Last updated: August 27, 2025
In Alta, Sweden, September heralds the transition into autumn with a maximum temperature reaching 22°C (72°F), while the average temperature settles at a mild 13°C (56°F). The month experiences a minimum temperature of 3°C (38°F), showcasing the cool crispness typical of the season. Rainfall is a frequent visitor, contributing to a total precipitation of 52 mm (2.0 in) over approximately 10 days, resulting in an 85% humidity level that adds a refreshing touch to the air. As the foliage begins to change, September in Alta is marked by a unique blend of scenic beauty and atmospheric charm.
As September rolls into Alta, Sweden, the temperatures begin to transition from the summer warmth of August into the cooler embrace of autumn. The month presents a pleasant shift, with minimums hovering around 3°C (38°F) and an average temperature of 13°C (56°F), providing a comfortable setting for early fall activities. Daytime highs can reach up to 22°C (72°F), making it one of the last months to enjoy relatively mild days before the chill sets in. This gradual decline in temperatures signals a change in the landscape, as vibrant autumn colors start to dominate the scenery, inviting both locals and visitors to experience the serene beauty of Scandinavian nature in this tranquil time of year.
In September, Alta, Sweden experiences a moderate amount of precipitation, with 52 mm (2.0 in) recorded over approximately 10 days. This represents a slight decrease from the heavier rains of August, where 68 mm (2.7 in) fell across 12 days. September's rainfall marks a continuation of the late-summer pattern, as the region transitions into autumn, but it remains significantly lower than the upcoming months like October, which typically sees increased rainfall. This shift hints at the changing seasons, with wetter conditions poised to take hold as the days grow shorter and cooler. Notably, September's precipitation is consistent with a trend of variability throughout the year, emphasizing the unique climate characterizing Alta as it gracefully moves from the warmth of summer to the chill of winter.
As we transition into September in Alta, Sweden, the humidity begins to rise slightly to 85%, reflecting a shift from the summer’s drier conditions, where July and August boasted levels around 74% and 77%, respectively. This increase marks a trend as the lush, crisp autumn settles in, echoing the higher humidity levels of earlier months like January and February, which hover near 90%. September serves as a bridge, hinting at the return of the damp chill that will characterize the upcoming months, reinforcing the notable cyclical pattern of humidity in this northern locale. With nature's transition in full swing, Alta’s atmosphere is poised to embrace the seasonal changes ahead.
As autumn approaches in Alta, Sweden, the UV Index begins to decline, marking a notable shift in sun exposure. By September, the UV Index sits at a moderate 4, suggesting a burn time of approximately 30 minutes for fair-skinned individuals. This is a decrease from the high-index days of summer, where peak UV levels reached 7 in both June and July. With the sun's strength diminishing, it’s essential to still remain mindful of UV exposure, as even moderate levels can result in skin damage with prolonged unprotected exposure. For more details, check out the comprehensive UV data at Alta UV Index.
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As autumn sets in, September in Alta, Sweden offers a captivating transition from the warmth of summer to the cozy embrace of fall. The month basks in 312 hours of sunshine, showcasing a delightful abundance of light before the days start to shorten. This marks a notable decrease from the peak of 488 hours enjoyed in July, yet it remains a substantial amount compared to the darker months ahead. The trend of diminishing sunshine is evident as the year progresses, with the gradual descent into winter characterized by significant drops in daylight, ultimately leading to a modest 71 hours in January. However, September’s golden rays serve as a soothing reminder of the summer days, inviting both locals and travelers to revel in the beauty of nature before embracing the cooler, shorter days of autumn.
In September, the likelihood of experiencing sunny weather in Alta, Sweden drops to 27%, making it one of the less favorable months for sunshine compared to the vibrant months of June and July, which boast over 55% sunshine probability. This decrease follows the traditional summer peak, with August already showing a notable decline to 38%. While autumn approaches, the lingering effects of summer sun begin to fade, leading to a more cloud-laden sky as the region prepares for the cooler months ahead. Hence, if you're hoping for bright days, early September might still offer some sunshine, but as the month progresses, expect more overcast skies.
As summer transitions to autumn, September in Alta, Sweden offers a gentle decline in daylight, with about 12 hours of sunshine. This marks a shift from the peak brightness of June, which boasts a remarkable 18 hours. By September, the days begin to shorten, reflecting the gradual approach of winter. The daylight hours decrease steadily from the sun-drenched days of May and June, illustrating the natural rhythm of the seasons. Although September sees less sunlight than the vibrant summer months, the lingering warmth of early autumn still invites exploration and enjoyment of the stunning landscapes that define this northern region.
As September arrives in Alta, Sweden, a gentle shift in the wind begins to weave through the landscape, with an average wind speed of 4.8 m/s (11 mph). This marks a slight increase from the calmer days of summer, reflecting a transition from the low, soothing breezes of June and July, where speeds dropped to around 3.5 m/s (8 mph). As autumn settles in, the winds regain strength, hinting at the changing seasons that follow. Notably, October sees a more pronounced gust, reaching 5.8 m/s (13 mph), setting the stage for the brisk, invigorating winds typical of winter. Overall, September's winds act as a bridge, gracefully guiding us from the tranquility of summer towards the more vigorous character of the months ahead.
Weather in Alta varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Alta, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is generally mild, with temperatures ranging from a chilly 3°C (38°F) at night to a comfortable high of 22°C (72°F) during the day, accompanied by an average temperature of 13°C (56°F). The month experiences about 52 mm (2.0 in) of rainfall over approximately 10 days, while humidity levels hover around 85%. In stark contrast, January brings a significant chill, with temperatures plummeting to a minimum of -15°C (6°F) and a maximum of just 9°C (49°F), averaging 0°C (33°F). January's precipitation totals about 43 mm (1.7 in) spread across the same number of days, but the humidity is slightly higher at 90%, contributing to the crisp winter air. For a deeper look at January conditions, you can visit Alta weather in January.
The weather in September is generally milder than in February, with average temperatures ranging from a maximum of 22°C (72°F) to a minimum of 3°C (38°F), while February experiences much colder conditions, with highs only reaching 9°C (48°F) and lows dropping to -12°C (11°F). In September, the region sees about 52 mm (2.0 in) of precipitation over approximately 10 days, contrasted with February’s 38 mm (1.5 in) of precipitation over 9 days. Humidity levels are slightly higher in February at 88%, compared to 85% in September, which may contribute to the overall chill in the air during the winter month. For more detailed information, check out Alta weather in February.
September and March present distinctly different weather patterns, reflecting the transition from summer to autumn and winter to spring, respectively. In September, temperatures range from a mild 3°C (38°F) to a comfortable maximum of 22°C (72°F), accompanied by relatively high humidity at 85%. Precipitation is moderate, with about 52 mm (2.0 in) falling over approximately 10 days. In contrast, March experiences colder conditions, with temperatures dropping to a minimum of -10°C (14°F) and peaking at 14°C (57°F), resulting in an average temperature of just 2°C (35°F). Though precipitation is slightly lower at 44 mm (1.7 in) over 9 days, the humidity remains high at 89%. For more detailed information about the weather in March, you can visit Alta weather in March.
In September, the weather tends to be milder with average temperatures ranging from a minimum of 3°C (38°F) to a maximum of 22°C (72°F), creating a comfortable climate for outdoor activities. The month sees approximately 52 mm (2.0 in) of precipitation over about 10 days, accompanied by a consistent humidity level of 85%. In contrast, April brings cooler temperatures, with lows dropping to -5°C (24°F) and highs reaching only up to 17°C (62°F), suggesting a gradual transition into warmer months. Rain is less frequent in April, with about 25 mm (1.0 in) of precipitation occurring over 7 days, yet the humidity remains at 85%. For more details on April weather, check Alta weather in April.
September and May present a contrast in weather conditions. In September, temperatures range from a minimum of 3°C (38°F) to a maximum of 22°C (72°F), with an average of 13°C (56°F). The month is characterized by higher humidity at 85% and more frequent precipitation, averaging 52 mm (2.0 in) across approximately 10 days. In comparison, May experiences slightly cooler conditions with temperatures fluctuating from -2°C (29°F) to a maximum of 21°C (69°F), and an average temperature of 9°C (49°F). This month sees similar precipitation levels at 50 mm (2.0 in) but less frequent rainfall over about 9 days and lower humidity at 77%. For more details on May weather, you can visit Alta weather in May.
September and June exhibit distinct differences in weather patterns. In September, temperatures range from a chilly minimum of 3°C (38°F) to a comfortably warm maximum of 22°C (72°F), with an average of 13°C (56°F). The month is characterized by higher humidity at 85% and more frequent precipitation, totaling 52 mm (2.0 in) over about 10 days. In contrast, June offers milder conditions, with temperatures fluctuating between a minimum of 7°C (44°F) and a maximum of 23°C (75°F), averaging 15°C (60°F). Rainfall is slightly less in June at 44 mm (1.7 in), occurring over 7 days, and humidity levels are lower at 76%. For more details on June weather in Alta, you can refer to this link: Alta weather in June.
In comparing the weather of September and July, notable differences emerge in temperature and humidity levels. September experiences cooler temperatures, with a minimum of 3°C (38°F) and an average of 13°C (56°F), while July boasts milder conditions, starting at a minimum of 9°C (48°F) and averaging 17°C (64°F). Additionally, July's maximum temperatures reach up to 26°C (80°F), providing a warm contrast to September's peak of 22°C (72°F). Although both months receive comparable amounts of precipitation—52 mm (2.0 in) in September and 55 mm (2.1 in) in July—September tends to be more humid, with humidity levels at 85% compared to July's 74%. For a closer look at the weather patterns for summer, you can check Alta weather in July.
In comparing the weather of September to August, it’s evident that September is cooler, with average temperatures ranging from a minimum of 3°C (38°F) to a maximum of 22°C (72°F), compared to August’s warmer range of 8°C (47°F) to 27°C (81°F). September also experiences slightly more precipitation, totaling 52 mm (2.0 in) over approximately 10 days, whereas August has 68 mm (2.7 in) over 12 days. Additionally, September's humidity is higher at 85%, while August maintains a lower humidity level of 77%. For a closer look at August weather conditions, check out Alta weather in August.
September's weather tends to be milder, with average temperatures ranging from a minimum of 3°C (38°F) to a maximum of 22°C (72°F). It experiences about 52 mm (2.0 in) of precipitation over approximately 10 days, with humidity levels averaging 85%. In contrast, October brings a notable shift, with temperatures dropping significantly to a range of 0°C (32°F) to 16°C (60°F), and an average of 9°C (48°F). Precipitation increases to 76 mm (3.0 in) over 13 days, contributing to a slight rise in humidity, which reaches 89%. This shift in climate makes October feel much chillier and wetter compared to its predecessor. For more detailed information, you can check Alta weather in October.
September typically offers milder temperatures, with a minimum of 3°C (38°F) and an average of 13°C (56°F), reaching a maximum of 22°C (72°F). The precipitation level is around 52 mm (2.0 in) over about 10 days, and humidity hovers at a relatively high 85%. In contrast, November brings significantly cooler conditions, with a minimum temperature dropping to -7°C (20°F) and an average of 5°C (41°F), peaking at 14°C (57°F). Although precipitation remains similar at 50 mm (2.0 in), it occurs over slightly more days, totaling 11, and the humidity increases to 90%. For more specific weather details, you can check Alta weather in November.
In September, the weather is relatively mild, with temperatures ranging from a minimum of 3°C (38°F) to an average of 13°C (56°F), peaking at 22°C (72°F). During this month, precipitation is moderate at 52 mm (2.0 in) over approximately 10 days, and humidity levels are quite high at 85%. In contrast, December experiences much colder conditions, with temperatures plummeting to a minimum of -10°C (14°F) and an average temperature of just 2°C (35°F), reaching a maximum of 8°C (47°F). December also sees an increase in precipitation to 70 mm (2.8 in) over about 15 days, along with a slightly higher humidity level of 87%. For more specific weather details, you can refer to Alta weather in December.
As summer gradually fades, September in Alta ushers in a noticeable shift in weather, marked by cooler temperatures and increased humidity. This month showcases a pleasant average temperature that is a refreshing relief from the heat of July and August, with maximums cooling down significantly. Although rain becomes more frequent, with approximately ten rainy days, the surrounding natural beauty remains stunning against the soft light of early autumn. The 85% humidity adds a crispness to the air, highlighting the transition from summer warmth to the briskness of fall. Embrace the changing season and discover more about the climatic nuances by checking out Alta Climate.