Foz do Iguacu weather in September

In September, Foz do Iguacu sees average daytime highs of 27°C and overnight lows near 16°C, with 154 mm of rain across 9.9 wet days and about 11.8 hours of daylight. It is the 8th-warmest and 6th-wettest month of the year here.

Day-to-day highs hold fairly steady near 27°C through the month. The sky is clear or mostly clear about 47% 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 Foz do Iguacu's 3rd-clearest and 2nd-windiest month. For the whole year in context, see Foz do Iguacu's year-round climate.

Daytime high
27°
8th warmest
Overnight low
16°
5th coldest
Rainfall
154 mm
9.9 wet days
Daylight
11 h 54 min
7:37 AM – 7:28 PM
Cloud cover
48%
3rd clearest
Wind
10 km/h
2nd windiest
Solar energy
4.78 kWh/m²
Travel score
6.7
out of 10

Foz do Iguacu 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 27°C through the month.

A typical September day in Foz do Iguacu reaches about 27°C in the afternoon and slips back to 16°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 20°C and 33°C. Set against its neighbours, September runs about 2°C warmer than August and about 2°C cooler than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12615
22615
32616
42616
52716
62716
72716
82716
92716
102716
112716
122716
132716
142716
152716
162716
172716
182716
192716
202716
212716
222717
232717
242717
252717
262717
272717
282717
292717
302717

How September really feels in Foz do Iguacu

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Foz do Iguacu weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 22°15715.413.43.9
Feb31° / 22°15213.912.94.1
Mar30° / 21°14112.512.24.8
Apr28° / 18°1389.211.46.3
May24° / 15°1629.210.87.1
Jun22° / 14°1379.210.46.9
Jul22° / 13°1178.510.67.2
Aug25° / 14°946.911.17.6
Sep27° / 16°1549.911.86.7
Oct28° / 19°19813.212.65.4
Nov30° / 20°15811.513.25.0
Dec31° / 21°18414.913.64.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 47% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 11% of September, with mostly cloudy or overcast conditions the remaining 42%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16733
26634
36535
46535
56337
66337
76238
86238
96139
106139
116139
126040
136040
145941
155941
165842
175941
185842
195743
205644
215644
225545
235446
245248
255248
265149
275050
284951
294852
304753

Chance of precipitation in September

Any precipitation

Foz do Iguacu gets around 154 mm of rain over 9.9 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 33% and peaks near 41% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
124
225
325
425
526
627
727
828
929
1029
1130
1230
1331
1432
1532
1633
1734
1834
1935
2036
2136
2237
2338
2439
2539
2640
2740
2841
2941
3041

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 33% of days. Sticky, muggy-or-worse air turns up on roughly 16% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
130343060
230333070
329333070
429333180
528323180
628323190
7273132100
8273132100
9273033110
10272933110
11262833120
12262834120
13262734130
14262635140
15252535140
16252435150
17252435160
18252335170
19252235170
20252235180
21242234190
22232134211
23232134221
24222134231
25212133241
26202133261
27192033271
28182033281
29172033291
30162033301

Wind in September

Winds average 10 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
611calm
711calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm

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 7:54 AM to 7:21 AM, and sunset from 7:22 PM to 7:34 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.57:547:22
211.57:537:23
311.57:527:23
411.57:517:23
511.67:507:24
611.67:487:24
711.67:477:25
811.67:467:25
911.77:457:25
1011.77:447:26
1111.77:437:26
1211.87:427:27
1311.87:417:27
1411.87:397:27
1511.87:387:28
1611.97:377:28
1711.97:367:29
1811.97:357:29
1911.97:347:29
2012.07:337:30
2112.07:317:30
2212.07:307:31
2312.07:297:31
2412.17:287:31
2512.17:277:32
2612.17:267:32
2712.17:257:33
2812.27:247:33
2912.27:227:34
3012.27:217:34

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.78 kWh/m².

For context, solar energy here swings from a low near 2.83 kWh/m² to a high of 6.38 kWh/m² in December across the year — September's 4.78 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.7Bright
54.7Bright
64.7Bright
74.7Bright
84.7Bright
94.7Bright
104.7Bright
114.7Bright
124.8Bright
134.8Bright
144.8Bright
154.8Bright
164.8Bright
174.8Bright
184.8Bright
194.8Bright
204.8Bright
214.9Bright
224.9Bright
234.9Bright
244.9Bright
254.9Bright
264.9Bright
274.9Bright
284.9Bright
294.9Bright
304.9Bright
Planning a trip in September

Is September a good time to visit Foz do Iguacu?

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

6.7
Sightseeing
5th-best month of the year
6.7
Beach & pool
3rd-best month of the year

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

What to pack for Foz do Iguacu in September

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

In September, Foz do Iguacu sees daytime highs around 27°C and nights near 16°C. Worth packing: light clothes, rain gear and sun protection. About 10 days see rain.

light clothesrain gearsun protection

UV index in Foz do Iguacu in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Foz do Iguacu peaks around January 19 at about 15 (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 15Jul 12UV 5
UV index (midday)Level
Jan15Extreme
Feb14Extreme
Mar11Extreme
Apr9Very high
May6High
Jun5High
Jul5Moderate
Aug6High
Sep6High
Oct10Very high
Nov12Extreme
Dec13Extreme

Air quality in Foz do Iguacu 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 Foz do Iguacu is worst in September — around 23 µg/m³ PM2.5 (moderate), about 2.9× the cleanest month (March, 8 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 1622 µg/m³Mar 108 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb8Good
Mar8Good
Apr9Good
May10Good
Jun10Good
Jul11Good
Aug14Moderate
Sep23Moderate
Oct14Moderate
Nov10Good
Dec8Good
Location & terrain

Where is Foz do Iguacu?

Foz do Iguacu sits at 25.5°S, 54.6°W, 179 m above sea level, in Brazil. The nearest listed city is Presidente Franco, 3.0 km away.

Topography around Foz do Iguacu

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

Within 3 km, the terrain around Foz do Iguacu has only modest variations in elevation — a maximum elevation change of 128 m around an average of 176 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 200 m; within 80 km, significant variations in elevation — a maximum elevation change of 568 m.

The land around Foz do Iguacu is covered by artificial surfaces (48%) and trees (37%) within 3 km, trees (40%) and cropland (24%) within 16 km, and trees (44%) and cropland (39%) within 80 km.

3 km
128 m
16 km
200 m
80 km
568 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Presidente Franco 3.0 km · Iguazu 6.0 km · Ciudad del Este 8.0 km · Santa Terezinha de Itaipu 22 km · São Miguel do Iguaçu 42 km · Colonia Wanda 47 km · Puerto Esperanza 53 km · Medianeira 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 Foz do Iguacu (-25.5478°, -54.5881°, elevation 179 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).