São Lourenço da Serra weather in September

In September, São Lourenço da Serra sees average daytime highs of 23°C and overnight lows near 14°C, with 107 mm of rain across 11.1 wet days and about 11.9 hours of daylight. It is the 8th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 23°C through the month. The sky is clear or mostly clear about 29% of the time in September, and the air most often feels comfortable.

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 São Lourenço da Serra's 6th-clearest and 1st-windiest month. For the whole year in context, see São Lourenço da Serra's year-round climate.

Daytime high
23°
8th warmest
Overnight low
14°
5th coldest
Rainfall
107 mm
11.1 wet days
Daylight
11 h 54 min
7:06 AM – 6:58 PM
Cloud cover
65%
6th clearest
Wind
11 km/h
1st windiest
Solar energy
4.6 kWh/m²
Travel score
6.6
out of 10

São Lourenço da Serra 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 23°C through the month.

A typical September day in São Lourenço da Serra reaches about 23°C in the afternoon and slips back to 14°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 17°C and 29°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)
12313
22313
32313
42313
52313
62314
72314
82314
92314
102314
112314
122314
132314
142314
152314
162314
172314
182314
192314
202314
212314
222314
232314
242314
252314
262314
272314
282314
292314
302315

São Lourenço da Serra weather by month

How September compares with the rest of the year at a glance. September is the 8th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan26° / 19°29225.913.34.1
Feb27° / 19°23822.212.84.3
Mar26° / 18°20922.812.24.7
Apr24° / 16°9113.411.56.2
May22° / 14°739.510.96.7
Jun21° / 13°616.810.67.1
Jul21° / 12°646.610.77.1
Aug22° / 12°506.411.27.4
Sep23° / 14°10711.111.96.6
Oct24° / 15°1441712.65.6
Nov24° / 16°18819.213.25.2
Dec26° / 18°22923.113.44.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 29% 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 61%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15545
25446
35347
45248
55149
64951
74852
84753
94654
104555
114456
124258
134159
144159
153961
163763
173664
183664
193565
203466
213367
223169
233169
243070
252971
262971
272872
282674
292674
302674

Chance of precipitation in September

Any precipitation

São Lourenço da Serra gets around 107 mm of rain over 11.1 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 37% and peaks near 50% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
126
227
327
428
528
629
729
830
930
1031
1131
1232
1332
1433
1534
1635
1736
1837
1939
2040
2141
2243
2344
2445
2546
2647
2748
2849
2949
3050

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the comfortable band about 47% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)
14147120
24147120
34047130
43947140
53847150
63747160
73647170
83548170
93448180
103248190
113149200
123049210
132849220
142750230
152650240
162551240
172451250
182450260
192349271
202249281
212248291
222148301
232047311
242046322
251945332
261945342
271844353
281843373
291742383
301741394

Wind in September

Winds average 11 km/h in September, the windiest month of the year.

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
811calm
911calm
1011calm
1111calm
1211calm
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 7:22 AM to 6:51 AM, and sunset from 6:53 PM to 7:03 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.57:226:53
211.57:216:53
311.67:206:54
411.67:196:54
511.67:186:54
611.67:176:55
711.77:166:55
811.77:156:55
911.77:146:56
1011.77:136:56
1111.77:126:56
1211.87:116:57
1311.87:096:57
1411.87:086:57
1511.87:076:58
1611.97:066:58
1711.97:056:58
1811.97:046:59
1911.97:036:59
2012.07:026:59
2112.07:017:00
2212.07:007:00
2312.06:597:00
2412.16:587:01
2512.16:567:01
2612.16:557:01
2712.16:547:02
2812.16:537:02
2912.26:527:03
3012.26:517:03

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.6 kWh/m².

For context, solar energy here swings from a low near 3.23 kWh/m² to a high of 5.67 kWh/m² in December across the year — September's 4.6 kWh/m² falls in the middle.

024151015202530
Solar energy (kWh/m²)Level
14.6Bright
24.6Bright
34.6Bright
44.6Bright
54.6Bright
64.6Bright
74.6Bright
84.6Bright
94.6Bright
104.6Bright
114.6Bright
124.6Bright
134.6Bright
144.6Bright
154.6Bright
164.6Bright
174.6Bright
184.6Bright
194.6Bright
204.6Bright
214.6Bright
224.6Bright
234.6Bright
244.6Bright
254.6Bright
264.6Bright
274.7Bright
284.7Bright
294.7Bright
304.7Bright
Planning a trip in September

Hazard calendar for São Lourenço da Serra

In seasonPeak

None of São Lourenço da Serra's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

São Lourenço da Serra's rainy season runs October–March, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit São Lourenço da Serra?

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

6.6
Sightseeing
5th-best month of the year
5.2
Beach & pool
3rd-best month of the year

September is a reasonable time to visit São Lourenço da Serra for sightseeing.

What to pack for São Lourenço da Serra in September

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

In September, São Lourenço da Serra sees daytime highs around 23°C and nights near 14°C. Worth packing: light clothes, rain gear and sun protection. About 11 days see rain.

light clothesrain gearsun protection

Sea temperature near São Lourenço da Serra in September

The nearest coast averages about 21°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 44 km away) is warmest in February at about 27°C and coldest in August near 20°C.

The water stays above 20°C all year — warm enough for a swim any month.

20°25°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr26Warm
May24Refreshing
Jun22Refreshing
Jul21Refreshing
Aug20Refreshing
Sep21Refreshing
Oct22Refreshing
Nov23Refreshing
Dec25Warm

UV index in São Lourenço da Serra in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 7 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in São Lourenço da Serra peaks around January 23 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 12 at about 5 (high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highHighVery highExtremeJan 23UV 14Jul 12UV 5
UV index (midday)Level
Jan14Extreme
Feb14Extreme
Mar9Very high
Apr8Very high
May7High
Jun6High
Jul5Moderate
Aug7High
Sep7Very high
Oct10Extreme
Nov13Extreme
Dec13Extreme

Air quality in São Lourenço da Serra 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 São Lourenço da Serra is worst in July — around 33 µg/m³ PM2.5 (moderate), about 2.0× the cleanest month (January, 17 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateJul 2033 µg/m³Jan 1817 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb17Moderate
Mar18Moderate
Apr20Moderate
May24Moderate
Jun30Moderate
Jul33Moderate
Aug32Moderate
Sep29Moderate
Oct21Moderate
Nov17Moderate
Dec17Moderate
Location & terrain

Where is São Lourenço da Serra?

São Lourenço da Serra sits at 23.9°S, 46.9°W, 706 m above sea level, in Brazil. The nearest listed city is Embu-Guaçu, 14 km away.

Topography around São Lourenço da Serra

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of São Lourenço da Serra.

Within 3 km, the terrain around São Lourenço da Serra has only modest variations in elevation — a maximum elevation change of 184 m around an average of 759 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 417 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,416 m.

The land around São Lourenço da Serra is covered by trees (87%) within 3 km, trees (90%) within 16 km, and trees (59%) within 80 km.

3 km
184 m
16 km
417 m
80 km
1,416 m
treesgrasslandcroplandartificial surfaceswatermangroves
September weather nearby: Embu-Guaçu 14 km · Juquitiba 16 km · Itapecerica da Serra 18 km · Parelheiros 22 km · Jardim Angela 23 km · Embu das Artes 24 km · Capao Redondo 26 km · Cotia 28 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 São Lourenço da Serra (-23.8525°, -46.9425°, elevation 706 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).