Last updated: August 27, 2025
In September, the weather in Alta, Norway presents a captivating mix of cool temperatures and frequent precipitation. With maximum temperatures reaching up to 21°C (70°F), the average hovers around a brisk 7°C (45°F), while nights can dip to a chilly -3°C (28°F). The month sees about 76 mm (3.0 in) of rainfall, distributed across 15 days, contributing to the region's lush landscapes. High humidity levels of 93% add to the crispness of the air, creating a uniquely refreshing atmosphere that characterizes this enchanting northern locale. Visitors can expect a blend of vibrant autumn hues amidst the shifting weather, making September an intriguing time to explore Alta.
In September, Alta, Norway, transitions from the warm embrace of summer to the crispness of autumn, showcasing a notable dip in temperatures. With minimums dropping to -3°C (28°F) and averaging around 7°C (45°F), the days become noticeably cooler. However, the maximum temperature can still reach a pleasant 21°C (70°F), allowing for some late-season outdoor adventures. This month serves as a bridge, as the warm summer days fade, making way for the cool, fresh air that characterizes the approaching fall. As the leaves begin to change, September offers a stunning backdrop for nature lovers while hinting at the colder months ahead.
September in Alta, Norway, experiences a noteworthy transition in its weather patterns, registering 76 mm (approximately 3.0 inches) of precipitation over 15 days. This marks a slight dip compared to the preceding months of August and July, both of which saw higher rainfall totals—92 mm and 83 mm, respectively. As autumn approaches, the weather begins to cool, yet September still retains a moderate amount of rainfall that contributes to the lush, vibrant landscape typical of this northern region. Observing the trend, precipitation tends to peak in late summer, with September acting as a transitional month where the frequency of rainy days remains consistent, echoing the wetter summer months while paving the way for the drier autumn ahead.
In Alta, Norway, September marks a subtle shift as the air retains a humidity level of 93%, a slight increase from the summer months. This uptick reflects the transition into autumn, where the crispness of the air is still tinged with the lingering warmth of late summer. As the year progresses, humidity begins its inevitable climb, starting at a comfortable 84% in May and reaching a peak of 100% by January. The steady increase throughout the fall months foreshadows the cold, damp winter ahead, while September's conditions serve as a reminder of the region’s dynamic climate, where each month reveals a unique interplay between moisture and temperature.
As the seasons change in Alta, Norway, so does the UV Index, reflecting the evolving strength of the sun. In September, the UV Index drops to 2, indicating a low exposure category with a burn time of 45 minutes—a comfortable range for outdoor activities without intense sun damage. This follows a summer peak where the index reached 5 in July, suggesting that while the days are still pleasant, the sun's rays are becoming milder. The transition into fall signals a gradual retreat of stronger UV levels, making September an ideal month for cautious sun enjoyment. For more detailed insights, check out the Alta UV Index.
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As summer transitions into autumn, September in Alta, Norway brings a delightful shift in daylight, with approximately 237 hours of sunshine illuminating the landscape. This is a noticeable drop from the sun-drenched days of July, which boasts the year’s peak at 414 hours, but still holds onto a vibrant glow. The month serves as a bridge, linking the lush, bright months of summer with the dimming days of October, which sees a significant decline to just 142 hours. As nature prepares for the cold embrace of winter, September invites residents and visitors alike to savor the lingering warmth before the long nights set in, making it a cherished moment to enjoy the breathtaking landscapes bathed in golden light.
In Alta, Norway, September showcases a 20% chance of sunny weather, marking a slight uptick from the summer months. While July and June enjoy a higher probability of sunshine at 24% and 27%, respectively, September represents a transition into the cooler autumn days. This month is characterized by a gradual shift from the sun-drenched summer, with August dropping to 19%, hinting at the inclement weather to come. As the year progresses towards winter, the likelihood of sunny spells decreases, seen in the notable drop to 10% in October. In this context, September's sun signifies a lingering warmth, inviting those who cherish outdoor activities to embrace the last vestiges of summer before the long nights of winter set in.
As summer gracefully transitions into autumn, September in Alta, Norway marks a significant shift in daylight duration. Following the midnight sun days of June, where light envelops the sky for 24 hours, the days gradually shorten. By September, residents enjoy around 13 hours of daylight, a noticeable decline from the 18 hours in August. This decline signals the approach of shorter days, in stark contrast to the lengthy, sun-drenched hours of summer. The month serves as a gentle reminder of the changing seasons, as nature prepares for the crisp and dark winter months ahead, culminating in the near-total absence of daylight by December.
As summer wanes into autumn, September's winds in Alta, Norway usher in a noticeable change, with an average speed of 3.0 m/s (7 mph), mirroring the gusts of October. This increase marks a notable crescendo compared to the lighter breezes of the preceding months, which hovered around 2.0 to 2.6 m/s. The gentle summer seems to give way to a brisker atmosphere, hinting at the seasonal transition and the invigorating chill of fall. With winds picking up speed, September stands out as a pivotal moment, gracefully bridging the tranquility of summer with the crisp embrace of autumn.
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.
September and January present starkly contrasting weather conditions. In September, temperatures range from a chilly -3°C (28°F) at night to a pleasant 21°C (70°F) during the day, with an average of 7°C (45°F). The month sees significant rainfall, totaling 76 mm (3.0 in) over about 15 days, accompanied by high humidity at 93%. In contrast, January plunges into much colder territory, with night temperatures dropping to a frigid -28°C (-17°F) and a max of just 5°C (42°F), averaging -9°C (16°F). Although January experiences less precipitation at 46 mm (1.8 in) over 11 days, it boasts a whopping 100% humidity. For more detailed information, you can explore Alta weather in January.
September and February present stark contrasts in weather conditions. In September, temperatures range from a chilly -3°C (28°F) at the lowest to a mild 21°C (70°F) at the highest, with an average of 7°C (45°F). The month experiences about 76 mm (3.0 inches) of precipitation over 15 days and a relatively high humidity of 93%. In contrast, February is much colder, with minimum temperatures plummeting to -25°C (-12°F) and an average of -9°C (16°F), peaking at just 6°C (44°F). Precipitation decreases to 48 mm (1.9 inches) across 12 days, and humidity rises slightly to 99%. For more specific details about February weather in Alta, visit Alta weather in February.
In comparing the weather between September and March, a stark contrast emerges. September tends to be milder, with temperatures ranging from a minimum of -3°C (28°F) to a maximum of 21°C (70°F) and an average of 7°C (45°F). It experiences higher humidity at 93% and a significant amount of precipitation totaling 76 mm (3.0 in) over 15 days. In contrast, March is notably colder, with temperatures dropping to a minimum of -22°C (-8°F) and peaking at just 7°C (45°F), giving an average temperature of -6°C (22°F). Despite slightly lower precipitation at 59 mm (2.3 in) across 16 days, March has a higher humidity level at 95%. For more detailed insights about conditions during this time, check Alta weather in March.
When comparing the weather between September and April, notable differences emerge. September enjoys milder temperatures, with averages around 7°C (45°F) and a maximum of 21°C (70°F), while April experiences colder conditions, averaging just -1°C (30°F) and reaching a high of 14°C (57°F). Precipitation is more frequent in September, totaling 76 mm (3.0 in) over 15 days, compared to April’s 55 mm (2.2 in) over 14 days. Humidity levels are slightly higher in September at 93%, compared to 91% in April. For more detailed information about April's weather, please visit Alta weather in April.
In comparing the weather between September and May, September generally presents milder temperatures with a minimum of -3°C (28°F) and an average of 7°C (45°F), peaking at 21°C (70°F). In contrast, May tends to be cooler overall, with temperatures dipping as low as -8°C (18°F) and averaging 3°C (38°F), while the maximum reaches only 19°C (67°F). September also experiences more precipitation at 76 mm (3.0 in) over 15 days, compared to May's 63 mm (2.5 in) spread out over 17 days. Humidity levels are notably higher in September at 93%, whereas May has a humidity level of 84%. For an in-depth look at weather conditions in May, you can visit Alta weather in May.
September and June present contrasting weather conditions. In September, temperatures range from a chilly -3°C (28°F) at night to a comfortable maximum of 21°C (70°F) during the day, while June features slightly milder temperatures with a minimum of -3°C (27°F) and a maximum of 24°C (76°F). Precipitation is fairly common in both months, with September receiving 76 mm (3.0 in) over 15 days and June experiencing a bit more with 89 mm (3.5 in) across 17 days. Moreover, September has higher humidity levels at 93%, compared to June's 84%. For a detailed look at June weather in Alta, you can visit Alta weather in June.
In comparing the weather between July and September, it's clear that July tends to be warmer with average temperatures ranging from 3°C (38°F) to a maximum of 27°C (81°F), while September shows a cooler range with minimum temperatures dropping to -3°C (28°F) and a maximum of 21°C (70°F). Although September has slightly less precipitation at 76 mm (3.0 in) compared to July's 83 mm (3.3 in), it experiences rain on more days, totaling 15 days versus July's 13. Additionally, September has a higher humidity level at 93%, compared to July's 85%. For a more detailed look at July weather in Alta, you can visit Alta weather in July.
In comparing the weather of September and August, September experiences cooler overall temperatures, with a minimum of -3°C (28°F) and an average of 7°C (45°F), contrasted with August's milder range of 1°C (35°F) as a minimum and an average of 11°C (52°F). The maximum temperatures in September reach 21°C (70°F), significantly lower than August’s high of 28°C (83°F). While both months see precipitation on 15 days, September has slightly less rain at 76 mm (3.0 in) compared to August's 92 mm (3.6 in). Humidity levels remain high in both months, with September at 93% and August at 90%. For a detailed overview of August weather, you can visit Alta weather in August.
In comparing the weather between September and October, a clear cooling trend emerges. September experiences milder temperatures, with a minimum of -3°C (28°F) and an average of 7°C (45°F), while October sees a significant drop, featuring a minimum of -19°C (-2°F) and an average of 0°C (33°F). Despite this drop in temperature, October's precipitation totals are lower at 50 mm (2.0 in), occurring over 14 days, compared to September's 76 mm (3.0 in) across 15 days. Additionally, October brings a slight increase in humidity, peaking at 96% compared to September's 93%. For a more detailed look at conditions, you can check Alta weather in October.
In September, the weather is relatively mild, with temperatures ranging from a minimum of -3°C (28°F) to a maximum of 21°C (70°F), averaging around 7°C (45°F). The month experiences considerable precipitation of 76 mm (3.0 in) over 15 days, accompanied by high humidity levels of 93%. In contrast, November marks a significant drop in temperature, with a minimum of -26°C (-15°F) and a maximum of only 7°C (44°F), averaging -4°C (24°F). Although November has less precipitation at 53 mm (2.1 in) over 14 days, the humidity increases to 99%, contributing to an even more intense cold. For more details, you can check Alta weather in November.
In comparing the weather of September and December, a stark contrast emerges. September boasts a milder temperature range, with minimums of -3°C (28°F) and maximums reaching 21°C (70°F), along with an average of 7°C (45°F). This month experiences significant precipitation, totaling 76 mm (3.0 in) across 15 days, alongside a high humidity level of 93%. In contrast, December is much colder, with temperatures dipping to a minimum of -24°C (-11°F) and an average of -8°C (18°F), peaking at just 4°C (39°F). The precipitation decreases to 39 mm (1.5 in) over 11 days, and the humidity remains at a maximum level of 100%. For more detailed insights about December weather in Alta, you can visit Alta weather in December.
As September unfolds in Alta, the weather takes on a distinct character, with cooler temperatures and increased precipitation setting it apart from the summer months. This shift heralds the arrival of fall, marked by brisk days where daytime maximums linger around a mild 21°C while chilly nights can dip down to -3°C. The air is filled with a palpable humidity of 93%, and rain becomes more frequent, with about 15 days of precipitation contributing to a total of 76 mm. This combination makes September a time of transition, inviting residents and visitors alike to embrace the beauty of nature's changing palette. For a more detailed look at the weather patterns, check out Alta Climate.