Last updated: August 27, 2025
September in Arendal, Norway offers a diverse mix of weather, characterized by a maximum temperature reaching up to 26°C (80°F), while the average temperature hovers around a cool 13°C (56°F). This month welcomes the crispness of autumn, with lows dipping to 2°C (36°F). Rainfall is a frequent visitor, totaling 118 mm (4.6 in) across approximately 13 days, resulting in a notably high humidity level of 86%. Whether you’re exploring the vibrant local culture or marveling at the stunning coastal scenery, be prepared for a blend of pleasant warmth and refreshing showers!
In September, Arendal experiences a notable shift towards milder weather as summer transitions into autumn. With minimum temperatures averaging around 2°C (36°F) and maximums reaching up to 26°C (80°F), the month offers a comfortable warmth that invites outdoor activities. The average temperature hovers at 13°C (56°F), marking it as one of the cooler yet pleasant months of the year. As the days gradually shorten, this transitional period showcases a delightful balance of warm days and crisp evenings, making it an ideal time for exploring the beautiful coastal landscapes of Norway before winter sets in.
In September, Arendal, Norway experiences a notable increase in precipitation, with 118 mm (4.6 in) of rain spread over 13 days. This surge marks the highest monthly rainfall recorded for the year, transitioning the area from the relatively mild summer months to the onset of autumn's wetter climate. Compared to the preceding months, September's precipitation outpaces both August's 92 mm and May's 88 mm, highlighting a clear shift towards more frequent and intense rainfall as the year progresses. As the days grow shorter and temperatures dip, the increase in precipitation foreshadows the wetter months ahead, particularly October, which sees an even greater total of 157 mm (6.2 in) over 15 days. This trend underscores the characteristic climate pattern of the region, where late summer often gives way to a robust fall rain season.
In September, Arendal experiences a notable humidity increase to 86%, marking a transition from the drier summer months. This rise reflects a trend where the humidity levels are generally higher as autumn approaches, following the mild conditions of July and August, which saw consistent humidity around 74-78%. As the year progresses, the humidity tends to climb back up, with levels reaching a peak of 93% in January. The gradual shift back toward higher humidity levels in September hints at the impending winter, creating a moist atmosphere that can enhance the vibrant fall colors in the region.
As September rolls in, Arendal, Norway experiences a gradual decline in UV exposure, with the UV Index settling at 4, categorized as moderate. This represents a slight drop from the summer months, where values peaked at 7 during July. With a burn time of approximately 30 minutes, it’s crucial for residents and visitors alike to remain mindful of sun safety. As the days grow shorter and cooler, this transitional month offers a reminder of the summer sun's lingering effects. For those planning outdoor activities, staying informed about the UV Index remains essential; find more details at Arendal UV Index.
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As summer wanes in Arendal, Norway, September brings a lingering warmth with an impressive 292 hours of sunshine. This marks a notable shift as the region transitions from the longest days of July, basking in 478 hours, to the more mellow light of autumn. The sunlight starts to retreat steadily, with hours dropping to 244 by October and further to 137 in November. However, September stands as a vibrant bridge, allowing residents and visitors alike to savor the remnants of summer's radiance before the days shorten dramatically. Whether it's enjoying scenic coastal walks or gathering for late-season festivities, the golden hues of September offer a delightful experience in Arendal.
In September, the chances of enjoying sunny weather in Arendal, Norway dip to a modest 31%, making it one of the less favorable months for sun-seekers. This decline follows a summer that saw surprisingly better opportunities for sunshine, with August at 47% and July slightly ahead at 46%. As we transition from the vibrant summer months to the crispness of autumn, the likelihood of sunny days steadily decreases, evident from the gradual drop starting in April when the chances peaked at 62%. While September still offers opportunities for pleasant weather, it's clear that as autumn sets in, the sun becomes a more elusive companion in Arendal.
In Arendal, Norway, September marks a transitional phase as daylight begins to wane with 12 hours of sunshine, a noticeable shift from the vibrant summer months. Following the peak of 18 hours in June, daylight gradually decreases, reflecting the encroaching autumn. This month bridges the gap between the long, sun-filled days of summer and the shorter days ahead, making it a time when the landscape transforms into a rich tapestry of autumn colors. As October approaches, daylight shrinks further to 10 hours, suggesting that the longer days of summer have given way to cozy evenings and brisk, refreshing days. Embracing the gradual change in daylight, September invites residents and visitors alike to revel in the beauty of a shifting season.
As autumn approaches in Arendal, Norway, September brings a refreshing shift in the air with an average wind speed of 3.6 m/s (8 mph), re-establishing the gentle breezes reminiscent of the earlier months of spring. This slight uptick from the summer's calm, with consistent winds around 3.1 m/s (7 mph), hints at nature's preparation for the upcoming seasonal changes. Interestingly, September matches the winds of April, creating a harmonious balance as the natural world transitions. Looking ahead, October is set to raise the stakes with winds increasing to 4.3 m/s (10 mph), signaling a robust fall season ahead. Overall, the wind speed trends suggest a rhythm of serenity in summer giving way to a lively autumn breeze, inviting residents and visitors alike to embrace the unique charm of this coastal town.
Weather in Arendal varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Arendal, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. In September, temperatures range from a chilly 2°C (36°F) to a warm 26°C (80°F), with an average of 13°C (56°F). The month experiences 118 mm (4.6 in) of precipitation over 13 days, accompanied by high humidity at 86%. In contrast, January sees much colder conditions, with temperatures dipping to a minimum of -14°C (7°F) and only reaching a maximum of 10°C (50°F), averaging 1°C (35°F). Although precipitation decreases to 79 mm (3.1 in) over 11 days, humidity rises slightly to 93%. For a more detailed look at January weather, you can visit Arendal weather in January.
September and February present contrasting weather patterns. In September, temperatures range from a mild 2°C (36°F) at night to a comfortable 26°C (80°F) during the day, with an average of 13°C (56°F). The month also experiences significant rainfall, accumulating 118 mm (4.6 in) over 13 days, accompanied by high humidity levels at 86%. In contrast, February is much colder, with temperatures plunging to a minimum of -16°C (4°F) and averaging only 1°C (34°F), while maxing out at 12°C (53°F). Precipitation slightly decreases to 98 mm (3.9 in) over 12 days, and humidity rises to 91%. For more detailed insights, you can check Arendal weather in February.
In comparing the weather between September and March, we see notable differences in temperature and conditions. September typically enjoys milder temperatures, with minimums around 2°C (36°F) and averaging 13°C (56°F), peaking at a pleasant 26°C (80°F). It also experiences higher precipitation levels, averaging 118 mm (4.6 in) over 13 days, alongside a humidity rate of 86%. In contrast, March presents a chillier climate, with minimum temperatures plunging to -13°C (9°F) and averaging just 3°C (37°F), but it can still reach a maximum of 21°C (70°F). Precipitation in March is slightly lower, with 91 mm (3.6 in) over 11 days, while humidity remains relatively high at 88%. For more details on March weather, check out Arendal weather in March.
September and April present quite different weather experiences. In September, temperatures typically range from a minimum of 2°C (36°F) to a maximum of 26°C (80°F), with an average of 13°C (56°F). This month also sees considerable rainfall, with approximately 118 mm (4.6 in) over about 13 days, contributing to a relatively high humidity of 86%. In contrast, April is generally cooler, with temperatures dipping to a minimum of -7°C (20°F) and reaching a maximum of 20°C (68°F), averaging around 7°C (44°F). April features less rainfall, totaling around 39 mm (1.5 in) over 7 days, and maintains a slightly lower humidity at 83%. For more detailed insights on April weather, you can visit Arendal weather in April.
When comparing the weather in September and May, notable differences emerge in temperature, precipitation, and humidity. September generally experiences mild temperatures, ranging from a minimum of 2°C (36°F) to a maximum of 26°C (80°F), with an average of 13°C (56°F). In contrast, May has slightly cooler temperatures with a minimum of 0°C (32°F), an average of 12°C (53°F), and a maximum of 27°C (81°F). Precipitation levels are higher in September, totaling 118 mm (4.6 in) over 13 days, while May sees 88 mm (3.4 in) across just 10 days. Additionally, September's humidity is notably higher at 86%, compared to May's more comfortable 75%. For a deeper look into May weather, you can visit Arendal weather in May.
September weather tends to be cooler than June, with average temperatures ranging from a minimum of 2°C (36°F) to a maximum of 26°C (80°F), compared to June's temperatures, which range from a minimum of 5°C (42°F) to a maximum of 31°C (88°F). Additionally, September experiences higher humidity at 86%, compared to June's more comfortable 74%. While both months see a similar number of rainy days, September has more precipitation overall, receiving 118 mm (4.6 in), whereas June has 94 mm (3.7 in). For further insights on June weather, you can check Arendal weather in June.
In comparing the weather of September and July, September tends to be cooler with average temperatures ranging from a minimum of 2°C (36°F) to a maximum of 26°C (80°F), while July enjoys warmer conditions with averages between 9°C (48°F) and 29°C (85°F). Additionally, September experiences more precipitation, with 118 mm (4.6 in) over about 13 days compared to July's 94 mm (3.7 in) over 12 days. The humidity level is also higher in September at 86%, compared to July's 74%, making September feel wetter and cooler overall. For more specific details on July weather, you can visit Arendal weather in July.
In comparing the weather of September to that of August, September is notably cooler, with minimum temperatures dropping to 2°C (36°F) compared to August's milder minimum of 7°C (45°F). The average temperature in September is also lower at 13°C (56°F), whereas August enjoys an average of 16°C (62°F). Despite a slight increase in total precipitation to 118 mm (4.6 in) over 13 days in September, August has slightly less rainfall at 92 mm (3.6 in) over 12 days. Humidity levels are higher in September at 86% compared to 78% in August, contributing to a more damp feeling as the season transitions. For more details on August weather, you can check Arendal weather in August.
In comparing the weather between September and October, we see a noticeable shift in temperatures and precipitation patterns. September maintains a milder temperature range with averages around 13°C (56°F) and highs reaching 26°C (80°F), while October brings cooler conditions, with average temperatures dropping to 9°C (48°F) and maximums peaking at 17°C (64°F). Additionally, October experiences slightly higher precipitation levels, totaling 157 mm (6.2 in) over 15 days compared to September's 118 mm (4.6 in) across 13 days. The humidity also increases in October, reaching 92%, up from 86% in September. For more detailed weather insights, you can check Arendal weather in October.
September and November weather present a striking contrast, both in temperature and conditions. In September, temperatures range from a mild 2°C (36°F) at night to a pleasant 26°C (80°F) during the day, with an average of 13°C (56°F). Humidity is relatively high at 86%, and the month experiences around 118 mm (4.6 in) of precipitation over 13 days. In contrast, November brings significantly colder temperatures, with lows dipping to -8°C (17°F) and daytime highs reaching a maximum of 15°C (59°F), averaging just 5°C (41°F). Precipitation increases slightly to 121 mm (4.8 in) over 15 days, along with a marginal rise in humidity to 92%. For a detailed look at November weather patterns, you can visit Arendal weather in November.
September and December offer distinctly different weather experiences. In September, temperatures range from a minimum of 2°C (36°F) to a pleasant average of 13°C (56°F) and can reach a maximum of 26°C (80°F). This month sees around 118 mm (4.6 inches) of precipitation over approximately 13 days, with humidity levels at a comfortable 86%. In contrast, December brings much colder conditions, with temperatures dropping to a minimum of -12°C (10°F) and averaging just 2°C (36°F). The maximum temperature only reaches 12°C (53°F), while precipitation increases to 154 mm (6.0 inches) over around 18 days, and humidity levels rise slightly to 92%. For more detailed insights into the weather during this winter month, check out Arendal weather in December.
As September rolls into Arendal, the weather undergoes a noticeable transformation, bidding farewell to the warmth of summer. While temperatures can rise to a pleasant 26°C (80°F) during the day, the average settles around a cool 13°C (56°F), and chilly nights can drop to 2°C (36°F), reminding us that autumn is just around the corner. This month also brings higher humidity levels at 86%, contributing to a more muggy feel. With 13 days of precipitation totaling 118 mm (4.6 in), September is significantly wetter compared to the drier summer months, making it wise to carry an umbrella during your explorations. For more insights into how the weather patterns evolve throughout the year, check out Arendal Climate.