Vilhena weather in September

In September, Vilhena sees average daytime highs of 31°C and overnight lows near 21°C, with 84 mm of rain across 13.5 wet days and about 11.9 hours of daylight. It is the 2nd-warmest and 8th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 37% 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 Vilhena's 4th-clearest and 4th-windiest month. For the whole year in context, see Vilhena's year-round climate.

Daytime high
31°
2nd warmest
Overnight low
21°
6th coldest
Rainfall
84 mm
13.5 wet days
Daylight
11 h 54 min
5:57 AM – 5:53 PM
Cloud cover
53%
4th clearest
Wind
7 km/h
4th windiest
Solar energy
5.66 kWh/m²
Travel score
4.0
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 31°C through the month.

A typical September day in Vilhena reaches about 31°C in the afternoon and slips back to 21°C overnight — a 10°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 34°C. Set against its neighbours, September runs on par with August and about 1°C warmer than October.

15°20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13221
23221
33221
43221
53221
63221
73221
83221
93221
103221
113221
123121
133121
143121
153121
163121
173121
183121
193121
203121
213121
223121
233121
243121
253121
263121
273121
283121
293121
303121

How September really feels in Vilhena

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.

Vilhena weather by month

How September compares with the rest of the year at a glance. September is the 2nd-warmest and 8th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 21°26729.412.73.2
Feb28° / 21°2742712.43.3
Mar28° / 21°24128.612.13.2
Apr29° / 21°12821.511.74.0
May28° / 20°5712.111.45.5
Jun29° / 19°14311.36.6
Jul30° / 18°102.111.36.4
Aug31° / 20°244.811.65.1
Sep31° / 21°8413.511.94.0
Oct30° / 21°16522.412.33.5
Nov29° / 21°20725.612.63.3
Dec28° / 21°25928.112.73.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 37% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 24% of September, with mostly cloudy or overcast conditions the remaining 40%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
17723
27525
37327
47327
57129
67030
76931
86832
96832
106634
116634
126436
136337
146238
156040
165941
175842
185743
195644
205545
215446
225347
235248
245050
255050
264852
274852
284753
294654
304555

Chance of precipitation in September

Any precipitation

Vilhena gets around 84 mm of rain over 13.5 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 45% and peaks near 65% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
127
228
329
430
530
631
732
833
934
1035
1136
1238
1339
1441
1542
1644
1746
1848
1949
2051
2153
2255
2357
2459
2560
2662
2763
2864
2965
3065

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 47% of days. Sticky, muggy-or-worse air turns up on roughly 71% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1101627425
291526436
381526446
481426457
581325468
671324479
7712234810
8712224811
9611214912
10610204914
11610205015
1259195017
1359185018
1448175120
1547165122
1647165023
1736155125
1835145127
1935145029
2034134931
2124124833
2224124835
2323114737
2423104639
252394541
261384443
271284345
281274247
291274249
301264150

Wind in September

Winds average 7 km/h in September.

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

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
247calm
257calm
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 6:08 AM to 5:47 AM, and sunset from 5:53 PM to 5:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.86:085:53
211.86:075:53
311.86:065:53
411.86:065:53
511.86:055:53
611.86:045:53
711.86:045:53
811.86:035:53
911.86:025:53
1011.96:015:53
1111.96:015:53
1211.96:005:53
1311.95:595:53
1411.95:585:53
1511.95:585:53
1611.95:575:53
1711.95:565:53
1812.05:565:53
1912.05:555:53
2012.05:545:53
2112.05:535:53
2212.05:535:53
2312.05:525:53
2412.05:515:53
2512.05:505:53
2612.15:505:53
2712.15:495:53
2812.15:485:53
2912.15:485:53
3012.15:475:53

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.66 kWh/m².

For context, solar energy here swings from a low near 4.53 kWh/m² to a high of 5.73 kWh/m² in October across the year — September's 5.66 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
15.5Bright
25.5Bright
35.5Bright
45.5Bright
55.6Bright
65.6Bright
75.6Bright
85.6Bright
95.6Bright
105.6Bright
115.6Bright
125.6Bright
135.7Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.7Bright
195.7Bright
205.7Bright
215.7Bright
225.7Bright
235.7Bright
245.7Bright
255.8Bright
265.8Bright
275.8Bright
285.8Bright
295.8Bright
305.8Bright
Planning a trip in September

Hazard calendar for Vilhena

In seasonPeak

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

Vilhena's monsoon runs October–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 Vilhena?

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

4.0
Sightseeing
5th-best month of the year
6.1
Beach & pool
5th-best month of the year

September is a reasonable time to visit Vilhena for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Vilhena in September

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

In September, Vilhena sees daytime highs around 31°C and nights near 21°C. Pack light clothes. Worth having: rain gear and sun protection. About 14 days see rain.

light clothesrain gearsun protection

UV index in Vilhena in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 3 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Vilhena peaks around January 22 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near September 15 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateExtremeJan 22UV 15Sep 15UV 4
UV index (midday)Level
Jan15Extreme
Feb15Extreme
Mar14Extreme
Apr13Extreme
May10Very high
Jun9Very high
Jul8Very high
Aug10Very high
Sep3Moderate
Oct12Extreme
Nov13Extreme
Dec14Extreme

Air quality in Vilhena 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 Vilhena is worst in September — around 62 µg/m³ PM2.5 (unhealthy), about 7.2× the cleanest month (May, 9 µg/m³).

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

020406080JanFebMarAprMayJunJulAugSepOctNovDecGoodModeratePoorModerateSep 1459 µg/m³May 159 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb10Good
Mar10Good
Apr9Good
May9Good
Jun9Good
Jul11Good
Aug39Poor
Sep62Unhealthy
Oct22Moderate
Nov16Moderate
Dec11Good
Location & terrain

Where is Vilhena?

Vilhena sits at 12.7°S, 60.1°W, 591 m above sea level, in Brazil. The nearest listed city is Colorado do Oeste, 60 km away.

Topography around Vilhena

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

Within 3 km, the terrain around Vilhena has only modest variations in elevation — a maximum elevation change of 75 m around an average of 585 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 226 m; within 80 km, significant variations in elevation — a maximum elevation change of 438 m.

The land around Vilhena is covered by artificial surfaces (47%) and grassland (26%) within 3 km, trees (50%), cropland (24%) and grassland (20%) within 16 km, and trees (76%) within 80 km.

3 km
75 m
16 km
226 m
80 km
438 m
treesshrubsgrasslandcroplandartificial surfacesbare terrain
September weather nearby: Colorado do Oeste 60 km · Cerejeiras 88 km · Comodoro 110 km · Pimenta Bueno 165 km · Espigão dOeste 165 km · Sapezal 169 km · Cacoal 202 km · Rolim de Moura 208 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 Vilhena (-12.7406°, -60.1458°, elevation 591 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).