Weather in Brno in September 2025
Average weather
Average temperature in Brno in September
The temperature in September is +77°F on average, with a range between a maximum of +84°F during the day and a minimum of +50°F at night.
The average maximum temperature goes up 0% by the end of the month, compared with the beginning of the month, from +72°F to +72°F.
Is Brno warm or cold in September?
Brno is typically mild in September.
Maximum temperatures go down compared to the previous month from +77°F to +68°F. The minimum temperature also goes down from +59°F to +52°F.
Pack a light jacket as it will be warm in the day and cool in the evenings.
Take a look at how September is compared to other months in Brno:
Climate in Brno in September
| August | September | October | ||||
|---|---|---|---|---|---|---|
| Avg. temperature | ||||||
| +77°F | +68°F | +57°F | ||||
| Min. temperature | ||||||
| +39°F | +34°F | +23°F | ||||
| Max. temperature | ||||||
| +97°F | +90°F | +81°F | ||||
| Rainfall | ||||||
| 78 mm | 60 mm | 41 mm | ||||
| Wind | ||||||
| 2 m/s | 2 m/s | 2 m/s | ||||
| Humidity | ||||||
| 70% | 76% | 82% | ||||
| Air pressure | ||||||
| 1015 HPa | 1016 HPa | 1018 HPa | ||||
| Sunny days | ||||||
| 9 | 8 | 6 | ||||
| Cloudy days | ||||||
| 4 | 8 | 12 | ||||
| Rainy days | ||||||
| 16 | 14 | 13 | ||||
| Snowy days | ||||||
| 0 | 0 | 0 | ||||
September typically has worse weather conditions compared to August. It’s getting colder in September. From +77°F in the day, the average maximum temperature lowers to +68°F. As September arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 78 mm to 60 mm. Humidity rises from 70% to 76%. The average wind speed doesn’t change much during September, staying around 2 m/s. The days becoming less sunny, going from 9 sunny days in August to 8 in September.
October brings much the same weather, it remains ok.
Wind
The average wind speed is 3 m/s getting up to 6 m/s which is a medium breeze. You can feel it, especially getting out of the water.
The average wind speed in Brno is gradually increasing during September, going from 1 m/s to 3 m/s over the course of the month.
Rain
How was the weather last September in Brno?
Climate Change Over the Years
The climate in Brno in September has not changed that much over the last 43 years.
The average temperature was the lowest in 1996 (+53°F) and the highest in 2023 (+61°F). The driest year was 1983 with only 359 mm of rainfall, and the wettest year was 2021 with 1029 mm.
FAQ
Is September a good time to visit Brno?
Can you sunbathe in Brno in September?
Is Brno rainy in September?
Is it sunny in Brno in September?
Other cities in Czech Republic
Monthly weather in Brno
Source of the data
For this page, we’ve looked at the typical weather in Brno, based on historical hourly weather data from January 1, 1979, to December 31, 2023.
For past dates, we show actual recorded data at the location at that time. Forecasts are based on recorded weather during that day of the year, averaged over the total years for which we have records (unless stated otherwise). The daily temperature is the highest recorded temperature in the shadow during that day.