Barão de Grajaú weather in September

In September, Barão de Grajaú sees average daytime highs of 36°C and overnight lows near 25°C, with 4 mm of rain across 0.5 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 36°C through the month. The sky is clear or mostly clear about 78% of the time in September, and the air most often feels comfortable.

Daylight stretches from about 11 h 54 min at the start of September to 12 h 06 min by month's end. Set against the rest of the year, September is Barão de Grajaú's 2nd-clearest and 4th-windiest month. For the whole year in context, see Barão de Grajaú's year-round climate.

Daytime high
36°
1st warmest
Overnight low
25°
10th coldest
Rainfall
4 mm
0.5 wet days
Daylight
12 hours
5:48 AM – 5:45 PM
Cloud cover
27%
2nd clearest
Wind
12 km/h
4th windiest
Solar energy
6.76 kWh/m²
Travel score
2.5
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 36°C through the month.

A typical September day in Barão de Grajaú reaches about 36°C in the afternoon and slips back to 25°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 35°C and 38°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)
13624
23624
33624
43625
53625
63625
73625
83625
93625
103625
113625
123625
133625
143625
153625
163625
173625
183625
193625
203625
213625
223625
233725
243725
253725
263725
273725
283726
293726
303726

How September really feels in Barão de Grajaú

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.

Barão de Grajaú 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
Jan32° / 23°20022.512.33.0
Feb31° / 23°19321.212.22.9
Mar31° / 23°18823.2123.0
Apr32° / 23°11215.911.93.5
May33° / 24°416.511.73.9
Jun33° / 24°40.811.64.2
Jul34° / 23°30.311.64.2
Aug35° / 24°00.111.83.4
Sep36° / 25°40.5122.5
Oct36° / 26°213.112.22.3
Nov35° / 25°749.212.32.8
Dec33° / 24°11313.712.43.1

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 78% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 12% of September, with mostly cloudy or overcast conditions the remaining 11%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
1928
2919
3919
4919
5919
69010
79010
89010
99010
109010
11919
12919
13919
149010
159010
16919
17919
189010
199010
209010
219010
229010
238812
248812
258812
268713
278713
288515
298515
308416

Chance of precipitation in September

Any precipitation

Barão de Grajaú gets around 4 mm of rain over 0.5 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 2% and peaks near 4% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
11
21
31
41
51
61
71
81
91
101
111
121
131
141
151
161
171
181
191
202
212
222
232
242
253
263
273
283
294
304

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 48% of days. Sticky, muggy-or-worse air turns up on roughly 11% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
16583150
27573150
37553260
47553260
57543360
67533370
77523470
86523471
96513571
106513571
116503671
125513671
135513671
145503781
155503781
164493781
174493791
184483791
1944838101
2034738101
2134639111
2234539112
2334439122
2434340132
2534140142
2634040152
2733940153
2823840163
2923740173
3023640183

Wind in September

Winds average 12 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 13 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
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
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812calm
1912calm
2012calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2810calm
2910calm
3010calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 54 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 12 minutes over September. Sunrise moves from 5:56 AM to 5:40 AM, and sunset from 5:48 PM to 5:43 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.95:565:48
211.95:555:48
311.95:555:48
411.95:545:47
511.95:545:47
611.95:535:47
711.95:535:47
811.95:525:47
911.95:515:47
1011.95:515:46
1111.95:505:46
1211.95:505:46
1311.95:495:46
1412.05:495:46
1512.05:485:46
1612.05:485:45
1712.05:475:45
1812.05:465:45
1912.05:465:45
2012.05:455:45
2112.05:455:44
2212.05:445:44
2312.05:445:44
2412.05:435:44
2512.05:435:44
2612.05:425:44
2712.05:415:43
2812.05:415:43
2912.05:405:43
3012.15:405:43

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.76 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 4.85 kWh/m² to a high of 6.76 kWh/m² in September across the year — September's 6.76 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.6Intense
26.6Intense
36.6Intense
46.7Intense
56.7Intense
66.7Intense
76.7Intense
86.7Intense
96.7Intense
106.7Intense
116.8Intense
126.8Intense
136.8Intense
146.8Intense
156.8Intense
166.8Intense
176.8Intense
186.8Intense
196.8Intense
206.8Intense
216.8Intense
226.8Intense
236.8Intense
246.8Intense
256.8Intense
266.8Intense
276.8Intense
286.8Intense
296.8Intense
306.8Intense
Planning a trip in September

Hazard calendar for Barão de Grajaú

In seasonPeak

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

Barão de Grajaú'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 Barão de Grajaú?

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

2.5
Sightseeing
11th-best month of the year
6.1
Beach & pool
5th-best month of the year

September is a weaker month for outdoor sightseeing in Barão de Grajaú. The water and warmth also suit a beach or pool day.

What to pack for Barão de Grajaú in September

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

In September, Barão de Grajaú sees daytime highs around 36°C and nights near 25°C. Pack light clothes and sun protection.

light clothessun protection

UV index in Barão de Grajaú 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 Barão de Grajaú peaks around March 12 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.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 12UV 15Jul 24UV 10
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar15Extreme
Apr13Extreme
May11Extreme
Jun10Very high
Jul10Very high
Aug10Very high
Sep12Extreme
Oct12Extreme
Nov12Extreme
Dec11Extreme

Air quality in Barão de Grajaú 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 Barão de Grajaú is worst in October — around 16 µg/m³ PM2.5 (moderate), about 4.9× the cleanest month (June, 3 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodOct 1815 µg/m³Jun 233 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar10Good
Apr9Good
May6Good
Jun3Good
Jul3Good
Aug6Good
Sep11Good
Oct16Moderate
Nov12Moderate
Dec11Good
Location & terrain

Where is Barão de Grajaú?

Barão de Grajaú sits at 6.8°S, 43.0°W, 119 m above sea level, in Brazil. The nearest listed city is Floriano, 1.0 km away.

Topography around Barão de Grajaú

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

Within 3 km, the terrain around Barão de Grajaú has only modest variations in elevation — a maximum elevation change of 89 m around an average of 131 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 166 m; within 80 km, significant variations in elevation — a maximum elevation change of 390 m.

The land around Barão de Grajaú is covered by artificial surfaces (32%), grassland (28%) and trees (27%) within 3 km, trees (49%) and grassland (32%) within 16 km, and trees (52%) and shrubs (30%) within 80 km.

3 km
89 m
16 km
166 m
80 km
390 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Floriano 1.0 km · Amarante 60 km · Regeneração 69 km · São João dos Patos 80 km · Oeiras 103 km · Água Branca 105 km · Passagem Franca 106 km · Paraibano 112 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 Barão de Grajaú (-6.7564°, -43.0242°, elevation 119 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).