Juan José Castelli weather in September

In September, Juan José Castelli sees average daytime highs of 28°C and overnight lows near 15°C, with 58 mm of rain across 6.7 wet days and about 11.8 hours of daylight. It is the 7th-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 56% of the time in September, and the air most often feels dry.

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 Juan José Castelli's 2nd-clearest and 2nd-windiest month. For the whole year in context, see Juan José Castelli's year-round climate.

Daytime high
28°
7th warmest
Overnight low
15°
5th coldest
Rainfall
58 mm
6.7 wet days
Daylight
11 h 48 min
7:01 AM – 6:52 PM
Cloud cover
41%
2nd clearest
Wind
13 km/h
2nd windiest
Solar energy
4.9 kWh/m²
Travel score
7.0
out of 10

Juan José Castelli is human settlement.

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 28°C through the month.

A typical September day in Juan José Castelli reaches about 28°C in the afternoon and slips back to 15°C overnight — a 13°C spread between the day's warmth and the night's chill. On most days the high lands between 19°C and 37°C. Set against its neighbours, September runs about 3°C warmer than August and about 2°C cooler than October.

10°20°30°40°151015202530
Avg high (°C)Avg low (°C)
12714
22714
32714
42714
52714
62715
72715
82715
92715
102715
112715
122715
132815
142815
152815
162815
172815
182815
192815
202815
212815
222815
232816
242816
252816
262816
272816
282816
292916
302916

How September really feels in Juan José Castelli

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.

Juan José Castelli weather by month

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

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan33° / 23°12411.213.43.3
Feb32° / 22°13711.112.93.8
Mar30° / 21°13711.112.24.8
Apr27° / 18°1179.311.46.5
May24° / 14°627.810.77.2
Jun22° / 13°436.810.47.1
Jul22° / 11°315.810.57.6
Aug25° / 13°404.511.18.1
Sep28° / 15°586.711.87.0
Oct30° / 18°1201012.65.2
Nov31° / 20°14010.113.34.6
Dec33° / 22°13511.113.63.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 56% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 10% of September, with mostly cloudy or overcast conditions the remaining 34%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
17228
27228
37228
47228
57129
67030
77030
86931
96931
106931
116832
126832
136832
146832
156733
166634
176634
186634
196535
206535
216337
226337
236238
246238
256040
266040
275941
285842
295842
305743

Chance of precipitation in September

Any precipitation

Juan José Castelli gets around 58 mm of rain over 6.7 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 22% and peaks near 28% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%151015202530
Rain chance (%)
115
216
316
417
518
618
719
820
920
1021
1121
1222
1322
1423
1523
1624
1724
1824
1924
2024
2125
2225
2325
2425
2526
2626
2727
2827
2927
3028

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 55% of days. Sticky, muggy-or-worse air turns up on roughly 9% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
162201260
262201260
361201270
460211270
560211270
660211270
760211270
860211270
959221270
1059221270
1159221270
1259221270
1358221370
1458221370
1558221370
1657221470
1758211470
1857211570
1956201581
2055201681
2154201691
2254191791
23521918101
24511918111
25501919111
26481920121
27471820131
28461821141
29451821141
30441822151

Wind in September

Winds average 13 km/h in September.

Across September, daily wind ranges from about 13 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
613light breeze
713light breeze
813light breeze
913light breeze
1013light breeze
1113light breeze
1213light breeze
1313light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1913light breeze
2013light breeze
2113light breeze
2213light breeze
2313light breeze
2413light breeze
2513light breeze
2613light breeze
2713light breeze
2813light breeze
2913light breeze
3013light breeze

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 7:18 AM to 6:45 AM, and sunset from 6:46 PM to 6:58 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.57:186:46
211.57:176:47
311.57:166:47
411.57:156:47
511.67:146:48
611.67:136:48
711.67:126:49
811.67:106:49
911.77:096:49
1011.77:086:50
1111.77:076:50
1211.77:066:51
1311.87:056:51
1411.87:046:51
1511.87:026:52
1611.87:016:52
1711.97:006:53
1811.96:596:53
1911.96:586:54
2012.06:576:54
2112.06:566:54
2212.06:546:55
2312.06:536:55
2412.16:526:56
2512.16:516:56
2612.16:506:56
2712.16:496:57
2812.26:486:57
2912.26:466:58
3012.26:456:58

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.9 kWh/m².

For context, solar energy here swings from a low near 2.67 kWh/m² to a high of 6.73 kWh/m² in December across the year — September's 4.9 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.7Bright
54.7Bright
64.7Bright
74.7Bright
84.8Bright
94.8Bright
104.8Bright
114.8Bright
124.9Bright
134.9Bright
144.9Bright
154.9Bright
165.0Bright
175.0Bright
185.0Bright
195.0Bright
205.0Bright
215.1Bright
225.1Bright
235.1Bright
245.1Bright
255.1Bright
265.1Bright
275.2Bright
285.2Bright
295.2Bright
305.2Bright
Planning a trip in September

Is September a good time to visit Juan José Castelli?

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

7.0
Sightseeing
5th-best month of the year
7.5
Beach & pool
1st-best month of the year

September is one of the better times to visit Juan José Castelli for general sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Juan José Castelli in September

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

In September, Juan José Castelli sees daytime highs around 28°C and nights near 15°C. Pack light clothes. Worth having: sun protection. About 7 days see rain.

light clothessun protection

UV index in Juan José Castelli 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 Juan José Castelli peaks around January 18 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 11 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 18UV 14Jul 11UV 5
UV index (midday)Level
Jan15Extreme
Feb14Extreme
Mar12Extreme
Apr9Very high
May6High
Jun5Moderate
Jul5Moderate
Aug6High
Sep8Very high
Oct7High
Nov12Extreme
Dec14Extreme

Air quality in Juan José Castelli 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 Juan José Castelli is worst in August — around 31 µg/m³ PM2.5 (moderate), about 5.1× the cleanest month (April, 6 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodAug 2330 µg/m³Apr 236 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar8Good
Apr6Good
May6Good
Jun7Good
Jul15Moderate
Aug31Moderate
Sep29Moderate
Oct18Moderate
Nov10Good
Dec9Good
Location & terrain

Where is Juan José Castelli?

Juan José Castelli sits at 25.9°S, 60.6°W, 113 m above sea level, in Argentina. The nearest listed city is Tres Isletas, 48 km away.

Topography around Juan José Castelli

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

Within 3 km, the terrain around Juan José Castelli has only modest variations in elevation — a maximum elevation change of 9 m around an average of 110 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 20 m; within 80 km, only modest variations in elevation — a maximum elevation change of 64 m.

The land around Juan José Castelli is covered by cropland (30%), artificial surfaces (29%) and grassland (22%) within 3 km, trees (56%) and cropland (30%) within 16 km, and trees (75%) within 80 km.

3 km
9 m
16 km
20 m
80 km
64 m
treesshrubsgrasslandcroplandartificial surfaces
September weather nearby: Tres Isletas 48 km · Presidencia Roque Sáenz Peña 96 km · Quitilipi 110 km · Machagai 123 km · Las Breñas 135 km · General José de San Martín 143 km · Charata 152 km · Pirané 153 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 Juan José Castelli (-25.9466°, -60.6201°, elevation 113 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).