Last updated: August 27, 2025
In Norrtälje, Sweden, September offers a mild transition into autumn, with maximum temperatures reaching a comfortable 22°C (73°F) and an average of 13°C (55°F). The weather showcases a cooler side as temperatures dip to a minimum of 2°C (35°F). Rain is a notable feature this month, with 47 mm (1.8 in) of precipitation spread over 9 days, contributing to a high humidity level of 85%. This blend of warm days and refreshing rains creates a unique, invigorating atmosphere, ideal for enjoying the natural beauty of this charming Swedish town.
In Norrtälje, Sweden, September marks a significant transition as summer gives way to autumn. With minimum temperatures gently dropping to 2°C (35°F), the month brings a refreshing coolness compared to the warmer months of July and August. The average temperature settles around 13°C (55°F), inviting sweater weather while still offering pleasant days that can reach a comfortable 22°C (73°F) at its peak. This notable shift reflects the broader seasonal trend where the vibrancy of summer is exchanged for the crisp, colorful charm of fall, creating a picturesque backdrop for outdoor strolls amid changing foliage.
September in Norrtälje, Sweden, brings a moderate precipitation total of 47 mm (1.8 in), providing a gentle transition from the more dramatic rainfall of late summer. With 9 rainy days throughout the month, this period captures the essence of autumn, where the lush greenery begins to soften. Interestingly, September's precipitation is lower than the preceding months of July and August, which saw 61 mm and 62 mm respectively, signaling a shift as the weather cools. However, it does lay the groundwork for October's typically wetter patterns, often featuring increased rainfall. Overall, September serves as a balanced respite before the autumn deluge, balancing just enough rain to nourish the landscape while hinting at the season's turning.
In September, Norrtälje, Sweden, experiences a noticeable shift in humidity, averaging around 85%. This marks a gentle rise from the drier summer months of July and August, which saw levels drop to 74% and 77%, respectively. As the warm days fade and autumn approaches, the environment begins to retain a bit more moisture, aligning humidity levels closer to what is typical in earlier months, with October returning to 89%. This trend highlights the seasonal transition, as the crisp air of September prepares the way for the more humid days of fall, reminiscent of the wetter conditions experienced in winter months like January and November. Overall, the change in September reflects a dynamic interplay between seasonal warmth and the impending chill of winter, creating a unique atmospheric character for Norrtälje.
In September, Norrtälje, Sweden, experiences a moderate UV Index of 4, indicating the need for some sun protection during outdoor activities. As the summer sun wanes, this figure represents a slight decrease from the high index values of 7 recorded in July and moderate levels of 5 in August. With a recommended burn time of 30 minutes, it's a reminder that while the season is shifting, the sun's rays can still be strong. As we transition further into autumn, the UV Index will continue to drop, showcasing the changing landscape of seasonal sun exposure. For more detailed insights, visit Norrtaelje UV Index.
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September in Norrtälje, Sweden, is a picturesque transition between summer's radiant embrace and autumn's crisp arrival, boasting 314 hours of sunlight. This month experiences a noticeable decline in daylight compared to the sun-drenched days of July and June, which record high peaks of 490 and 483 hours respectively. However, September still shines brighter than the gloomy months ahead, such as October with only 217 hours and November’s mere 136 hours. This gradual decrease not only signifies the changing season but also offers residents a chance to savor the last warm rays of sunshine before winter casts its long shadows.
In Norrtälje, Sweden, September ushers in the early hints of autumn, but the likelihood of sunny weather dips to 27%, a notable decrease from the vibrant summer months. Following the peak of July's 57% sunshine, the cloud cover begins to creep in, casting a shadow on the once bright skies. While this month still holds the charm of lingering sunny days, it's a stark contrast to the sunnier months of June and July. As the days shorten and temperatures cool, residents and visitors alike can expect a mix of sun and occasional clouds, making each sunny moment all the more precious.
In September, Norrtälje experiences a notable transition as daylight hours begin to wane, offering about 12 hours of sunlight. Following the vibrant summer months, when daylight peaked at 18 hours in June, the days gradually shorten, reflecting the shift towards autumn. This month serves as a gentle reminder of the fading warmth, with daylight declining from 15 hours in August. As the year progresses into October, daylight further diminishes to 10 hours, showcasing a clear trend of decreasing sunlight that mirrors the arrival of cooler weather. Embracing the early dusk, September invites both reflection and preparation for the enchanting changes autumn brings.
As September unfolds in Norrtälje, Sweden, the average wind speed reaches a gentle 4.2 m/s (9 mph), slightly higher than the preceding summer months. This subtle increase reflects a gradual transition as autumn approaches, following the soft breezes of July and August, which registered at 3.4 m/s (8 mph) and 4.1 m/s (9 mph), respectively. Interestingly, this month serves as a bridge to the more blustery conditions expected in October, when winds typically pick up to 5.3 m/s (12 mph). Overall, September's winds signal a shift, preparing the landscape for the crisper air and vibrant colors of fall, while maintaining a characteristic calm that encourages outdoor enjoyment.
Weather in Norrtaelje varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Norrtaelje, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is relatively mild, with temperatures ranging from a minimum of 2°C (35°F) to a maximum of 22°C (73°F) and an average of 13°C (55°F). This month also sees about 47 mm (1.8 in) of precipitation over approximately 9 days, with humidity levels around 85%. In contrast, January experiences much colder conditions, with temperatures dropping to as low as -14°C (7°F), peaking at 9°C (49°F) and averaging 0°C (32°F). Precipitation is slightly lower at 39 mm (1.5 in) over about 10 days, but humidity remains high at 90%. For more detailed information, you can refer to Norrtaelje weather in January.
In comparing the weather of September to February, one can see significant contrasts. September experiences milder temperatures, with a minimum of 2°C (35°F) and an average of 13°C (55°F), reaching up to a maximum of 22°C (73°F). The month also sees a relatively higher precipitation level of 47 mm (1.8 in) over 9 days, accompanied by humidity at 85%. In stark contrast, February is much colder, with temperatures ranging from a minimum of -14°C (7°F) to a maximum of 9°C (49°F) and an average of -1°C (31°F). Although February has slightly less precipitation at 35 mm (1.4 in), it maintains a similar number of rainy days with precipitation spread over 9 days, and a higher humidity level of 88%. For more detailed information, you can visit Norrtaelje weather in February.
In comparing the weather of September and March, we see a notable contrast in temperatures and general conditions. September boasts a milder climate, with average temperatures ranging from a minimum of 2°C (35°F) to a maximum of 22°C (73°F), accompanied by 47 mm (1.8 in) of precipitation over about 9 days. The humidity is relatively high at 85%, making it feel quite moist.
In contrast, March is significantly colder, with temperatures dipping to a minimum of -13°C (9°F) and only reaching a maximum of 17°C (62°F). It experiences slightly less precipitation at 40 mm (1.6 in) across roughly 7 days, but with higher humidity at 89%, the air feels even chillier. For more details, check out Norrtaelje weather in March.
When comparing the weather of September and April, significant differences in temperature and precipitation patterns are evident. September typically features a milder range, with average temperatures around 13°C (55°F), peaking at 22°C (73°F), while April remains chillier, averaging 4°C (40°F) with a low of -10°C (15°F). Despite the warmth of September, it experiences slightly higher precipitation, totaling 47 mm (1.8 in) over about 9 days, compared to April's 26 mm (1.0 in) over 7 days. Both months share a high humidity level of 85%, giving a similar feeling of dampness, but the overall experience of April is marked by its lingering cold, making the transition into spring quite distinct. For more detailed insights, check out Norrtaelje weather in April.
When comparing the weather in September and May, we find notable differences in temperature and humidity. September tends to be milder, with average temperatures ranging from a minimum of 2°C (35°F) to a maximum of 22°C (73°F), while May shows a broader temperature range with a minimum of -2°C (29°F) and a maximum of 25°C (78°F). Despite both months experiencing similar levels of precipitation and rainy days—47 mm (1.8 in) in September and 48 mm (1.9 in) in May—September's higher humidity at 85% contrasts with May's relatively lower humidity of 77%. For more specific insights, you can explore Norrtaelje weather in May.
September and June exhibit notably different weather patterns, reflecting the transition from summer to autumn. In September, temperatures range from a chilly minimum of 2°C (35°F) to a comfortable maximum of 22°C (73°F), with an average of 13°C (55°F). The month is characterized by 47 mm (1.8 in) of precipitation over approximately 9 days, and a higher humidity of 85%. Conversely, June offers warmer temperatures, seeing a minimum of 5°C (41°F) and a maximum reaching 28°C (82°F), with an average sitting at 16°C (60°F). Precipitation in June is slightly lower at 42 mm (1.7 in) over about 7 days, coupled with a more moderate humidity of 76%. For more details on the conditions in June, you can check Norrtaelje weather in June.
In comparing the weather of September and July, it's evident that July is significantly warmer. With minimum temperatures averaging 8°C (47°F) and reaching highs of 30°C (86°F), July is characterized by a more temperate climate. In contrast, September experiences colder conditions, with minimum temperatures dropping to 2°C (35°F) and a maximum of only 22°C (73°F). Additionally, July sees less rainfall, accumulating 61 mm (2.4 in) over 10 days, while September has 47 mm (1.8 in) over 9 days. Humidity levels are also lower in July at 74%, compared to September's 85%. For further details, you can check out Norrtaelje weather in July.
In comparing the weather of September to that of August, September generally displays cooler temperatures with a minimum of 2°C (35°F) and an average of 13°C (55°F), contrasting with August's milder conditions, where temperatures start at a minimum of 6°C (44°F) and reach an average of 17°C (63°F). The maximum temperatures in September peak at 22°C (73°F), which is significantly lower than August's high of 28°C (82°F). Additionally, September tends to be wetter, receiving 47 mm (1.8 in) of precipitation over 9 days, while August experiences 62 mm (2.4 in) over 12 days. The humidity in September is higher at 85% compared to August's 77%, making the early fall feel more damp. For more details on the weather in August, you can refer to Norrtaelje weather in August.
September and October showcase a notable shift in weather conditions. In September, temperatures range from a minimum of 2°C (35°F) to a pleasant maximum of 22°C (73°F), with an average of 13°C (55°F). The month experiences 47 mm (1.8 in) of precipitation over 9 days and maintains a humidity level of 85%. In contrast, October sees a drop in temperatures, with lows of 0°C (32°F) and highs peaking at 17°C (63°F), averaging around 8°C (47°F). Additionally, October is wetter, receiving 72 mm (2.8 in) of rain across 13 days, and the humidity rises slightly to 89%. For more detailed information, check out Norrtaelje weather in October.
In September, the weather is typically milder, with average temperatures ranging from a low of 2°C (35°F) to a comfortable high of 22°C (73°F). The month experiences moderate precipitation of 47 mm (1.8 in) over about 9 days, accompanied by a relatively high humidity level of 85%. In contrast, November sees much colder conditions, with average temperatures dropping to a minimum of -8°C (19°F) and a maximum of 14°C (57°F). Precipitation levels are slightly lower at 44 mm (1.7 in), though it rains on about 10 days, and the humidity rises to 90%. For more details on November weather, visit Norrtaelje weather in November.
In September, temperatures are relatively mild with a minimum of 2°C (35°F) and an average of 13°C (55°F), peaking at 22°C (73°F). The month experiences moderate rainfall of 47 mm (1.8 in) over about 9 days, accompanied by a humidity level of 85%. In contrast, December brings significantly colder weather, with temperatures dropping to a minimum of -12°C (11°F) and an average high of just 9°C (49°F). Precipitation increases to 65 mm (2.6 in) over 14 days, with humidity slightly higher at 87%. For more insights on the chilly conditions, visit Norrtaelje weather in December.
As September unfolds in Norrtälje, the transition from the warmth of summer to the cool touch of autumn becomes evident. With temperatures averaging around 13°C (55°F) and maximum highs reaching 22°C (73°F) during the day, the air carries a refreshing chill, especially in the early mornings. This month also sees an uptick in precipitation, with about 47 mm spread over nine days, which contributes to the lush greenery that nurtures the landscape. The humidity lingers at a notable 85%, creating a humid atmosphere that feels distinctly different from the drier summer months. As summer fades, September invites a tranquil shift, making it a unique time to experience the beauty of Norrtälje. For a deeper dive into the area's weather patterns, visit Norrtaelje Climate.