September weather forecastHarstad, Norway
September
Weather in September
September brings the beginning of autumn to Harstad, with a further dip in average temperature to 10.9°C (51.6°F). The autumn equinox ensures a balanced distribution of day and night, accounting for equal periods of sunlight and darkness. Autumn paints the city with a palette of bright orange and yellow, contributing to the city's aesthetic appeal. With the progression into October, the weather in Harstad becomes noticeably colder, and the city discovers a new rhythm under the increasingly shorter days.Temperature
Harstad's transition from August to September introduces an average high-temperature of a fresh 10.9°C (51.6°F), marking an insignificant variation from the 13.8°C (56.8°F). Harstad's nighttime temperature in September experiences a slight dip from daytime highs, falling to an average of 7.9°C (46.2°F).Humidity
In Harstad, the average relative humidity in September is 79%.Rainfall
In Harstad, during September, the rain falls for 17.5 days and regularly aggregates up to 65mm (2.56") of precipitation. In Harstad, during the entire year, the rain falls for 154.2 days and collects up to 862mm (33.94") of precipitation.Snowfall
Months with snowfall in Harstad are January through June, September through December. September is the first month it typically snows. Throughout September, in the average 0.4 snowfall days, it receives 3mm (0.12") of snow. Throughout the year, there are 94.6 snowfall days, and 1922mm (75.67") of snow is accumulated.Sea temperature
In September, the average sea temperature is 10.7°C (51.3°F).Note: Swimming in 10.7°C (51.3°F) feels unbearing at 13°C (55.4°F) and can be life-risking below 10°C (50°F), causing breathing issues and cold shock, depending on a person's capacity.
Daylight
In Harstad, the average length of the day in September is 13h and 16min.On the first day of the month, sunrise is at 05:18 and sunset at 20:28. On the last day of September, sunrise is at 07:06 and sunset at 18:21 CEST.
Sunshine
In September, the average sunshine in Harstad is 6.5h.UV index
The average daily maximum UV index in September in Harstad is 2. A UV Index value of 2, and less, symbolizes a minimal health vulnerability from unsafe exposure to UV radiation for the average person.Note: The maximum daily UV index, 2 in September, converts into the following recommendations:
Babies, children, and individuals with sensitive skin should always have protection against extended sun exposure. Direct exposure to the Sun during its peak hours around mid-day should be minimized for safety. Stay sun-safe with clothing that is both closely woven and worn loosely. Foresee this! The reflection from snow can nearly double the intensity of UV radiation from the Sun.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Harstad, Norway
- Average high temperature in September: 10.9°C
The warmest month (with the highest average high temperature) is July (14.1°C).
The month with the lowest average high temperature is February (-1.2°C).
- Average low temperature in September: 7.9°C
The months with the highest average low temperature are July and August (9.9°C).
The coldest month (with the lowest average low temperature) is February (-4.5°C).
Average pressure in September
Harstad, Norway
- Average pressure in September: 1008.9mbar
The month with the highest atmospheric pressure is May (1013.9mbar).
The month with the lowest atmospheric pressure is December (1000.9mbar).
Average wind speed in September
Harstad, Norway
- Average wind speed in September: 13.7km/h
The windiest month (with the highest average wind speed) is March (19.3km/h).
The calmest month (with the lowest average wind speed) is July (11.1km/h).
Average humidity in September
Harstad, Norway
- Average humidity in September: 79%
The month with the highest relative humidity is April (83%).
The months with the lowest relative humidity are October, November and December (77%).
Average rainfall in September
Harstad, Norway
- Average rainfall in September: 65mm
The wettest month (with the highest rainfall) is March (95mm).
The driest months (with the least rainfall) are May and July (53mm).
Average rainfall days in September
Harstad, Norway
- Average rainfall days in September: 17.5 days
The month with the highest number of rainy days is September (17.5 days).
The month with the least rainy days is February (6.3 days).
Average snowfall in September
Harstad, Norway
- Average snowfall in September: 3mm
The month with the highest snowfall is March (417mm).
The months with the least snowfall are July and August (0mm).
Average snowfall days in September
Harstad, Norway
- Average snowfall days in September: 0.4 days
The month with the highest number of snowfall days is March (19.2 days).
The months with the least snowfall days are July and August (0 days).
Average sea temperature in September
Harstad, Norway
- Average sea temperature in September: 10.7°C
The best month for swimming (with the highest average sea temperature) is August (12.3°C).
The coldest month (with the lowest average sea temperature) is March (3.8°C).
Average daylight in September /
Average sunshine in September
Harstad, Norway
- Average daylight in September: 13h and 18min
The month with the longest days is August (Average daylight: 17h and 42min).
The month with the shortest days is June (Average daylight: 0h and 0min).
- Average sunshine in September: 6h and 30min
The month with the most sunshine is August (Average sunshine: 9h and 0min).
The month with the least sunshine is December (Average sunshine: 0h and 18min).
Average sunshine days in September
Harstad, Norway
- Average sunshine days in September: 11.2 days
The month with the most sunshine days is January (13.6 days).
The month with the least sunshine days is March (8.3 days).
Average UV index in September
Harstad, Norway
- Average UV index in September: 2
The month with the highest UV index is July (UV index 4).
The months with the lowest UV index are February, March and November (UV index 1).
Average cloud cover in September
Harstad, Norway
- Average cloud cover in September: 57
The month with the most cloud cover is March (Cloud cover 67).
The month with the least cloud cover is August (Cloud cover 52).
Average visibility in September
Harstad, Norway
- Average visibility in September: 9km
The months with the highest visibility are January, February, May, June, July, August, September, October, November and December (9km).
The months with the lowest visibility are March and April (8km).





