Iguazu weather in September

In September, Iguazu sees average daytime highs of 27°C and overnight lows near 16°C, with 155 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 46% 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 Iguazu's 3rd-clearest and 2nd-windiest month. For the whole year in context, see Iguazu's year-round climate.

Daytime high
27°
8th warmest
Overnight low
16°
5th coldest
Rainfall
155 mm
9.9 wet days
Daylight
11 h 54 min
6:37 AM – 6:28 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

Iguazu is human settlement.

Founded
1902

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 Iguazu 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
32615
42616
52616
62616
72616
82716
92716
102716
112716
122716
132716
142716
152716
162716
172716
182716
192716
202716
212716
222716
232717
242717
252717
262717
272717
282717
292717
302717

How September really feels in Iguazu

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.

Iguazu 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°15715.313.43.9
Feb31° / 22°1511412.94.1
Mar30° / 21°14112.512.24.8
Apr28° / 18°1389.411.46.3
May24° / 15°1629.110.87.1
Jun22° / 14°1379.210.46.9
Jul22° / 13°1188.510.67.2
Aug25° / 14°94711.17.7
Sep27° / 16°1559.911.86.7
Oct28° / 19°19713.212.65.5
Nov30° / 20°15811.713.35.0
Dec31° / 21°18414.813.64.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 46% 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 41%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16832
26832
36733
46733
56634
66535
76535
86436
96436
106337
116238
126238
136238
146139
156139
166040
176040
185941
195842
205743
215644
225545
235446
245446
255347
265248
275050
285050
294951
304852

Chance of precipitation in September

Any precipitation

Iguazu gets around 155 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 42% 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
426
526
627
727
828
928
1029
1130
1230
1331
1432
1532
1633
1734
1834
1935
2036
2137
2238
2338
2439
2540
2640
2741
2841
2941
3042

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 34% of days. Sticky, muggy-or-worse air turns up on roughly 17% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
130333060
230333170
329323170
429323180
528313290
628313290
7283032100
8273032100
9272933110
10272833110
11272834120
12262734130
13262634130
14262535140
15262535150
16252435150
17252335160
18252335170
19252235180
20242235190
21242135200
22232135211
23222035221
24212035231
25202035241
26191935261
27191935271
28181935281
29171834291
30161834301

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 10 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
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 6:54 AM to 6:21 AM, and sunset from 6:22 PM to 6:34 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.56:546:22
211.56:536:23
311.56:526:23
411.56:516:23
511.66:496:24
611.66:486:24
711.66:476:25
811.66:466:25
911.76:456:25
1011.76:446:26
1111.76:436:26
1211.76:426:27
1311.86:406:27
1411.86:396:27
1511.86:386:28
1611.96:376:28
1711.96:366:29
1811.96:356:29
1911.96:346:29
2012.06:326:30
2112.06:316:30
2212.06:306:31
2312.06:296:31
2412.16:286:31
2512.16:276:32
2612.16:266:32
2712.16:256:33
2812.26:236:33
2912.26:226:34
3012.26:216:34

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 Iguazu?

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 Iguazu for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Iguazu in September

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

In September, Iguazu 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 Iguazu 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 Iguazu 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 Iguazu 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 Iguazu 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 Iguazu?

Iguazu sits at 25.6°S, 54.6°W, 177 m above sea level, in Argentina. The nearest listed city is Presidente Franco, 5.0 km away.

Topography around Iguazu

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

Within 3 km, the terrain around Iguazu has only modest variations in elevation — a maximum elevation change of 139 m around an average of 175 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 198 m; within 80 km, significant variations in elevation — a maximum elevation change of 568 m.

The land around Iguazu is covered by trees (50%) and artificial surfaces (30%) within 3 km, trees (52%) and cropland (22%) within 16 km, and trees (46%) and cropland (38%) within 80 km.

3 km
139 m
16 km
198 m
80 km
568 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Presidente Franco 5.0 km · Foz do Iguacu 6.0 km · Ciudad del Este 13 km · Santa Terezinha de Itaipu 25 km · Colonia Wanda 42 km · São Miguel do Iguaçu 44 km · Puerto Esperanza 47 km · Medianeira 59 km

Argentina travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / I
220 V · 50 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$14,898
2025
Happiness
6.4 / 10
World Happiness, 2025
Homicide rate
4.5
per 100k, 2023
Road deaths
14.1
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
High
EF EPI 575
Religion
Roman Catholic 63%none 19%Evangelical 15%Jehovah's Witness and Church of Jesus Christ 1%

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 Iguazu (-25.5991°, -54.5735°, elevation 177 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).