Temperatures in September
It's pleasantly warm in September in Cardiff with an average temperature of 19°C. Temperatures this month range from a low of 16°C to a high of 20°C. At night, you can expect temperatures between 10°C and 14°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Cardiff 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 Cardiff with mild temperatures, averaging around 20°C during the day and nights close to 13°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 19°C, with nights close to 12°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 Cardiff will be around 18°C, with nights close to 11°C. There’s regular precipitation, but with a bit of luck, you’ll also get some dry and sunny days.
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Precipitation in September
In September, there is an average of 92 mm of precipitation, spread over 13 days. The wind speed is around 4 Bft, mostly coming from the Southwest.
The average precipitation chance is 43% per day this month. The weather’s variable. There are also a few days with higher precipitation chances.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Cardiff. 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.
Cardiff in September |
London | ||
|---|---|---|---|
 Average Temperature |
19°C | 20°C | |
 High Temp |
20°C | 22°C | |
| Low Temp |
16°C | 17°C | |
 Total Precipitation |
92 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 Cardiff?
Want nice weather? Then September is a great time to be in Cardiff. You’ll have pleasant temperatures and not too much rain this month.
Temperature records for Cardiff in September
With 28°C, Cardiff hit the highest temperature in the last 10 years in September 2021. The lowest daytime temperature in this month was 10°C in 2018. The extreme night temperatures ranged from a low of 0°C to a high of 21°C.
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Daily Temperature in September in Cardiff
This chart shows the average daily temperatures, both day and night, for each day in September in Cardiff, 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 Cardiff
The chart below shows the average daily precipitation in September for Cardiff, 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 Cardiff.
Daily UV Index in September in Cardiff
This chart shows the average daily UV index in September in Cardiff, 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 Cardiff Over the Years
This chart shows the average temperature in September in Cardiff, measured in degrees Celsius, over the past years.
Total Precipitation in September in Cardiff Over the Years
This chart shows the average precipitation in September in Cardiff, 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 Cardiff
Click on a specific day in September for detailed info on the typical weather on that day in Cardiff. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Cardiff
Have you been to Cardiff in September?
Share your weather experience in September in Cardiff.
Average Weather in Cardiff by Month
Click on a month below to see detailed weather info for Cardiff. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
