São Domingos do Maranhão weather in September

In September, São Domingos do Maranhão sees average daytime highs of 35°C and overnight lows near 23°C, with 12 mm of rain across 1.8 wet days and about 12 hours of daylight. It is the 1st-warmest and 9th-wettest month of the year here.

Day-to-day highs hold fairly steady near 35°C through the month. The sky is clear or mostly clear about 65% of the time in September, and the air most often feels muggy.

Daylight stretches from about 11 h 54 min at the start of September to 12 hours by month's end. Set against the rest of the year, September is São Domingos do Maranhão's 2nd-clearest and 4th-windiest month. For the whole year in context, see São Domingos do Maranhão's year-round climate.

Daytime high
35°
1st warmest
Overnight low
23°
10th coldest
Rainfall
12 mm
1.8 wet days
Daylight
12 hours
5:53 AM – 5:51 PM
Cloud cover
35%
2nd clearest
Wind
8 km/h
4th windiest
Solar energy
6.42 kWh/m²
Travel score
3.0
out of 10

São Domingos do Maranhão is 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 35°C through the month.

A typical September day in São Domingos do Maranhão reaches about 35°C in the afternoon and slips back to 23°C overnight — a 12°C spread between the day's warmth and the night's chill. On most days the high lands between 33°C and 37°C. Set against its neighbours, September runs about 1°C warmer than August and on par with October.

20°25°30°35°40°151015202530
Avg high (°C)Avg low (°C)
13523
23523
33523
43523
53523
63523
73523
83523
93523
103523
113523
123523
133523
143523
153523
163523
173523
183523
193523
203523
213523
223523
233523
243523
253523
263523
273524
283524
293524
303524

How September really feels in São Domingos do Maranhão

Once humidity and wind are folded in, September averages 30 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
30
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

São Domingos do Maranhão weather by month

How September compares with the rest of the year at a glance. September is the 1st-warmest and 9th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan31° / 23°24226.212.32.9
Feb30° / 23°22824.512.22.9
Mar30° / 23°26527.9122.8
Apr30° / 23°18523.211.93.2
May31° / 23°8312.611.74.1
Jun32° / 23°112.611.74.7
Jul33° / 22°70.911.74.5
Aug34° / 23°20.411.83.8
Sep35° / 23°121.8123.0
Oct35° / 24°305.212.13.0
Nov33° / 24°8411.712.33.2
Dec32° / 23°14018.112.33.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 65% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 23% of September, with mostly cloudy or overcast conditions the remaining 12%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18911
28911
38911
48911
58911
68911
78911
88911
98911
108911
118911
128911
138911
148911
158911
168911
178911
188911
198911
208812
218812
228713
238713
248713
258614
268614
278515
288416
298416
308317

Chance of precipitation in September

Any precipitation

São Domingos do Maranhão gets around 12 mm of rain over 1.8 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 6% and peaks near 9% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
14
24
34
44
54
64
74
84
94
104
115
125
135
145
155
165
175
186
196
206
217
227
238
248
258
268
279
289
299
309

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 40% of days. Sticky, muggy-or-worse air turns up on roughly 58% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1115403212
2115403212
3115403213
4115403213
5115403113
6115403113
7115403113
8115403113
9015403213
10014403313
11014393314
12013383414
13013373514
14013363615
15012353715
16012343816
17011334017
18010314118
19010294219
2009274420
2108254621
2208234722
2307214824
2406194925
2506185026
2605175127
2704165129
2804155130
2904155031
3003145132

Wind in September

Winds average 8 km/h in September.

Across September, daily wind ranges from about 8 km/h on the calmest days to 9 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
19calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
148calm
158calm
168calm
178calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
268calm
278calm
288calm
298calm
308calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 54 min at the start of September to 12 hours by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 6 minutes over September. Sunrise moves from 6:00 AM to 5:46 AM, and sunset from 5:54 PM to 5:48 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.96:005:54
211.96:005:54
311.95:595:54
411.95:595:53
511.95:585:53
611.95:585:53
711.95:575:53
811.95:575:53
911.95:565:52
1011.95:565:52
1111.95:555:52
1211.95:555:52
1312.05:545:52
1412.05:545:51
1512.05:535:51
1612.05:535:51
1712.05:525:51
1812.05:525:51
1912.05:515:50
2012.05:515:50
2112.05:505:50
2212.05:505:50
2312.05:495:49
2412.05:495:49
2512.05:485:49
2612.05:485:49
2712.05:475:49
2812.05:475:49
2912.05:465:48
3012.05:465:48

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.42 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 4.45 kWh/m² to a high of 6.42 kWh/m² in September across the year — September's 6.42 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.3Intense
26.3Intense
36.3Intense
46.3Intense
56.4Intense
66.4Intense
76.4Intense
86.4Intense
96.4Intense
106.4Intense
116.4Intense
126.4Intense
136.4Intense
146.4Intense
156.4Intense
166.4Intense
176.4Intense
186.4Intense
196.4Intense
206.4Intense
216.4Intense
226.4Intense
236.4Intense
246.4Intense
256.4Intense
266.4Intense
276.4Intense
286.4Intense
296.4Intense
306.4Intense
Planning a trip in September

Hazard calendar for São Domingos do Maranhão

In seasonPeak

None of São Domingos do Maranhão'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 Domingos do Maranhão's monsoon runs December–April, when most of the year's rain falls.

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

Is September a good time to visit São Domingos do Maranhão?

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

3.0
Sightseeing
8th-best month of the year
6.7
Beach & pool
4th-best month of the year

September is a weaker month for outdoor sightseeing in São Domingos do Maranhão. The water and warmth also suit a beach or pool day.

What to pack for São Domingos do Maranhão in September

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

In September, São Domingos do Maranhão sees daytime highs around 35°C and nights near 23°C. Pack light clothes and sun protection.

light clothessun protection

UV index in São Domingos do Maranhão 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 Domingos do Maranhão peaks around March 11 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 24 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeExtremeMar 11UV 15Jul 24UV 10
UV index (midday)Level
Jan13Extreme
Feb15Extreme
Mar15Extreme
Apr14Extreme
May11Extreme
Jun10Extreme
Jul10Very high
Aug10Very high
Sep12Extreme
Oct12Extreme
Nov12Extreme
Dec11Extreme

Air quality in São Domingos do Maranhão 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 Domingos do Maranhão is worst in October — around 55 µg/m³ PM2.5 (unhealthy), about 6.3× the cleanest month (June, 9 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModeratePoorModerateOct 1752 µg/m³Jun 199 µg/m³
PM2.5 (µg/m³)Level
Jan14Moderate
Feb14Moderate
Mar13Moderate
Apr12Good
May10Good
Jun9Good
Jul9Good
Aug18Moderate
Sep27Moderate
Oct55Unhealthy
Nov30Moderate
Dec22Moderate
Location & terrain

Where is São Domingos do Maranhão?

São Domingos do Maranhão sits at 5.6°S, 44.4°W, 179 m above sea level, in Brazil. The nearest listed city is Fortuna, 31 km away.

Topography around São Domingos do Maranhão

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

Within 3 km, the terrain around São Domingos do Maranhão has only modest variations in elevation — a maximum elevation change of 63 m around an average of 188 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 172 m; within 80 km, significant variations in elevation — a maximum elevation change of 443 m.

The land around São Domingos do Maranhão is covered by grassland (49%) and trees (37%) within 3 km, grassland (49%) and trees (45%) within 16 km, and trees (65%) and grassland (31%) within 80 km.

3 km
63 m
16 km
172 m
80 km
443 m
treesshrubsgrasslandcroplandartificial surfaceswater
September weather nearby: Fortuna 31 km · Presidente Dutra 34 km · Tuntum 46 km · Colinas 52 km · Dom Pedro 60 km · Buriti Bravo 68 km · São João do Soter 82 km · Mirador 88 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 Domingos do Maranhão (-5.5758°, -44.3853°, 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).