September Weather in Isafjoerdur, Iceland

Last updated: March 17, 2025

In September in Ísafjörður, Iceland, the weather offers a captivating blend of cool temperatures and frequent rainfall. The maximum highs reach a crisp 13°C (56°F), while the average hovers around a chilly 6°C (44°F), dipping as low as -3°C (28°F) on some nights. Rainfall is notable, with a total precipitation of 155 mm (6.1 in) spread across approximately 20 days, creating a damp yet refreshing atmosphere. The humidity levels soar to 89%, accentuating the coolness of the air and providing a true taste of Iceland's unique maritime climate. As summer transitions to autumn, the weather in Ísafjörður invites adventurers to experience its brisk beauty and vibrant landscapes.

September Temperature in Isafjoerdur

In September, Ísafjörður, Iceland, begins to feel the cool embrace of autumn, with temperatures dropping as summer fades. The month experiences a minimum of -3°C (28°F) and an average of 6°C (44°F), offering a refreshing change from the milder warmth of August. As the leaves start to turn, the maximum temperature reaches a comfortable 13°C (56°F), signaling the transition to the colder months ahead. This pattern of declining temperatures mirrors the gradual shift witnessed from the balmy summer highs, presenting a perfect opportunity for visitors to enjoy the stunning natural beauty of the region as it shifts into its vibrant autumnal hues.

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

The chart illustrates September temperature patterns in Isafjoerdur, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec283029343844484843383230
Data source: Temperature data for Isafjoerdur 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 Isafjoerdur

In September, Isafjoerdur experiences a significant uptick in precipitation, with 155 mm (6.1 in) of rainfall making it the wettest month of the year. This spike coincides with an increase in rainy days, as 20 days of precipitation contribute to a distinctly soggy atmosphere. The lush landscapes are revitalized after the drier summer months, where rainfall hovered around 71 to 79 mm. This trend signifies the onset of autumn, bringing both the promise of colorful foliage and the preparation for the harsher winter ahead. As with most months, the rain in September plays a crucial role in shaping the region's unique ecological tapestry, offering a refreshing contrast to the drier spells seen earlier in the year.

September Precipitation Trends in Isafjoerdur

The chart displays monthly precipitation patterns in Isafjoerdur, 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.
JanFebMarAprMayJunJulAugSepOctNovDec12713110911377717976155130116127
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Isafjoerdur

In Isafjoerdur, Iceland, September maintains a notable humidity level of 89%, mirroring the moist atmosphere commonly experienced throughout the year. Observations show a slight decrease in humidity during the summer months, with June hitting its lowest at 85%, but as autumn approaches, humidity levels creep back up, reflecting the region's persistent dampness. With consistency in humidity levels across the transitional seasons—from 89% in January and February to 88% in October—it’s clear that Isafjoerdur's climate remains predominantly humid, fostering a unique environment rich in natural beauty and vibrant landscapes.

September Average Humidity in Isafjoerdur

This chart illustrates the average monthly humidity levels in Isafjoerdur, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec89%89%90%86%87%85%88%89%89%88%87%87%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Isafjoerdur

In September, Isafjoerdur strikes a balance in UV exposure, sporting a UV Index of 3, which falls into the moderate category. As summer fades, the burn time is approximately 30 minutes, allowing for enjoyable outdoor activities while still emphasizing the importance of sun protection. This slight decrease from the peak summer months highlights the gradual transition into the cooler season, where UV levels remain relatively manageable. Overall, September provides a comfortable climate, but visitors should remain aware of changing UV conditions that can occur as the days grow shorter. For more details on UV levels throughout the year, check out the Isafjoerdur UV Index.

Maximum UV Index Levels in Isafjoerdur for September

The chart shows the monthly maximum UV Index (UVI) for Isafjoerdur 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.
JanFebMarAprMayJunJulAugSepOctNovDec112456543211
Data source: Isafjoerdur 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 Isafjoerdur

As summer fades into autumn, September in Isafjoerdur, Iceland, brings a gentle retreat from the abundant brightness of the earlier months. With 152 hours of sunlight, September marks a significant decline from the summer peak of over 324 hours in May and 285 hours in June, yet it still offers a pleasant glow as the days grow shorter. This tranquil time of year beautifully bridges the vibrant energy of summer with the quietude of winter, showcasing the dynamic shifts in daylight that Iceland experiences. As the months progress towards the stark light of October, which dips to 100 hours, the subtle transition paints the landscape in soft, autumnal hues, making September an ideal moment for reflection and exploration.

Monthly Sunshine Duration in Isafjoerdur: September Highlighted

The September sunshine duration represents the total number of hours Isafjoerdur 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.
JanFebMarAprMayJunJulAugSepOctNovDec17h60h157h224h324h285h267h243h152h100h36h8h
Data source: Isafjoerdur September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Isafjoerdur During September

In Isafjoerdur, Iceland, the likelihood of enjoying sunny weather in September stands at a modest 10%, aligning closely with the cooler months but showing a distinct trend of increased sunshine as summer approaches. Notably, while the summer months of May and April boast higher chances of sunshine—34% and 21% respectively—the subsequent months, July and August, see a sharper decline. This pattern continues into September, marking a transition from the vibrant summer days toward the unpredictable fall weather. Overall, visitors should remain optimistic yet prepared for the region's characteristic variability, as the promise of sun dips as the year wanes.

Percentage of Sunny Days in September in Isafjoerdur

The chart illustrates the percentage of sunny days in Isafjoerdur 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 Isafjoerdur experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec20%8%10%21%34%19%12%14%10%17%15%15%
Data source: Isafjoerdur September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Isafjoerdur in September

In September, daylight in Ísafjörður, Iceland begins to wane after the abundant light of summer, offering about 13 hours of daylight. This marks a gradual transition from the long, sunlit days of June and July, where daylight peaked at an impressive 23 and 20 hours, respectively. As autumn unfolds, the daylight shrinks further, reminiscent of early spring, with April's bright 15 hours providing a sense of continuity before the inevitable descent into winter's shorter days. Following September, the daylight dips significantly, plunging to just 9 hours in October, foreshadowing the long, dark months ahead. Overall, September presents a bittersweet balance of lingering brightness and the encroaching shadows of the colder season, making it a unique time to experience Iceland's stunning autumn scenery.

Average Daylight Hours in Isafjoerdur for September

The chart illustrates the variation in daylight duration in Isafjoerdur throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec4h 36m8h 12m11h 49m15h 29m19h 25m23h 29m20h 49m16h 41m13h9h 25m5h 44m3h
Data source: Isafjoerdur daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Isafjoerdur

In September, Isafjoerdur experiences a notable uptick in wind speed, averaging 5.4 m/s (12 mph), marking a transition towards the more bracing conditions of autumn. This increase stands in contrast to the warmer, calmer days of August, where winds dipped to just 3.0 m/s (7 mph). As summer wanes, the winds begin to pick up, a trend that continues into October with an average of 6.1 m/s (14 mph). This seasonal shift not only heralds the onset of fall but also invigorates the picturesque landscapes of Iceland, as nature prepares for the winter ahead. The fluctuating wind patterns throughout the year highlight the dynamic climate of the region, making September a particularly vibrant time to experience the raw beauty of Isafjoerdur.

Average September Wind Speed in Isafjoerdur

The chart displays monthly wind speed patterns in Isafjoerdur, 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.14.35.33.73.94.53.73.05.4 m/s6.14.64.2
Data source: Isafjoerdur September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Isafjoerdur Compares to Other Months

The weather in Isafjoerdur changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Isafjoerdur and find detailed weather information for every month.

In comparing the weather between September and January, notable differences in temperature and precipitation can be observed. September experiences milder temperatures, averaging around 6°C (44°F) with a maximum of 13°C (56°F), while January brings much colder conditions, with an average of -2°C (29°F) and a maximum of 8°C (47°F). Precipitation remains relatively high in both months, with September receiving 155 mm (6.1 in) and January slightly less at 127 mm (5.0 in), yet both months have around 20 days of precipitation and maintain the same high humidity level of 89%. For more details on the January weather, you can visit Isafjoerdur weather in January.

September and February present distinctly different weather patterns. In September, temperatures range from a chilly -3°C (28°F) at night to a mild 13°C (56°F) during the day, with an average of 6°C (44°F). The month experiences considerable rainfall, with 155 mm (6.1 in) across 20 days, contributing to a high humidity level of 89%. In contrast, February is colder, with minimum temperatures dropping to -13°C (8°F) and an average of -1°C (30°F). The daytime highs reach only 7°C (44°F), and despite slightly lower precipitation at 131 mm (5.2 in), it still occurs over the same number of days. Humidity remains constant at 89%, creating a persistent chill in the air. For more details, visit Isafjoerdur weather in February.

When comparing the weather in September and March, notable differences emerge despite both months experiencing cool temperatures and high humidity. In September, temperatures range from a minimum of -3°C (28°F) to a maximum of 13°C (56°F), with an average of 6°C (44°F) and precipitation of 155 mm (6.1 in) over 20 days. Conversely, March sees colder conditions, with temperatures dipping as low as -13°C (10°F) and peaking at 6°C (44°F), averaging -2°C (29°F). This month receives less precipitation, totaling 109 mm (4.3 in) over 19 days, yet maintains a similarly high humidity level of 90%. For more specifics on March weather, you can visit Isafjoerdur weather in March.

In September, the weather begins to transition into autumn, with temperatures ranging from a minimum of -3°C (28°F) to a maximum of 13°C (56°F), resulting in an average of 6°C (44°F). Precipitation is significant, totaling 155 mm (6.1 in) over 20 days, with a high humidity level of 89%. In contrast, April presents a colder climate, with temperatures dipping as low as -12°C (10°F) and only reaching a maximum of 12°C (53°F). The average temperature in April is 1°C (34°F), and while precipitation is lower at 113 mm (4.4 in) over 16 days, humidity is slightly less at 86%. For more details on April weather specifically, you can visit Isafjoerdur weather in April.

In comparing the weather between September and May, one can observe notable differences despite their similar maximum temperatures of around 13°C (56°F). September experiences slightly higher average temperatures, sitting at 6°C (44°F), compared to May's average of 4°C (39°F). Additionally, September sees more precipitation, with 155 mm (6.1 in) falling over 20 days, while May has only 77 mm (3.0 in) across 14 days. Humidity levels are also comparable, with September having 89% and May at 87%. For a more detailed look at May weather, you can visit Isafjoerdur weather in May.

In September, the weather is noticeably colder compared to June, with temperatures ranging from a minimum of -3°C (28°F) to a maximum of 13°C (56°F) and an average of 6°C (44°F). Additionally, September experiences significantly more precipitation, totaling 155 mm (6.1 in) over approximately 20 days, while June sees only 71 mm (2.8 in) of rain over 14 days. Humidity levels are also slightly higher in September at 89%, compared to June's 85%. For more detailed insights into the weather in June, you can check Isafjoerdur weather in June.

The weather in September is notably cooler compared to July, with average temperatures only reaching 6°C (44°F), down from 9°C (48°F) in July. July boasts milder temperatures, with a maximum of 17°C (62°F), while September sees a high of just 13°C (56°F). Additionally, September experiences significantly more precipitation, receiving 155 mm (6.1 in) over 20 days, compared to July's 79 mm (3.1 in) over 14 days. The humidity remains fairly consistent, with September at 89% and July slightly lower at 88%. For more details on the weather in July, visit Isafjoerdur weather in July.

In comparing the weather of September and August, we see a notable drop in temperatures as summer transitions into autumn. While August features a milder climate with average temperatures reaching around 9°C (48°F) and maximums of 17°C (62°F), September experiences cooler conditions, with average temperatures of just 6°C (44°F) and a maximum of 13°C (56°F). Additionally, September is significantly wetter, receiving 155 mm (6.1 in) of precipitation over 20 days, compared to August’s 76 mm (3.0 in) over 14 days. The humidity remains relatively consistent, with September peaking at 89% compared to August's 88%. For a detailed look at August weather conditions, visit Isafjoerdur weather in August.

In September, temperatures range from a chilly -3°C (28°F) at night to a mild average of 6°C (44°F) during the day, with a maximum of 13°C (56°F). This month sees an abundance of rainfall, totaling 155 mm (6.1 in) over 20 days, and it experiences high humidity levels at 89%.

In contrast, October brings slightly colder temperatures, with a minimum of -6°C (22°F) and an average of 3°C (38°F), while the maximum dips to 10°C (49°F). The precipitation decreases to 130 mm (5.1 in), also spread over 20 days, and humidity remains marginally lower at 88%. For more detailed information, check out Isafjoerdur weather in October.

September and November present notably different weather conditions. In September, temperatures range from a minimum of -3°C (28°F) to a maximum of 13°C (56°F), with an average of 6°C (44°F). The month sees substantial precipitation, totaling 155 mm (6.1 in) over 20 days, accompanied by high humidity at 89%. In contrast, November is colder, with temperatures dipping to a minimum of -9°C (16°F) and averaging around 0°C (33°F), peaking at 10°C (51°F). Rainfall decreases to 116 mm (4.6 in) spread over 19 days, and humidity remains slightly lower at 87%. To learn more about the specific weather conditions for November, you can check the link: Isafjoerdur weather in November.

In comparing the weather of September and December, notable differences emerge. September experiences milder temperatures, with a minimum of -3°C (28°F) and an average of 6°C (44°F), while December sees lower temperatures with a minimum of -12°C (10°F) and an average of -1°C (30°F). Precipitation is slightly higher in September at 155 mm (6.1 in) over 20 days compared to December's 127 mm (5.0 in) across 21 days. Humidity levels are also quite close, with September at 89% and December at 87%. For more detailed information about December's weather, you can refer to Isafjoerdur weather in December.

Compare Isafjoerdur's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Isafjoerdur

As September arrives in Isafjoerdur, the weather signals a transition, bringing with it cooler temperatures and a noticeable uptick in precipitation, with rain shaping much of the month. The blend of crisp air and high humidity creates an atmosphere that is both refreshing and moody, setting the stage for the vibrant autumn colors to emerge. Unlike the milder summer months, September's average temperatures dip, inviting a cozy retreat indoors while the dynamic weather patterns dance outside. This shift serves as a reminder of the approaching winter, making September a unique month that showcases both the beauty and unpredictability of Isafjoerdur's climate. For more detailed insights, visit Isafjoerdur Climate.