Temperatures in September
It's cold in September in Longyearbyen with an average temperature of 5°C. Temperatures this month range from a low of 3°C to a high of 7°C. At night, you can expect temperatures between -1°C and 3°C.
Max and Min Temperatures per Day
This chart shows the daily maximum and minimum temperatures in degrees Celsius for Longyearbyen 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 Longyearbyen with cold temperatures, averaging around 6°C during the day and nights close to 3°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 5°C, with nights close to 1°C. There might be a few showers during this period, but plenty of dry days with sunshine too. Wear a thick winter coat, jumper, long trousers, hat, and gloves.
End of September
By the end of September, the average daytime temperature in Longyearbyen will be around 4°C, with nights close to 1°C. A shower might show up, but overall the weather will be dry and sunny. Wear a thick winter coat, jumper, long trousers, hat, and gloves.
Precipitation in September
In September, there is an average of 91 mm of precipitation, spread over 14 days. Of the total precipitation, about 14 cm falls as snow in September. The wind speed is around 5 Bft, mostly coming from the South.
The average precipitation chance is 48% per day this month.
Precipitation Chance
This chart shows the daily precipitation chance (in percentages) in September for Longyearbyen. 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.
Longyearbyen in September |
London | ||
|---|---|---|---|
 Average Temperature |
5°C | 20°C | |
 High Temp |
7°C | 22°C | |
| Low Temp |
3°C | 17°C | |
 Total Precipitation |
91 mm | 44 mm | |
| Rainy Days |
14 days | 8 days | |
 Total Snowfall |
14 cm | 0 cm | |
| Snowy Days |
6 days | 0 days | |
August
UV index
The UV index is a maximum of 2 this month. That's a low value on the intensity scale of 1 to 11. The risk of sunburn is minimal at this time.
Temperature records for Longyearbyen in September
With 13°C, Longyearbyen hit the highest temperature in the last 10 years in September 2017. The lowest daytime temperature in this month was -7°C in 2023. The extreme night temperatures ranged from a low of -9°C to a high of 9°C.
Check out the climate of Longyearbyen for all months and discover the best travel time
Daily Temperature in September in Longyearbyen
This chart shows the average daily temperatures, both day and night, for each day in September in Longyearbyen, 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 Longyearbyen
The chart below shows the average daily precipitation in September for Longyearbyen, 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 14 days of rain in Longyearbyen.
Daily Snowfall in September in Longyearbyen
This chart shows the average daily snowfall in September in Longyearbyen, measured in centimetres. The bottom of the chart shows the days of the month. The data is based on historical measurements and gives an idea of the average snowfall in September.
Daily UV Index in September in Longyearbyen
This chart shows the average daily UV index in September in Longyearbyen, 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 Longyearbyen Over the Years
This chart shows the average temperature in September in Longyearbyen, measured in degrees Celsius, over the past years.
Total Precipitation in September in Longyearbyen Over the Years
This chart shows the average precipitation in September in Longyearbyen, measured in millimetres over the past years. Precipitation is always measured as water, even if it’s snow or hail.
Snowfall in September in Longyearbyen per year
This chart shows the average snowfall in September in Longyearbyen, measured in centimetres, over the past years.
Daily climate in September for Longyearbyen
Click on a specific day in September for detailed info on the typical weather on that day in Longyearbyen. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Longyearbyen
Have you been to Longyearbyen in September?
Share your weather experience in September in Longyearbyen.
Average Weather in Longyearbyen by Month
Click on a month below to see detailed weather info for Longyearbyen. 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 Longyearbyen for all months at once
