / 18°11512.710.86.4
Jun22° / 16°9810.110.46.5
Jul21° / 15°899.910.56.4
Aug21° / 16°819.411.16.6
Sep22° / 17°13313.911.85.8
Oct23° / 19°13616.412.65.5
Nov25° / 20°15316.613.35.5
Dec27° / 22°18619.213.65.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 17% 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 71%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14357
24159
34060
43862
53664
63565
73466
83169
93169
103070
113070
122872
132872
142872
152773
162773
172773
182872
192773
202773
212674
222674
232674
242575
252575
262575
272377
282377
292377
302278

Chance of precipitation in September

Any precipitation

Guaratuba gets around 133 mm of rain over 13.9 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 45% and peaks near 56% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
135
236
337
438
539
639
740
840
941
1041
1142
1242
1343
1443
1544
1644
1745
1846
1947
2048
2149
2250
2351
2452
2553
2654
2755
2855
2956
3056

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 41% of days. Sticky, muggy-or-worse air turns up on roughly 24% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1152442180
2152442190
3152441200
4152341210
5152341210
6152241220
7152240220
8152240230
9142241230
10142241230
11142241230
12132241230
13132241230
14132241231
15122241231
16122241241
17122241231
18122341231
19122341231
20122341231
21112341231
22112341231
23112341231
24102342242
25102342242
2692242252
2792242252
2892242262
2982241272
3082141282

Wind in September

Winds average 11 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm

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 7:30 AM to 6:57 AM, and sunset from 6:58 PM to 7:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.57:306:58
211.57:296:58
311.57:286:59
411.57:276:59
511.67:267:00
611.67:257:00
711.67:237:00
811.67:227:01
911.77:217:01
1011.77:207:02
1111.77:197:02
1211.77:187:02
1311.87:177:03
1411.87:157:03
1511.87:147:04
1611.97:137:04
1711.97:127:05
1811.97:117:05
1911.97:107:05
2012.07:097:06
2112.07:077:06
2212.07:067:07
2312.07:057:07
2412.17:047:07
2512.17:037:08
2612.17:027:08
2712.17:017:09
2812.26:597:09
2912.26:587:10
3012.26:577:10

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.62 kWh/m².

For context, solar energy here swings from a low near 2.57 kWh/m² to a high of 5.51 kWh/m² in December across the year — September's 3.62 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.6Moderate
23.6Moderate
33.6Moderate
43.6Moderate
53.6Moderate
63.6Moderate
73.6Moderate
83.6Moderate
93.6Moderate
103.6Moderate
113.6Moderate
123.6Moderate
133.6Moderate
143.6Moderate
153.6Moderate
163.6Moderate
173.6Moderate
183.6Moderate
193.6Moderate
203.7Moderate
213.7Moderate
223.7Moderate
233.7Moderate
243.7Moderate
253.7Moderate
263.7Moderate
273.7Moderate
283.7Moderate
293.8Moderate
303.8Moderate
Planning a trip in September

Is September a good time to visit Guaratuba?

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

5.8
Sightseeing
6th-best month of the year
4.0
Beach & pool
11th-best month of the year

September is a reasonable time to visit Guaratuba for sightseeing.

What to pack for Guaratuba in September

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

In September, Guaratuba sees daytime highs around 22°C and nights near 17°C. Pack rain gear. About 14 days see rain.

rain gear

Sea temperature near Guaratuba in September

The nearest coast averages about 20°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 20 km away) is warmest in February at about 27°C and coldest in August near 19°C.

It's comfortable for a long swim from Sep 20 to Jun 28 — about 9.3 months when the water holds above 20°C.

20°25°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swimcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr25Warm
May23Refreshing
Jun21Refreshing
Jul19Cool
Aug19Cool
Sep20Cool
Oct21Refreshing
Nov23Refreshing
Dec25Warm

UV index in Guaratuba in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 8 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Guaratuba peaks around January 19 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 at about 5 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighHighVery highExtremeJan 19UV 14Jul 12UV 5
UV index (midday)Level
Jan14Extreme
Feb13Extreme
Mar11Extreme
Apr8Very high
May6High
Jun5High
Jul5Moderate
Aug6High
Sep8Very high
Oct10Very high
Nov12Extreme
Dec13Extreme

Air quality in Guaratuba 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 Guaratuba is worst in August — around 15 µg/m³ PM2.5 (moderate), about 1.8× the cleanest month (February, 9 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodAug 1115 µg/m³Feb 229 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb9Good
Mar9Good
Apr10Good
May12Good
Jun14Moderate
Jul15Moderate
Aug15Moderate
Sep14Moderate
Oct12Good
Nov9Good
Dec9Good
Location & terrain

Where is Guaratuba?

Guaratuba sits at 25.9°S, 48.6°W, 6 m above sea level, in Brazil. The nearest listed city is Matinhos, 7.0 km away.

Topography around Guaratuba

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

Within 3 km, the terrain around Guaratuba has only modest variations in elevation — a maximum elevation change of 138 m around an average of 6 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 824 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,785 m.

The land around Guaratuba is covered by water (49%) and artificial surfaces (25%) within 3 km, water (50%) and trees (38%) within 16 km, and trees (54%) and water (34%) within 80 km.

3 km
138 m
16 km
824 m
80 km
1,785 m
treesgrasslandcroplandartificial surfacesbare terrainwatermangroves
September weather nearby: Matinhos 7.0 km · Pontal do Paraná 24 km · Itapoá 26 km · Garuva 32 km · São Francisco do Sul 41 km · Paranaguá 41 km · Morretes 52 km · Antonina 52 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 Guaratuba (-25.8828°, -48.5747°, elevation 6 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).