September Weather in Larvik, Norway

Last updated: August 27, 2025

September in Larvik, Norway, presents a charming blend of early autumn weather, characterized by a maximum temperature of 21°C (70°F) and an average of 14°C (57°F). As the month progresses, nighttime lows can dip to a refreshing 7°C (44°F). Visitors should prepare for some rainfall, with 128 mm (5.1 in) of precipitation spread over approximately 13 days, contributing to the region’s lush landscapes. The humidity levels can reach a notable 86%, creating a crisp, invigorating atmosphere perfect for exploring the scenic beauty that Larvik has to offer.

September Temperature in Larvik

As September unfolds in Larvik, Norway, the lingering warmth of summer gradually gives way to the crispness of autumn. With min temperatures settling at a mild 7°C (44°F), the average temperature rises to a comfortable 14°C (57°F), peaking at a pleasant 21°C (70°F) during the day. This transition highlights a noticeable shift from the preceding months, as September marks a decline from the height of summer's warmth in August, yet still retains a hint of lingering summer. The mild evenings encourage outdoor activities while showcasing the vibrant hues of the season's changing leaves, making it an enchanting time to experience the beauty of Larvik.

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

The chart illustrates September temperature patterns in Larvik, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Larvik, 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).
JanFebMarAprMayJunJulAugSepOctNovDec363437435261646257504337
Data source: Temperature data for Larvik 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 Larvik

In September, Larvik, Norway experiences a notable spike in precipitation, receiving an average of 128 mm (5.1 in) of rain over 13 days. This significant increase marks September as the wettest month of the year, foreshadowing the wetter conditions that persist into the fall and winter months. Compared to the relatively moderate rainfall in the summer, with August and July averaging around 81 mm (3.2 in) and 84 mm (3.3 in) respectively, September's precipitation not only highlights a departure from the drier summer season but also sets the stage for the increased rainfall that follows in October. The pattern suggests a seasonal transition, where the refreshing summer rains give way to the more substantial downpours that characterize the approaching colder months.

September Precipitation Trends in Larvik

The chart displays monthly precipitation patterns in Larvik, 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 Larvik, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec7275733470818481128144122129
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Larvik

September in Larvik, Norway, marks a notable shift in humidity levels as the summer months give way to the crispness of autumn. After a relatively dry spell in July and June, where humidity dips to 74%, September sees a significant increase to 86%, setting the stage for the cooler, wetter months ahead. This rise not only signals the onset of fall but also reflects the lingering moisture from summer, bridging the gap between seasons. As the year progresses, humidity levels climb back to the high 90% range by October, emphasizing Larvik's characteristic dampness during the later months. Thus, September serves as a transitional month, preparing residents for the steadily increasing humidity and the seasonal changes that follow.

September Average Humidity in Larvik

This chart illustrates the average monthly humidity levels in Larvik, 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 Larvik is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec93%91%88%83%75%74%74%78%86%92%92%92%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Larvik

In September, Larvik experiences a moderate UV Index of 4, indicating a slight easing from the peak summer months. With a burn time of 30 minutes, it's essential to remain mindful of sun exposure as days gradually shorten. This decrease follows the intensity of July and August, which both had high UV levels, leading to significant outdoor summer activities. As the autumn approaches, the UV index starts to drop, falling back to lower levels in October. For those looking to enjoy the last rays of summer sun responsibly, keeping track of Larvik UV Index is key to safeguarding your skin while soaking in the beautiful early fall landscape.

Maximum UV Index Levels in Larvik for September

The chart shows the monthly maximum UV Index (UVI) for Larvik 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 Larvik typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec113457754211
Data source: Larvik 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 Larvik

As summer gracefully transitions into autumn, September in Larvik, Norway continues to bask in a generous supply of sunshine, boasting 290 hours of daylight. This month serves as a reminder of the warm, radiant days of summer, with sunlight gradually waning from the peak of 475 hours in July. Notably, September's substantial hours of sunshine are a striking contrast to the dim winters ahead, where dark days dominate from November to January. This shift not only emphasizes the fleeting beauty of late summer but also signals the impending chill, making the lingering sunlight all the more cherished.

Monthly Sunshine Duration in Larvik: September Highlighted

The September sunshine duration represents the total number of hours Larvik 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.
JanFebMarAprMayJunJulAugSepOctNovDec94h183h289h370h426h463h475h413h290h239h135h102h
Data source: Larvik September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Larvik During September

In Larvik, Norway, the chance of experiencing sunny weather takes a noticeable dip in September, with only a 29% likelihood of sunshine. This marks a significant decline after the more promising months of midsummer, where July and August maintain percentages around 48% and 46%, respectively. As the autumn season approaches, the clouds often gather, leading to a less favorable forecast compared to the bright days of spring and early summer, where sunny days soar to 60% in April. This trend illustrates the typical transition from the vibrant warmth of summer to the cooler and cloudier days of fall, making September a month where sun-seekers might want to temper their expectations.

Percentage of Sunny Days in September in Larvik

The chart illustrates the percentage of sunny days in Larvik 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 Larvik experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec38%41%47%60%34%45%48%46%29%31%24%28%
Data source: Larvik September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Larvik in September

In September, Larvik, Norway, experiences a notable transition in daylight duration, with the hours of sunlight decreasing to 12 hours. This marks a gradual shift from the vibrant days of summer, where daylight peaked at 18 hours in June. As autumn approaches, the gradual waning of daylight becomes evident, with September's brightness bridging the gap between the lengthy summer days and the shorter winter afternoons. Following this peak, daylight drops further, hinting at the enveloping darkness of the coming months, with just 10 hours in October and falling to 6 hours by December. This rhythm of light set against the changing seasons beautifully captures the essence of Larvik's natural cycle, inviting both reflection and seasonal appreciation.

Average Daylight Hours in Larvik for September

The chart illustrates the variation in daylight duration in Larvik throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec7h 2m9h 16m11h 52m14h 31m16h 57m18h 20m17h 35m15h 21m12h 45m10h 8m7h 41m6h 17m
Data source: Larvik daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Larvik

In September, Larvik, Norway, experiences a slight uptick in wind activity as the average wind speed reaches 4.9 m/s (11 mph). This modest increase signals a transition from the summer calm of June and July, where the winds dropped to 3.9 m/s (9 mph). As autumn approaches, the winds begin to pick up again, with September's figures reflecting the cooling weather patterns ahead. This trend foreshadows a more vigorous wind environment, as seen in October with an average speed of 6.5 m/s (14 mph). Thus, September serves as a bridge, hinting at the brisker days to come while still enjoying the lingering warmth of summer breezes.

Average September Wind Speed in Larvik

The chart displays monthly wind speed patterns in Larvik, 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.55.75.14.84.43.93.94.44.9 m/s6.55.95.5
Data source: Larvik September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Larvik Compares to Other Months

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

In September, the weather warms up with average temperatures ranging from a minimum of 7°C (44°F) to a maximum of 21°C (70°F), complemented by high humidity at 86%. This month sees a substantial amount of rainfall, totaling 128 mm (5.1 in) over approximately 13 days. In contrast, January experiences much colder temperatures, with an average ranging from -9°C (17°F) to 11°C (52°F). The precipitation is lower at 72 mm (2.8 in) spread over 9 days, and the humidity levels rise slightly to 93%. For a closer look at January weather specifics, check out Larvik weather in January.

September and February present strikingly different weather conditions. In September, temperatures range from a mild minimum of 7°C (44°F) to a pleasant maximum of 21°C (70°F), with an average of 14°C (57°F). The month experiences considerable precipitation, totaling 128 mm (5.1 in) over approximately 13 days, accompanied by high humidity levels at 86%. In contrast, February sees much colder temperatures, with a minimum of -10°C (15°F) and an average of just 1°C (34°F). Though it experiences less rainfall at 75 mm (3.0 in), precipitation occurs on about 12 days, with humidity peaking at 91%. For a deeper insight into February's weather, you can visit Larvik weather in February.

In comparing the weather of September and March, we see a stark contrast in temperatures and conditions. September enjoys milder temperatures with minimums around 7°C (44°F) and averages of 14°C (57°F), culminating in maximums reaching 21°C (70°F). It is also a relatively wet month, with 128 mm (5.1 in) of precipitation over 13 days and humidity levels at 86%. In contrast, March experiences a notable chill, with minimum temperatures plummeting to -10°C (14°F) and an average of just 3°C (37°F). While it has lower precipitation amounts at 73 mm (2.9 in) across 10 days, the humidity remains high at 88%. For more detailed insights on March weather, you can visit Larvik weather in March.

When comparing the weather in September and April, a clear contrast emerges. September tends to be much milder, with average temperatures ranging from a low of 7°C (44°F) to a high of 21°C (70°F), while April experiences cooler conditions, with temperatures ranging from -5°C (24°F) to 16°C (61°F). Precipitation also differs significantly; September sees around 128 mm (5.1 in) of rainfall over 13 days, compared to April's much lighter 34 mm (1.3 in) over just 5 days. Additionally, both months exhibit high humidity, but September is slightly more humid at 86%, compared to April's 83%. For those seeking a detailed glimpse into April's weather patterns, visit Larvik weather in April.

The weather in September tends to be milder compared to May, with average temperatures ranging from a minimum of 7°C (44°F) to a maximum of 21°C (70°F), while May sees temperatures from a minimum of 3°C (37°F) to a maximum of 25°C (77°F). Additionally, September experiences higher humidity at 86% and significantly more precipitation, with 128 mm (5.1 in) over 13 days, compared to May's 70 mm (2.8 in) across 9 days. Consequently, September feels much wetter and cooler, while May offers a drier and slightly warmer ambiance. For a more detailed look at May weather, you can visit Larvik weather in May.

In September, the weather tends to be cooler and wetter compared to June. The average temperature in September is around 14°C (57°F), with a maximum of 21°C (70°F) and a minimum of 7°C (44°F). This month also experiences significant rainfall, with 128 mm (5.1 in) over 13 days and higher humidity levels at 86%. In contrast, June offers warmer conditions with an average temperature of 16°C (61°F), peaking at 25°C (78°F) and dropping to a minimum of 8°C (46°F). Additionally, June sees less precipitation, totaling 81 mm (3.2 in) across 9 days, and generally lower humidity at 74%. For more specific details, check out Larvik weather in June.

September and July exhibit notable differences in weather patterns. In September, temperatures cool down, with minimums averaging 7°C (44°F) and maximums reaching 21°C (70°F), resulting in an average temperature of 14°C (57°F). In contrast, July remains warmer, with a minimum temperature of 11°C (52°F) and a maximum of 26°C (80°F), leading to a higher average of 18°C (64°F). Additionally, September experiences significantly more rainfall, totaling 128 mm (5.1 inches) over 13 days, compared to July’s 84 mm (3.3 inches) over 9 days. Humidity also rises in September, averaging 86%, compared to July's 74%. For more detailed insights, you can check Larvik weather in July.

In comparing the weather of September and August, we see a notable shift in temperature and precipitation patterns. September features cooler temperatures, with averages ranging from a minimum of 7°C (44°F) to a maximum of 21°C (70°F), while August typically enjoys milder conditions, with a minimum of 11°C (51°F) and a maximum of 24°C (75°F). Additionally, September experiences more rainfall, accumulating 128 mm (5.1 in) over 13 days, compared to August's 81 mm (3.2 in) over 11 days. Humidity is also higher in September at 86%, compared to 78% in August, reflecting the transition to autumn. For more details on August weather, you can check Larvik weather in August.

September weather is generally milder, featuring temperatures ranging from a minimum of 7°C (44°F) to a maximum of 21°C (70°F), with an average of 14°C (57°F). It experiences 128 mm (5.1 in) of precipitation over 13 days and maintains a humidity level of 86%. In contrast, October brings cooler temperatures, with a minimum of 1°C (34°F), an average of 10°C (50°F), and a maximum of 16°C (61°F). Precipitation increases slightly to 144 mm (5.7 in) across 15 days, and humidity rises to 92%. For a detailed look at October weather patterns, you can visit Larvik weather in October.

In comparing the weather in September and November, we see a notable drop in temperatures. September typically experiences milder conditions, with average temperatures ranging from a minimum of 7°C (44°F) to a maximum of 21°C (70°F), while November presents a chillier environment, with average temperatures between -3°C (26°F) and 14°C (58°F). Although both months receive substantial rainfall, September has a slightly higher total precipitation of 128 mm (5.1 in) over 13 days compared to November's 122 mm (4.8 in) over 16 days. Additionally, humidity levels are greater in November at 92%, compared to September's 86%, contributing to the cooler, more damp sensation in the air. For a detailed look at November's climate, you can visit Larvik weather in November.

In September, the weather features milder temperatures, with a minimum of 7°C (44°F) and an average of 14°C (57°F), peaking at 21°C (70°F). The month experiences around 128 mm (5.1 in) of precipitation spread across 13 days, accompanied by relatively high humidity levels at 86%. In contrast, December ushers in much colder conditions, where temperatures drop significantly, with a minimum of -5°C (22°F) and an average of 3°C (37°F), reaching a maximum of 11°C (52°F). Precipitation levels are similar to September, at 129 mm (5.1 in), but it occurs over 17 days, with humidity increasing slightly to 92%. For more detailed information on December weather, you can check Larvik weather in December.

Compare Larvik's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Larvik

As summer gives way to autumn, September in Larvik presents a unique climate blend that contrasts with the months preceding it. The temperature sees a notable dip, transitioning from the warmth of summer to cooler averages, while the humidity climbs, offering a refreshing yet crisp atmosphere. This month is characterized by a greater chance of rainfall, with precipitation occurring on more days than in the drier summer, making it essential to prepare for those unexpected showers. The vibrant hues of the changing foliage, coupled with cooler breezes, create a picturesque backdrop that highlights September's distinct charm. For a deeper dive into the weather dynamics of Larvik, check out Larvik Climate.