Formoso do Araguaia weather in September

In September, Formoso do Araguaia sees average daytime highs of 36°C and overnight lows near 24°C, with 19 mm of rain across 3.2 wet days and about 11.9 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 54% of the time in September, and the air most often feels dry.

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 Formoso do Araguaia's 4th-clearest and 4th-windiest month. For the whole year in context, see Formoso do Araguaia's year-round climate.

Daytime high
36°
1st warmest
Overnight low
24°
12th coldest
Rainfall
19 mm
3.2 wet days
Daylight
11 h 54 min
6:14 AM – 6:11 PM
Cloud cover
41%
4th clearest
Wind
9 km/h
4th windiest
Solar energy
6.06 kWh/m²
Travel score
2.4
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 Formoso do Araguaia reaches about 36°C in the afternoon and slips back to 24°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 38°C. Set against its neighbours, September runs on par with August and about 2°C warmer than October.

20°25°30°35°40°151015202530
Avg high (°C)Avg low (°C)
13624
23624
33624
43624
53624
63624
73624
83624
93624
103624
113624
123624
133624
143624
153624
163624
173624
183624
193624
203624
213624
223624
233624
243624
253624
263524
273524
283524
293524
303524

How September really feels in Formoso do Araguaia

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.

Formoso do Araguaia 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°29126.412.62.9
Feb31° / 23°25623.612.42.8
Mar31° / 23°26325.512.12.9
Apr32° / 23°1501711.73.4
May33° / 23°314.911.54.1
Jun33° / 22°20.411.34.5
Jul34° / 21°0011.44.3
Aug35° / 23°10.311.63.2
Sep36° / 24°193.211.92.4
Oct34° / 24°10914.312.32.7
Nov32° / 23°21822.112.52.9
Dec31° / 23°26224.612.72.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 54% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 19% of September, with mostly cloudy or overcast conditions the remaining 27%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18218
28218
38119
48119
58119
68020
78020
88020
97921
107921
117822
127822
137723
147624
157624
167525
177525
187327
197327
207129
217030
226931
236832
246733
256634
266436
276337
286238
296040
305941

Chance of precipitation in September

Any precipitation

Formoso do Araguaia gets around 19 mm of rain over 3.2 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 11% 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 (%)
14
24
35
45
55
65
75
85
95
106
116
126
136
147
157
168
179
1810
1911
2012
2114
2215
2317
2418
2520
2622
2724
2825
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 24% of days. Sticky, muggy-or-worse air turns up on roughly 34% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1392920112
2392820112
3392819123
4382719123
5382719134
6382718134
7372718144
8362718145
9362718155
10352718165
11332618166
12322618176
13302619187
14292619197
15272520208
16252421209
172424212110
182223222311
192021222413
201820232514
211619232716
221417232817
231216233019
241115233121
25913223223
26812213326
27711213428
28611203430
29510193532
30410183534

Wind in September

Winds average 9 km/h in September.

Across September, daily wind ranges from about 7 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
110calm
29calm
39calm
49calm
59calm
69calm
79calm
89calm
99calm
109calm
119calm
129calm
139calm
149calm
159calm
169calm
179calm
188calm
198calm
208calm
218calm
228calm
238calm
248calm
258calm
267calm
277calm
287calm
297calm
307calm

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 6:25 AM to 6:05 AM, and sunset from 6:11 PM to 6:10 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.86:256:11
211.86:246:11
311.86:236:11
411.86:236:11
511.86:226:11
611.86:216:11
711.86:216:11
811.86:206:11
911.96:196:11
1011.96:196:11
1111.96:186:11
1211.96:176:11
1311.96:166:11
1411.96:166:11
1511.96:156:11
1611.96:146:11
1711.96:146:10
1812.06:136:10
1912.06:126:10
2012.06:126:10
2112.06:116:10
2212.06:106:10
2312.06:096:10
2412.06:096:10
2512.06:086:10
2612.06:076:10
2712.16:076:10
2812.16:066:10
2912.16:056:10
3012.16:056:10

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.06 kWh/m² — the sunniest month for solar.

For context, solar energy here swings from a low near 4.88 kWh/m² to a high of 6.06 kWh/m² in September across the year — September's 6.06 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.0Bright
26.0Bright
36.0Bright
46.0Intense
56.0Intense
66.0Intense
76.0Intense
86.1Intense
96.1Intense
106.1Intense
116.1Intense
126.1Intense
136.1Intense
146.1Intense
156.1Intense
166.1Intense
176.1Intense
186.1Intense
196.1Intense
206.1Intense
216.0Intense
226.0Intense
236.0Intense
246.0Intense
256.0Intense
266.0Intense
276.0Bright
286.0Bright
296.0Bright
306.0Bright
Planning a trip in September

Hazard calendar for Formoso do Araguaia

In seasonPeak

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

Formoso do Araguaia's monsoon runs November–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 Formoso do Araguaia?

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

2.4
Sightseeing
12th-best month of the year
5.8
Beach & pool
5th-best month of the year

September is a weaker month for outdoor sightseeing in Formoso do Araguaia.

What to pack for Formoso do Araguaia in September

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

In September, Formoso do Araguaia sees daytime highs around 36°C and nights near 24°C. Pack light clothes and sun protection. About 3 days see rain.

light clothessun protection

UV index in Formoso do Araguaia 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 Formoso do Araguaia peaks around February 14 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 22 at about 8 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeFeb 14UV 15Jun 22UV 8
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar14Extreme
Apr12Extreme
May10Very high
Jun8Very high
Jul9Very high
Aug10Very high
Sep12Extreme
Oct10Extreme
Nov12Extreme
Dec12Extreme

Air quality in Formoso do Araguaia 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 Formoso do Araguaia is worst in September — around 27 µg/m³ PM2.5 (moderate), about 6.9× the cleanest month (June, 4 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodSep 2327 µg/m³Jun 224 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb8Good
Mar9Good
Apr8Good
May8Good
Jun4Good
Jul5Good
Aug8Good
Sep27Moderate
Oct26Moderate
Nov11Good
Dec9Good
Location & terrain

Where is Formoso do Araguaia?

Formoso do Araguaia sits at 11.8°S, 49.5°W, 247 m above sea level, in Brazil. The nearest listed city is Gurupi, 51 km away.

Topography around Formoso do Araguaia

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Formoso do Araguaia.

Within 3 km, the terrain around Formoso do Araguaia has only modest variations in elevation — a maximum elevation change of 62 m around an average of 252 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 103 m; within 80 km, significant variations in elevation — a maximum elevation change of 398 m.

The land around Formoso do Araguaia is covered by grassland (42%) and trees (33%) within 3 km, grassland (44%) and trees (40%) within 16 km, and grassland (46%) and trees (43%) within 80 km.

3 km
62 m
16 km
103 m
80 km
398 m
treesshrubsgrasslandcroplandartificial surfaceswaterwetland
September weather nearby: Gurupi 51 km · Lagoa da Confusão 112 km · Porto Nacional 171 km · São Miguel do Araguaia 178 km · Porangatu 187 km · Paraíso do Tocantins 194 km · Palmas 224 km · Minaçu 240 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 Formoso do Araguaia (-11.7967°, -49.5289°, elevation 247 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).