September Weather in Harstad, Norway

Last updated: August 27, 2025

In Harstad, Norway, September brings a refreshing mix of weather patterns, with temperatures ranging from a comfortable 21°C (70°F) at their peak to a chilly -1°C (31°F) at night. The average temperature hovers around 9°C (48°F), inviting residents and visitors alike to embrace the transition into autumn. This month is characterized by 130 mm (5.1 in) of precipitation spread across 17 days, contributing to the lush scenery of the region. With an average humidity of 88%, the air feels crisp and invigorating, making September a perfect time to explore the stunning natural beauty that Harstad has to offer.

September Temperature in Harstad

September in Harstad, Norway, ushers in a noticeable shift in temperatures as the warmth of summer begins to wane. With minimums dipping to -1°C (31°F) and averages hovering around 9°C (48°F), the month marks a transition from the balmy days of August. Despite the slight cooling, the maximum temperature can still reach a satisfying 21°C (70°F), offering a pleasant reprieve before the colder months. This blend of crisp air and lingering warmth creates a vibrant atmosphere, allowing locals and visitors alike to enjoy the beautiful landscapes adorned in early autumn hues. As the days grow shorter, the cool evenings invite cozy gatherings, making September a charming month in this enchanting Arctic locale.

September Weather in Harstad: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Harstad, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Harstad, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec242227334250555448393226
Data source: Temperature data for Harstad generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Harstad

In September, Harstad experiences a noteworthy shift in its precipitation patterns, receiving 130 mm (5.1 in) of rainfall over 17 days. This marks a slight increase from August's 127 mm (5.0 in), continuing the trend of a wet late summer as temperatures begin to cool. The consistent rainfall, characteristic of the transition toward autumn, showcases the region's varied climate, where wet days are prevalent. As September unfolds, the increase in rain often enhances the lush, vibrant landscapes of Northern Norway, setting the stage for the stunning fall scenery that follows. This gradual uptick in precipitation not only reflects the approach of winter but also highlights the dynamic weather fluctuations typical for this time of year.

September Precipitation Trends in Harstad

The chart displays monthly precipitation patterns in Harstad, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Harstad, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec981071361008511710112713010310997
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Harstad

In September, Harstad, Norway experiences a notable shift in humidity levels, rising to 88%. This figure aligns closely with the wetter months at both ends of the year, January and October, which also hold humidity measurements of 89% and 88%, respectively. After a gradual decline during the milder spring and early summer months—peaking at 77% in May—humidity begins to creep back up, hinting at the approaching autumnal chill. The overall trend shows that Harstad maintains a fairly high humidity throughout most of the year, with only a slight dip during the warmer months. As the air grows thicker in September, residents can expect a return to the familiar moist air that characterizes much of Norway's climate.

September Average Humidity in Harstad

This chart illustrates the average monthly humidity levels in Harstad, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Harstad is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec89%88%85%83%77%82%83%84%88%88%87%87%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Harstad

As September rolls into Harstad, the UV Index reflects a gentle decline from the vibrant summer months, settling at 3, which categorizes it as moderate. With a recommended burn time of just 30 minutes, it’s an ideal time to enjoy outdoor activities while still being mindful of sun exposure. This shift is part of a noticeable annual trend, where the UV Index gradually decreases from its summer peak, providing a safe environment for residents and visitors alike. As the season transitions, it’s wise to keep sun safety in mind, ensuring that you don’t miss out on the stunning autumnal landscapes. For more detailed insights on UV levels throughout the year, check out the Harstad UV Index.

Maximum UV Index Levels in Harstad for September

The chart shows the monthly maximum UV Index (UVI) for Harstad in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Harstad typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec112345543110
Data source: Harstad September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Harstad

September in Harstad, Norway, greets residents with a delightful 290 hours of sunshine, a gentle farewell to the vibrant summer days. As the days grow shorter, this month marks a notable decline from July's peak of 473 hours, yet it remains a bright beacon compared to the winter months ahead. The transition into autumn is evident as the sun’s warmth lingers, but as October approaches, the light diminishes significantly, dipping to just 181 hours. This trend highlights a fascinating pattern in Harstad's climate: a gradual buildup of sunshine from the bleak winter months, peaking in mid-summer before gracefully tapering off. September, therefore, stands out as a splendid bridge between the lingering warmth of summer and the cool embrace of autumn, inviting both locals and visitors to relish the beauty of a waning season.

Monthly Sunshine Duration in Harstad: September Highlighted

The September sunshine duration represents the total number of hours Harstad experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec16h112h241h340h455h462h473h383h290h181h32h0h
Data source: Harstad September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Harstad During September

In Harstad, Norway, the chance of sunny weather in September hovers around 20%, marking it as a transitional month as summer wanes. This figure is slightly above the gray and gloomy days of October, which drops to 13%, but significantly lower than the sunnier months of January and December, both at 34%. Notably, September also falls within a general trend of decreasing sunshine probabilities; after peaking in April at 27%, the likelihood of clear skies declines consistently through the summer. As autumn sets in, potential sunny days become rarer, inviting cozy indoor activities as the breathtaking natural landscapes prepare for winter's embrace.

Percentage of Sunny Days in September in Harstad

The chart illustrates the percentage of sunny days in Harstad throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Harstad experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec35%19%19%27%24%25%22%16%20%13%18%34%
Data source: Harstad September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Harstad in September

In Harstad, Norway, the transition into September marks a significant shift in daylight duration as summer gives way to autumn. After enjoying a remarkable 24 hours of daylight in June, the month of September welcomes just 13 hours of sunshine, indicating a gradual decline as the days shorten. This pattern reflects a wider trend where daylight peaks in the summer months and then steadily decreases, with November offering a mere 7 hours and December plunging into complete darkness. The month's diminishing light signals the end of the vibrant summer season, making way for the cozy ambiance of autumn in this picturesque northern town.

Average Daylight Hours in Harstad for September

The chart illustrates the variation in daylight duration in Harstad throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec5h 49m7h 33m11h 46m16h 2m21h 33m24h23h 8m17h 32m13h 10m9h 1m7h 59m
Data source: Harstad daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Harstad

As autumn approaches, September winds in Harstad, Norway, display a gentle character, with an average wind speed of 2.7 m/s (6 mph). This slight decrease from the summer months reflects a transition, as the breezy days of July and August give way to the more subdued winds of fall. Notably, September's winds are comparable to those seen in early spring, suggesting a harmonious balance between the lingering warmth of summer and the impending chill of winter. With wind speeds remaining consistent throughout the month, residents and visitors can expect tranquil outdoor experiences, perfect for enjoying the stunning landscapes that Harstad has to offer as the leaves begin to change.

Average September Wind Speed in Harstad

The chart displays monthly wind speed patterns in Harstad, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec2.83.03.23.22.62.93.12.52.7 m/s2.82.72.8
Data source: Harstad September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Harstad Compares to Other Months

Weather in Harstad varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Harstad, focusing on differences in temperature, rainfall, humidity, and UV levels.

September and January present contrasting weather experiences. In September, temperatures range from a minimum of -1°C (31°F) to a pleasant maximum of 21°C (70°F), with an average of 9°C (48°F). This month sees significant rainfall, averaging 130 mm (5.1 in) over 17 days, accompanied by high humidity at 88%. In stark contrast, January is much colder, with temperatures plunging to a minimum of -24°C (-11°F) and an average of -5°C (24°F), peaking at just 8°C (46°F). Precipitation decreases slightly to 98 mm (3.9 in) over 14 days, while humidity remains high at 89%. For a more detailed overview of January weather, you can visit Harstad weather in January.

September and February present starkly contrasting weather conditions. In September, temperatures range from a pleasant minimum of -1°C (31°F) to a maximum of 21°C (70°F), averaging around 9°C (48°F). This month experiences significant rainfall, with 130 mm (5.1 in) over about 17 days, while humidity remains high at 88%. In contrast, February brings much colder temperatures, with minimums plunging to -20°C (-4°F) and average highs reaching only 7°C (45°F), resulting in an average temperature of -5°C (22°F). February is also relatively dry, with 107 mm (4.2 in) of precipitation spread across 14 days, but the humidity remains constant at 88%. For a closer look at February weather patterns, check out Harstad weather in February.

When comparing the weather in September and March, it's clear that these months present quite different conditions. In September, temperatures range from a minimum of -1°C (31°F) to a pleasant average of 9°C (48°F), peaking at a maximum of 21°C (70°F). The month is also characterized by substantial precipitation, accumulating to 130 mm (5.1 in) over about 17 days and a high humidity level of 88%.

In contrast, March sees much colder temperatures, with a minimum reaching -21°C (-6°F) and an average of -3°C (28°F), only climbing to a maximum of 8°C (46°F). Although it has a slightly higher total precipitation of 136 mm (5.4 in) across 19 days, the humidity remains marginally lower at 85%. This stark temperature difference highlights the transition from the late summer months to the grip of winter. For a more detailed look at March weather, visit Harstad weather in March.

September and April present contrasting weather experiences with notable differences in temperature and precipitation. In September, temperatures range from a chilly minimum of 1°C (34°F) to a mild maximum of 21°C (70°F), with an average of 9°C (48°F). The month also sees a significant amount of precipitation, totaling 130 mm (5.1 in) across 17 days, and a high humidity level of 88%. In contrast, April experiences colder temperatures, with a minimum of -12°C (11°F) and a maximum of 17°C (62°F), averaging only 1°C (34°F). Precipitation is slightly lower at 100 mm (3.9 in) over 18 days, accompanied by a humidity of 83%. For more detailed insights into April's climate, you can visit Harstad weather in April.

In comparison to September, May generally experiences cooler temperatures, with an average of 6°C (42°F), compared to September's milder average of 9°C (48°F). Despite having a similar maximum temperature of 22°C (71°F), May starts with lower minimum temperatures, reaching down to -6°C (22°F), while September has a minimum of -1°C (31°F). Precipitation levels are also lower in May, with 85 mm (3.4 in) falling over 15 days compared to September's 130 mm (5.1 in) over 17 days. Additionally, the humidity in May is slightly lower at 77%, in contrast to September's much higher 88%. For more detailed insights, you can check Harstad weather in May.

When comparing the weather in September and June, notable differences emerge. September generally has a cooler temperature range, with minimums dropping to -1°C (31°F) while averaging at 9°C (48°F) and peaking at 21°C (70°F). In contrast, June tends to be slightly warmer, with temperatures ranging from a minimum of 1°C (34°F) to an average of 10°C (51°F) and a maximum of 23°C (74°F). Precipitation levels are somewhat similar, with September receiving 130 mm (5.1 in) and June slightly less at 117 mm (4.6 in), both occurring over 17 days. Additionally, September experiences higher humidity at 88% compared to June's 82%. For more detailed information, you can refer to Harstad weather in June.

When comparing the weather in September and July, a noticeable difference in temperatures and precipitation patterns emerges. September experiences cooler temperatures with a minimum of -1°C (31°F) and an average of 9°C (48°F), peaking at 21°C (70°F). In contrast, July boasts milder weather, with minimum temperatures at 6°C (43°F), an average of 13°C (55°F), and maximums reaching 28°C (82°F). Precipitation is more frequent in September, with 130 mm (5.1 in) over 17 days compared to July's 101 mm (4.0 in) over 13 days. The humidity levels also reflect the transition, with September at 88% and July at 83%. For more detailed insights, you can check out Harstad weather in July.

In comparing the weather of September and August, September experiences notably cooler temperatures, with a minimum of -1°C (31°F) and an average of 9°C (48°F), in contrast to August's milder lows of 4°C (40°F) and an average of 12°C (54°F). The maximum temperatures also reflect this shift, dropping from August's high of 27°C (81°F) to September's peak of 21°C (70°F). Although September has slightly higher precipitation at 130 mm (5.1 in) over 17 days compared to August's 127 mm (5.0 in) spread across 20 days, it is accompanied by increased humidity, averaging 88% versus August's 84%. For more detailed information, check out Harstad weather in August.

In September, temperatures gradually transition from a minimum of -1°C (31°F) to a maximum of 21°C (70°F), with an average of 9°C (48°F). The month experiences considerable rainfall, totaling 130 mm (5.1 in) over 17 days, accompanied by high humidity at 88%. In contrast, October brings cooler temperatures, with lows reaching -7°C (20°F) and highs of 17°C (62°F), settling at an average of 4°C (39°F). Rainfall decreases slightly to 103 mm (4.0 in) over 16 days, while humidity remains consistent at 88%. This transition from the warmer, wetter days of September to the cooler, drier conditions of October highlights the shifting seasons. For more detailed insights on October weather, check out Harstad weather in October.

September and November showcase a noticeable transition in weather patterns. In September, temperatures range from a mild minimum of -1°C (31°F) to a pleasant maximum of 21°C (70°F), with an average of 9°C (48°F). The month experiences 130 mm (5.1 in) of precipitation over 17 days and maintains a high humidity level of 88%.

In contrast, November brings a much cooler climate, with temperatures plummeting to a minimum of -20°C (-4°F) and an average of 0°C (33°F), peaking at a maximum of 10°C (51°F). Despite slightly lower precipitation at 109 mm (4.3 in) over 19 days, the humidity remains relatively stable at 87%. The stark differences in temperature and overall feel of each month illustrate the shift into colder winter conditions. For more detailed insights, you can check Harstad weather in November.

When comparing the weather in September and December, significant differences emerge. In September, temperatures typically range from a chilly -1°C (31°F) at night to a pleasant 21°C (70°F) during the day, with an average temperature of 9°C (48°F). The month is also marked by higher precipitation, totaling 130 mm (5.1 in) over 17 days, with humidity levels at 88%. In contrast, December brings much colder temperatures, with a minimum of -19°C (-2°F) and a maximum of 8°C (46°F), averaging -3°C (26°F). Precipitation decreases slightly to 97 mm (3.8 in) over 16 days, and humidity remains relatively stable at 87%. For more specific details about December weather in this region, you can check Harstad weather in December.

Compare Harstad's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Harstad

As September unfolds in Harstad, the transition from the warmth of summer to the crisp embrace of autumn becomes evident. Temperatures dip significantly compared to the warmer months, with chilly nights hinting at the impending cold season. The increased precipitation, averaging over half an inch on many days, contributes to the lush, vibrant landscape, setting the stage for the beautiful autumn colors that will soon dominate the scenery. High humidity levels further enhance the feeling of freshness in the air, making it a month of notable contrasts. If you're interested in understanding how Harstad's climate evolves throughout the year, explore more details here: Harstad Climate.