Chaves weather in September

In September, Chaves sees average daytime highs of 32°C and overnight lows near 24°C, with 33 mm of rain across 10.3 wet days and about 12 hours of daylight. It is the 3rd-warmest and 11th-wettest month of the year here.

Day-to-day highs hold fairly steady near 32°C through the month. The sky is clear or mostly clear about 59% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 12 hours at the start of September to 12 hours by month's end. Set against the rest of the year, September is Chaves's 1st-clearest and 2nd-windiest month. For the whole year in context, see Chaves's year-round climate.

Daytime high
32°
3rd warmest
Overnight low
24°
10th coldest
Rainfall
33 mm
10.3 wet days
Daylight
12 hours
6:14 AM – 6:14 PM
Cloud cover
41%
1st clearest
Wind
12 km/h
2nd windiest
Solar energy
6.16 kWh/m²
Travel score
3.9
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 32°C through the month.

A typical September day in Chaves reaches about 32°C in the afternoon and slips back to 24°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 31°C and 33°C. Set against its neighbours, September runs on par with August and on par with October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13224
23224
33224
43224
53224
63224
73224
83224
93224
103224
113224
123224
133224
143224
153224
163224
173324
183324
193324
203324
213324
223324
233324
243324
253324
263325
273325
283325
293325
303325

How September really feels in Chaves

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.

Chaves weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 11th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 24°31029.5122.8
Feb29° / 24°39127.3122.9
Mar29° / 24°44730.3122.8
Apr29° / 24°42329.4122.7
May30° / 24°33129.2122.8
Jun31° / 24°15825.3123.0
Jul31° / 24°12223.5123.3
Aug32° / 24°6118123.5
Sep32° / 24°3310.3123.9
Oct33° / 25°256.3124.0
Nov33° / 25°429123.8
Dec31° / 24°14321.9123.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 59% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 23% of September, with mostly cloudy or overcast conditions the remaining 17%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18515
28416
38416
48515
58515
68515
78515
88416
98416
108416
118515
128416
138416
148416
158416
168317
178317
188218
198218
208218
218119
228119
238119
248119
258119
268020
278020
288020
297921
307921

Chance of precipitation in September

Any precipitation

Chaves gets around 33 mm of rain over 10.3 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 35% and peaks near 47% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
147
247
346
446
545
644
744
843
942
1041
1140
1239
1338
1437
1535
1634
1733
1831
1930
2029
2128
2227
2326
2425
2524
2624
2723
2823
2922
3022

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 90% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
18317
28416
38515
48614
58614
68713
78713
88713
98812
108812
118812
128911
138911
148911
159010
169010
17919
18928
19928
20937
21937
22946
23946
24955
25955
26955
27964
28964
29964
30964

Wind in September

Winds average 12 km/h in September.

Across September, daily wind ranges from about 11 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
512calm
612calm
712calm
812calm
912calm
1012calm
1112calm
1212calm
1312calm
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 hours 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 0 minutes over September. Sunrise moves from 6:20 AM to 6:09 AM, and sunset from 6:20 PM to 6:09 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.06:206:20
212.06:196:19
312.06:196:19
412.06:196:19
512.06:186:18
612.06:186:18
712.06:186:18
812.06:176:17
912.06:176:17
1012.06:176:16
1112.06:166:16
1212.06:166:16
1312.06:156:15
1412.06:156:15
1512.06:156:15
1612.06:146:14
1712.06:146:14
1812.06:146:14
1912.06:136:13
2012.06:136:13
2112.06:126:12
2212.06:126:12
2312.06:126:12
2412.06:116:11
2512.06:116:11
2612.06:116:11
2712.06:106:10
2812.06:106:10
2912.06:106:10
3012.06:096:09

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.16 kWh/m².

For context, solar energy here swings from a low near 3.77 kWh/m² to a high of 6.26 kWh/m² in October across the year — September's 6.16 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.0Bright
26.0Bright
36.0Bright
46.0Bright
56.0Intense
66.0Intense
76.0Intense
86.0Intense
96.1Intense
106.1Intense
116.1Intense
126.1Intense
136.1Intense
146.1Intense
156.2Intense
166.2Intense
176.2Intense
186.2Intense
196.2Intense
206.2Intense
216.2Intense
226.2Intense
236.3Intense
246.3Intense
256.3Intense
266.3Intense
276.3Intense
286.3Intense
296.3Intense
306.3Intense
Planning a trip in September

Hazard calendar for Chaves

In seasonPeak

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

Chaves's monsoon runs January–May, 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 Chaves?

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

3.9
Sightseeing
2nd-best month of the year
6.5
Beach & pool
2nd-best month of the year

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

What to pack for Chaves in September

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

In September, Chaves sees daytime highs around 32°C and nights near 24°C. Pack light clothes and sun protection. Worth having: rain gear. About 10 days see rain.

light clothessun protectionrain gear

Sea temperature near Chaves in September

The nearest coast averages about 29°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 13 km away) is warmest in October at about 30°C and coldest in March near 28°C.

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

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan29Tropical
Feb28Tropical
Mar28Tropical
Apr28Tropical
May29Tropical
Jun29Tropical
Jul29Tropical
Aug29Tropical
Sep29Tropical
Oct30Tropical
Nov30Tropical
Dec29Tropical

UV index in Chaves 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 Chaves peaks around March 13 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near August 11 at about 10 (extreme).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeMar 13UV 15Aug 11UV 10
UV index (midday)Level
Jan14Extreme
Feb15Extreme
Mar15Extreme
Apr14Extreme
May12Extreme
Jun11Extreme
Jul11Extreme
Aug10Extreme
Sep12Extreme
Oct12Extreme
Nov11Extreme
Dec11Extreme

Air quality in Chaves 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 Chaves is worst in February — around 21 µg/m³ PM2.5 (moderate), about 3.3× the cleanest month (July, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodModerateFeb 2021 µg/m³Jul 177 µg/m³
PM2.5 (µg/m³)Level
Jan17Moderate
Feb21Moderate
Mar21Moderate
Apr17Moderate
May9Good
Jun7Good
Jul7Good
Aug7Good
Sep9Good
Oct12Good
Nov12Moderate
Dec14Moderate
Location & terrain

Where is Chaves?

Chaves sits at 0.2°S, 50.0°W, 0 m above sea level, in Brazil. The nearest listed city is Afuá, 44 km away.

Topography around Chaves

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

Within 3 km, the terrain around Chaves has only modest variations in elevation — a maximum elevation change of 25 m around an average of 6 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 32 m; within 80 km, only modest variations in elevation — a maximum elevation change of 39 m.

The land around Chaves is covered by water (55%) and trees (38%) within 3 km, water (44%) and trees (38%) within 16 km, and trees (54%) and water (27%) within 80 km.

3 km
25 m
16 km
32 m
80 km
39 m
treesgrasslandwaterwetland
September weather nearby: Afuá 44 km · Anajás 92 km · Macapá 122 km · Santana 133 km · Mazagão 145 km · Cachoeira do Arari 148 km · Soure 174 km · Muaná 175 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 Chaves (-0.16°, -49.9883°, elevation 0 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).