São Cristóvão weather in September

In September, São Cristóvão sees average daytime highs of 26°C and overnight lows near 22°C, with 64 mm of rain across 17.2 wet days and about 11.9 hours of daylight. It is the 10th-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 26°C through the month. The sky is clear or mostly clear about 54% of the time in September, and the air most often feels muggy.

Daylight stretches from about 11 h 48 min at the start of September to 12 h 06 min by month's end. Set against the rest of the year, September is São Cristóvão's 1st-clearest and 4th-windiest month. For the whole year in context, see São Cristóvão's year-round climate.

Daytime high
26°
10th warmest
Overnight low
22°
3rd coldest
Rainfall
64 mm
17.2 wet days
Daylight
11 h 54 min
5:25 AM – 5:21 PM
Cloud cover
41%
1st clearest
Wind
16 km/h
4th windiest
Solar energy
5.5 kWh/m²
Travel score
5.8
out of 10

São Cristóvão 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 26°C through the month.

A typical September day in São Cristóvão reaches about 26°C in the afternoon and slips back to 22°C overnight — a 4°C spread between the day's warmth and the night's chill. On most days the high lands between 25°C and 27°C. Set against its neighbours, September runs on par with August and about 1°C cooler than October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12622
22622
32622
42622
52622
62622
72622
82622
92622
102622
112622
122622
132622
142622
152622
162622
172622
182622
192623
202623
212623
222623
232623
242623
252623
262623
272723
282723
292723
302723

How September really feels in São Cristóvão

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.

São Cristóvão weather by month

How September compares with the rest of the year at a glance. September is the 10th-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 24°5615.212.65.2
Feb29° / 25°6316.412.44.8
Mar29° / 25°7118.112.14.7
Apr28° / 25°11220.311.84.6
May27° / 24°15722.911.54.8
Jun26° / 23°1482411.44.7
Jul25° / 22°12523.911.44.9
Aug25° / 22°9822.111.65.2
Sep26° / 22°6417.211.95.8
Oct27° / 23°5213.912.26.2
Nov28° / 24°4111.112.56.3
Dec28° / 24°3310.112.65.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 54% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 32% of September, with mostly cloudy or overcast conditions the remaining 14%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18416
28416
38416
48416
58317
68416
78416
88416
98416
108416
118416
128515
138515
148515
158614
168614
178614
188713
198713
208812
218812
228812
238911
248911
258911
268911
278713
288713
298713
308515

Chance of precipitation in September

Any precipitation

São Cristóvão gets around 64 mm of rain over 17.2 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 58% and peaks near 64% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
164
264
364
464
564
664
763
863
963
1063
1163
1262
1362
1461
1560
1659
1758
1857
1956
2055
2154
2253
2352
2451
2550
2649
2748
2847
2947
3046

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the muggy band about 72% of days. Sticky, muggy-or-worse air turns up on roughly 97% of them.

0%25%50%75%100%151015202530
Humid (%)Muggy (%)Oppressive (%)
158015
257916
357916
457817
557817
657718
747818
847719
947719
1047620
1137720
1237621
1337522
1427622
1527523
1627424
1727424
1827325
1927226
2017227
2117128
2217029
2316831
2416732
2516534
2616435
2716336
2816138
2916039
3015940

Wind in September

Winds average 16 km/h in September.

Across September, daily wind ranges from about 16 km/h on the calmest days to 16 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
116light breeze
216light breeze
316light breeze
416light breeze
516light breeze
616light breeze
716light breeze
816light breeze
916light breeze
1016light breeze
1116light breeze
1216light breeze
1316light breeze
1416light breeze
1516light breeze
1616light breeze
1716light breeze
1816light breeze
1916light breeze
2016light breeze
2116light breeze
2216light breeze
2316light breeze
2416light breeze
2516light breeze
2616light breeze
2716light breeze
2816light breeze
2916light breeze
3016light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 48 min at the start of September to 12 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 18 minutes over September. Sunrise moves from 5:35 AM to 5:16 AM, and sunset from 5:22 PM to 5:21 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.85:355:22
211.85:345:22
311.85:345:22
411.85:335:22
511.85:325:22
611.85:325:22
711.85:315:22
811.95:305:22
911.95:305:22
1011.95:295:22
1111.95:285:22
1211.95:285:22
1311.95:275:22
1411.95:265:21
1511.95:265:21
1611.95:255:21
1712.05:245:21
1812.05:245:21
1912.05:235:21
2012.05:225:21
2112.05:225:21
2212.05:215:21
2312.05:205:21
2412.05:205:21
2512.05:195:21
2612.05:185:21
2712.15:185:21
2812.15:175:21
2912.15:165:21
3012.15:165:21

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.5 kWh/m².

For context, solar energy here swings from a low near 4 kWh/m² to a high of 6.46 kWh/m² in December across the year — September's 5.5 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.1Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.2Bright
75.3Bright
85.3Bright
95.3Bright
105.3Bright
115.3Bright
125.4Bright
135.4Bright
145.4Bright
155.5Bright
165.5Bright
175.5Bright
185.6Bright
195.6Bright
205.6Bright
215.7Bright
225.7Bright
235.7Bright
245.7Bright
255.8Bright
265.8Bright
275.8Bright
285.8Bright
295.9Bright
305.9Bright
Planning a trip in September

Hazard calendar for São Cristóvão

In seasonPeak

None of São Cristóvão'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 Cristóvão's rainy season runs March–August, 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 Cristóvão?

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

5.8
Sightseeing
4th-best month of the year
5.6
Beach & pool
7th-best month of the year

September is a reasonable time to visit São Cristóvão for sightseeing.

What to pack for São Cristóvão in September

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

In September, São Cristóvão sees daytime highs around 26°C and nights near 22°C. Pack rain gear. Worth having: light clothes and sun protection. About 17 days see rain.

rain gearlight clothessun protection

Sea temperature near São Cristóvão in September

The nearest coast averages about 26°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 15 km away) is warmest in April at about 28°C and coldest in August near 26°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb28Warm
Mar28Tropical
Apr28Tropical
May28Warm
Jun27Warm
Jul26Warm
Aug26Warm
Sep26Warm
Oct26Warm
Nov26Warm
Dec27Warm

UV index in São Cristóvão in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in São Cristóvão peaks around February 16 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 10 at about 9 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeFeb 16UV 15Jul 10UV 9
UV index (midday)Level
Jan13Extreme
Feb15Extreme
Mar14Extreme
Apr13Extreme
May10Very high
Jun9Very high
Jul9Very high
Aug10Very high
Sep12Extreme
Oct12Extreme
Nov13Extreme
Dec12Extreme
Location & terrain

Where is São Cristóvão?

São Cristóvão sits at 11.0°S, 37.2°W, 38 m above sea level, in Brazil. The nearest listed city is Itaporanga d'Ajuda, 12 km away.

Topography around São Cristóvão

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

Within 3 km, the terrain around São Cristóvão has only modest variations in elevation — a maximum elevation change of 89 m around an average of 26 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 146 m; within 80 km, large variations in elevation — a maximum elevation change of 694 m.

The land around São Cristóvão is covered by trees (43%) and grassland (32%) within 3 km, trees (36%) and grassland (33%) within 16 km, and grassland (44%) and water (29%) within 80 km.

3 km
89 m
16 km
146 m
80 km
694 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
September weather nearby: Itaporanga d'Ajuda 12 km · Aracaju 19 km · Nossa Senhora do Socorro 20 km · Barra dos Coqueiros 22 km · Laranjeiras 24 km · Salgado 29 km · Areia Branca 31 km · Maruim 34 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 Cristóvão (-11.0147°, -37.2064°, elevation 38 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).