Rondônia Weather in September

Average temperatures, rainfall, sunshine and the best places to visit in Rondônia, Brazil in September.

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Porto Velho Ariquemes Ji-Paraná Vilhena

Considering a trip to Rondônia, Brazil this September and wondering about the expected weather conditions? Find all the crucial information you need right here, addressing your question:

What to Expect in Rondônia in September

Rondônia, Brazil is a region in Brazil. September in Rondônia generally has very warm temperatures, with precipitation levels ranging from moderate to high.

Temperatures

The average maximum temperatures are very warm and range from 33°C (91°F) in Vilhena to 35°C (95°F) in Ariquemes. Nighttime temperatures generally drop to 23°C (73°F) in Ariquemes and 21°C (70°F) in Vilhena. The temperatures cited for both day and night represent usual averages, but it's possible some days could be hotter. It's advisable to dress accordingly to handle the heat.

For specific regional insights in Rondônia, Brazil, refer to the map provided below.

Precipitation

In September, precipitation varies across different areas. From moderate rainfall in Ji-Paraná with an average of 87 mm (3.4 in) to high rainfall in Porto Velho with 105 mm (4.1 in).

Explore Rondônia by month

Pick a month to see the average temperature, rainfall and sunshine in Rondônia — and find the best time to visit. (based on Porto Velho)

January31°C (88°F) February31°C (88°F) March31°C (88°F) April31°C (88°F) May31°C (88°F) This monthJune32°C (90°F) July33°C (91°F) August35°C (95°F) September34°C (93°F) October33°C (91°F) November32°C (90°F) December31°C (88°F)
Best Time to Visit Rondônia →

Best Places to Visit in Rondônia in September

Click on a destination dot for more details. Toggle the map to compare temperatures or precipitation across Rondônia.

Conditions Temperatures Precipitation
perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

Popular Destinations in Rondônia

What is the weather like in September for some of the most popular destinations in Rondônia, Brazil?

Temperature range in Rondônia (September)

Precipitation variation in Rondônia (September)

Porto Velho

In September Porto Velho generally has very high temperatures with maximum daytime temperatures around 34°C (93°F), minimum nighttime temperatures around 24°C (75°F) and high monthly rainfall. So on average the conditions are unpleasant that month.

« August
September
October »
August
September
October
Max temperature
35°C (95°F)
34°C (93°F)
33°C (91°F)
Min temperature
23°C (73°F)
24°C (75°F)
24°C (75°F)
Monthly rainfall
44 mm (1.7 in)
105 mm (4.1 in)
174 mm (6.9 in)
Monthly rainy days
6 days
9 days
14 days
Weather conditions
unpleasant
unpleasant
tolerable
Climate in Porto Velho →

Ariquemes

In September Ariquemes generally has very high temperatures with maximum daytime temperatures around 35°C (95°F), minimum nighttime temperatures around 23°C (73°F) and moderate monthly rainfall. So on average the conditions are unpleasant that month.

« August
September
October »
August
September
October
Max temperature
36°C (97°F)
35°C (95°F)
34°C (93°F)
Min temperature
22°C (72°F)
23°C (73°F)
23°C (73°F)
Monthly rainfall
35 mm (1.4 in)
93 mm (3.7 in)
149 mm (5.9 in)
Monthly rainy days
5 days
8 days
12 days
Weather conditions
poor
unpleasant
unpleasant
Climate in Ariquemes →

Ji-Paraná

In September Ji-Paraná generally has very high temperatures with maximum daytime temperatures around 35°C (95°F), minimum nighttime temperatures around 23°C (73°F) and moderate monthly rainfall. So on average the conditions are unpleasant that month.

« August
September
October »
August
September
October
Max temperature
35°C (95°F)
35°C (95°F)
34°C (93°F)
Min temperature
22°C (72°F)
23°C (73°F)
23°C (73°F)
Monthly rainfall
24 mm (0.9 in)
87 mm (3.4 in)
144 mm (5.7 in)
Monthly rainy days
4 days
7 days
11 days
Weather conditions
tolerable
unpleasant
unpleasant
Climate in Ji-Paraná →

Vilhena

In September Vilhena generally has very high temperatures with maximum daytime temperatures around 33°C (91°F), minimum nighttime temperatures around 21°C (70°F) and moderate monthly rainfall. So on average the conditions are pleasant that month.

« August
September
October »
August
September
October
Max temperature
33°C (91°F)
33°C (91°F)
31°C (88°F)
Min temperature
20°C (68°F)
21°C (70°F)
21°C (70°F)
Monthly rainfall
24 mm (0.9 in)
89 mm (3.5 in)
172 mm (6.8 in)
Monthly rainy days
3 days
6 days
10 days
Weather conditions
perfect
pleasant
tolerable
Climate in Vilhena →

Cacoal

In September Cacoal generally has very high temperatures with maximum daytime temperatures around 34°C (93°F), minimum nighttime temperatures around 23°C (73°F) and moderate monthly rainfall. So on average the conditions are tolerable that month.

« August
September
October »
August
September
October
Max temperature
35°C (95°F)
34°C (93°F)
33°C (91°F)
Min temperature
21°C (70°F)
23°C (73°F)
23°C (73°F)
Monthly rainfall
26 mm (1 in)
90 mm (3.5 in)
153 mm (6 in)
Monthly rainy days
3 days
6 days
11 days
Weather conditions
tolerable
tolerable
tolerable
Climate in Cacoal →

Is your destination not in the list? Have a look at all destinations in Rondônia, in Brazil.

Popular cities in September

Day & night temperatures, rainfall and average weather in Rondônia in September.

City Weather Day temp Night temp Rainfall
Porto Velho 34°C (93°F) 24°C (75°F) 105 mm (4.1 in)
Ariquemes 35°C (95°F) 23°C (73°F) 93 mm (3.7 in)
Ji-Paraná 35°C (95°F) 23°C (73°F) 87 mm (3.4 in)
Vilhena 33°C (91°F) 21°C (70°F) 89 mm (3.5 in)
Cacoal 34°C (93°F) 23°C (73°F) 90 mm (3.5 in)
Rondônia 35°C (95°F) 23°C (73°F) 88 mm (3.5 in)

Rondônia weather in September: frequently asked questions

What is the weather like in Rondônia, Brazil in September?

In September, Rondônia, Brazil generally has poor weather conditions. Porto Velho sees daytime temperatures near 34°C (93°F), with nights cooling to roughly 24°C (75°F).

What is the average temperature in Rondônia, Brazil in September?

In Porto Velho, the average daytime high in September is 34°C (93°F), while nighttime temperatures drop to around 24°C (75°F).

Does Rondônia, Brazil get a lot of rain in September?

Porto Velho typically receives notable rainfall in September, about 105 mm (4.1 in) on average across Rondônia, Brazil.

Is September a Good Time to Visit Rondônia, Brazil?

In our view, September might not be the best time to travel to Rondônia, Brazil with often unpleasant weather in Porto Velho.

On average, the best time to visit Rondônia, Brazil is in June and July with generally tolerable weather in Porto Velho. On the other hand, the weather in January, February, March, April, August, September, October, November and December tend to be poor.

Interested in more climate information?

We have much more information about the climate in Rondônia.

Weather and climate has detailed information for every country in the world. Are you going to Brazil? Get detailed historical weather averages for many cities in Brazil.

Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal travel conditions. Find out where to go with our weather planner.

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