Temperatures in September
It's cool to moderate in September in Trondheim with an average temperature of 15°C. Temperatures this month range from a low of 13°C to a high of 17°C. At night, you can expect temperatures between 7°C and 11°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Trondheim in September. The red line indicates the max temperatures, and the blue line shows the minimums.
Start of September
The month of September starts in Trondheim with cool temperatures, averaging around 17°C during the day and nights close to 10°C. A few showers might pop up in the first days of the month, but the weather remains mostly sunny and dry.
Mid-September
By mid-September, the average daytime temperature drops to around 15°C, with nights close to 9°C. There might be a few showers during this period, but plenty of dry days with sunshine too.
End of September
By the end of September, the average daytime temperature in Trondheim will be around 15°C, with nights close to 9°C. A shower might show up, but overall the weather will be dry and sunny.
Discover cheap trips to Trondheim 
Water temperature
The water temperature at Trondheim is 16°C this month. This is probably too cold to swim without protective gear.
Precipitation in September
In September, there is an average of 80 mm of precipitation, spread over 13 days. The wind speed is around 4 Bft, mostly coming from the South.
The average precipitation chance is 42% per day this month. The weather’s variable. Some days have higher and others lower precipitation chances, which lowers the average.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Trondheim. 0% means it never rained on that day in the past 10 years, and 100% means it rained every day. All values in between represent the average chance of precipitation on that day.
Trondheim in September |
London | ||
|---|---|---|---|
 Average Temperature |
15°C | 20°C | |
 High Temp |
17°C | 22°C | |
| Low Temp |
13°C | 17°C | |
 Total Precipitation |
80 mm | 44 mm | |
| Rainy Days |
13 days | 8 days | |
August
UV index
The UV index is a maximum of 5 this month. That's a moderate value on the intensity scale of 1 to 11. Unprotected skin can burn in about 30 minutes.
Is September a good time to visit Trondheim?
Looking for sun and warm weather? Then September isn’t the best time to be in Trondheim. The temperature is too low this month for a warm stay.
Temperature records for Trondheim in September
With 24°C, Trondheim hit the highest temperature in the last 10 years in September 2023. The lowest daytime temperature in this month was 6°C in 2019. The extreme night temperatures ranged from a low of 1°C to a high of 15°C.
Check out the climate of Trondheim for all months and discover the best travel time
Curious about the climate in other parts of Norway? Check out the weather and climate in places like Oslo, Lofoten, Vesterålen, or have a look at other destinations in Norway.
Plan your next holiday
Don’t miss the best holiday deals for Trondheim and see what our partners have for you.
Daily Temperature in September in Trondheim
This chart shows the average daily temperatures, both day and night, for each day in September in Trondheim, measured in degrees Celsius. The red line represents the maximum temperatures, while the blue line shows the minimums. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, gives an overview of the average daily temperatures during this month.
Daily Precipitation in September in Trondheim
The chart below shows the average daily precipitation in September for Trondheim, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are shown at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that rain is more likely. But it’s still an average, so each day can be different. Based on historical weather data for September, you can expect around 13 days of rain in Trondheim.
Daily UV Index in September in Trondheim
This chart shows the average daily UV index in September in Trondheim, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Trondheim Over the Years
This chart shows the average temperature in September in Trondheim, measured in degrees Celsius, over the past years.
Total Precipitation in September in Trondheim Over the Years
This chart shows the average precipitation in September in Trondheim, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Daily climate in September for Trondheim
Click on a specific day in September for detailed info on the typical weather on that day in Trondheim. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Trondheim
Have you been to Trondheim in September?
Share your weather experience in September in Trondheim.
Average Weather in Trondheim by Month
Click on a month below to see detailed weather info for Trondheim. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Trondheim for all months at once
