If you plan to visit Basel in September, the weather is typically alright, with an average high temperature of +70°F during the day and approximately 8 sunny days. Expect some rainy, though, as there are typically 10 rainy days in the month and around 87 mm of precipitation. The weather is changeable so you may have to pack for every eventuality. Search flightsin one click on Avionero.
Average weather
☀️
+70°F
Avg. max. temperature
+36°F
Min.
+90°F
Max.
87 mm
Total precipitation
77%
Avg. humidity
1 m/s
Avg. wind
8 ☀️
Sunny Days
12 ⛅️
Cloudy
10 🌦
Rainy
Our opinion: Basel has OK weather in September.
Average temperature in Basel in September
Here are the expected maximum, average and minimum temperatures in Basel for September based on the historical data.
Last Year
Historical Data
The expected average maximum temperature in September is +70°F with a maximum of +84°F and a minimum of +41°F.
The average maximum temperature goes down 42% by the end of the month, compared with the beginning of the month, from +77°F to +59°F.
Is Basel warm or cold in September?
Basel is typically mild in September.
Maximum temperatures go down compared to the previous month from +77°F to +70°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 Basel:
Climate in Basel in September
Basel weather looks like this, on average, in September and the surrounding months.
August
September
October
Avg. temperature
+77°F
+70°F
+61°F
Min. temperature
+43°F
+36°F
+25°F
Max. temperature
+102°F
+90°F
+86°F
Rainfall
119 mm
87 mm
87 mm
Wind
1 m/s
1 m/s
1 m/s
Humidity
72%
77%
82%
Air pressure
1015 HPa
1016 HPa
1016 HPa
Sunny days
10
8
4
Cloudy days
10
12
17
Rainy days
11
10
10
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 +70°F.As September arrives, the amount of rainfall goes down. On average, the rainfall volume decreases from 119 mm to 87 mm.Humidity rises from 72% to 77%.The average wind speed doesn’t change much during September, staying around 1 m/s.The days becoming less sunny, going from 10 sunny days in August to 8 in September.
October brings much the same weather, it remains ok.
Wind speed in Basel in September based on historical data.
Last Year
Historical Data
The average wind speed is 2 m/s getting up to 5 m/s which is a light breeze; barely moving the tree leaves.
The average wind speed in Basel is gradually decreasing during September, going from 2 m/s to 1 m/s over the course of the month.
Rain
Amount of rainfall in mm during September in Basel based on historical data.
Last Year
Historical Data
Total precipitation in September is about 163 mm, with a 70% chance of rain on a typical day. The maximum amount of rainfall per day is around 22 mm, which is considered light rain.September is a pretty wet month with over 21 rainy days, so don’t forget to pack an umbrella, raincoat, and a pair of wellies.
Here’s how September is compared with other months in the amount of precipitation, total mm:
Basel wettest month is May, where a typical day has a 45% chance of precipitation and 129 mm of rainfall per day. February, on the other hand, is the driest month with a mere 24% chance of precipitation and 60 mm of rainfall per day.
How was the weather last September in Basel?
This is the weather in Basel in September 2023:
1 September
☀️
+76°F
2 September
☀️
+79°F
3 September
🌧️
+77°F
4 September
☀️
+82°F
5 September
☀️
+84°F
6 September
☀️
+76°F
7 September
☀️
+78°F
8 September
🌧️
+74°F
9 September
🌧️
+72°F
10 September
🌧️
+68°F
11 September
☀️
+74°F
12 September
☀️
+78°F
13 September
☀️
+83°F
14 September
🌧️
+77°F
15 September
🌧️
+69°F
16 September
🌧️
+64°F
17 September
🌧️
+59°F
18 September
☀️
+64°F
19 September
☀️
+63°F
20 September
☀️
+64°F
21 September
☀️
+65°F
22 September
☀️
+67°F
23 September
☀️
+70°F
24 September
🌧️
+60°F
25 September
☁️
+62°F
26 September
☁️
+62°F
27 September
🌧️
+55°F
28 September
🌧️
+53°F
29 September
🌧️
+55°F
30 September
☁️
+59°F
In September 2023 Basel had 15 sunny days, 3 cloudy days, and 12 rainy days. The average maximum temperature was +70°F, with an absolute maximum of +84°F and a minimum of +54°F. The average humidity was 78%, with a maximum of 100% and a minimum of 41%. The average wind speed was 2 m/s, with a maximum of 7 m/s and a minimum of 0 m/s.
Are you planning a trip in September?
Climate Change Over the Years
This is how Basel climate has changed over the last 43 years.
The climate in Basel in September has not changed that much over the last 43 years.
The average temperature was the lowest in 2001 (+65°F) and the highest in 2016 (+79°F). The driest year was 1996 with only 42 mm of rainfall, and the wettest year was 1984 with 175 mm.
FAQ
Frequently asked questions about the weather in Basel in September:
Is September a good time to visit Basel?
It’s always a good time to visit Basel, but the weather is changeable in September, so plan a mix of indoor and outdoor activities and exploring, and pack for every eventuality.
Can you sunbathe in Basel in September?
September has mild temperatures in Basel. Not ideal for sunbathing, but still good for daytime outdoor activities, but plan for cool evenings. Pack a light jacket and shorts!
Is Basel rainy in September?
Basel is often rainy in September. You may get a bit damp when outside, so pack an umbrella, and maybe even a raincoat.
Is it sunny in Basel in September?
Usually, it’s not very sunny in Basel in September, often it’s pretty cloudy. Pack for any eventuality; layering can help reduce the number of bulky items needed.
Other cities in Switzerland
Check out the weather for other cities in Switzerland.
For this page, we’ve looked at the typical weather in Basel, based on historical hourly weather data from January 1, 1979, to December 31, 2022.
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.