Last updated: August 27, 2025
In September, Tromsø, Norway experiences a thrilling transition into autumn, with temperatures ranging from a maximum of 20°C (69°F) to a minimum of -1°C (30°F). The average temperature settles at a cool 8°C (47°F), capturing the crispness of the season. This month is also characterized by a notable precipitation level, totaling 132 mm (5.2 in) over approximately 17 days, contributing to the region's lush landscapes. With an average humidity of 91%, the air feels refreshing yet invigorating, making September a unique time to explore the breathtaking natural beauty of Tromsø.
In September, Tromsø begins its transition from the warmth of summer to the chill of autumn, with temperatures showcasing a distinct shift. The month starts with a minimum of around -1°C (30°F) and an average hovering at 8°C (47°F), gradually giving way to the impending colder months. Daytime highs can reach up to 20°C (69°F), offering a pleasant taste of late summer for outdoor enthusiasts. This progressive drop in temperature marks a notable change from the balmy heights of July and August, while still holding a glimpse of warmth, inviting visitors to experience the ethereal beauty of the Nordic landscape as it begins to don its autumn cloak. As the month closes, the air turns crisper, underscoring the onset of the long winter ahead.
In September, Tromsø experiences a notable uptick in precipitation, with 132 mm (5.2 in) of rain falling over the month. This marks a continuation of the wet summer trend, where August recorded 128 mm. The rain falls across 17 days, maintaining a steady rhythm of moisture that characterizes the autumn transition. Interestingly, this pattern contrasts with the preceding month of August and the subsequent October, where precipitation drops to 87 mm (3.4 in). Overall, September serves as a bridge, blending the lingering summer rainfall with the drier conditions that lie ahead, showcasing Tromsø's dynamic climate as it shifts toward the colder months.
In September, Tromsø experiences a notable shift as humidity levels settle at 91%, marking a return to higher moisture content in the air. Following the slightly elevated levels of August, where humidity reached 88%, September's climate signals the onset of autumn. This month displays a gradual counterpoint to the drier spring and summer months, which hovered around the 80% range from May to July. As temperatures cool and days shorten, the rise in humidity serves as a reminder of the winter climate to come, where humidity levels consistently remain high throughout the fall and winter months, often reaching 94% by December. This trend highlights Tromsø's unique and captivating blend of crisp air and lingering moisture, characteristic of its northern charm.
In September, Tromso, Norway experiences a UV Index of 2, placing it in the low exposure category. This means that while the sun's rays become gradually milder as autumn approaches, sunburn can still occur if you're outside for too long—approximately 45 minutes is the burn time for fair-skinned individuals. Following a season of moderate UV levels peaking at 5 in July, the trend shows a gentle decline as daylight hours shorten. The shift to lower UV levels reminds residents and visitors alike to enjoy the crisp autumn air without neglecting sun safety. For more details on UV exposure in Tromso, check out the Tromso UV Index.
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As summer gracefully gives way to autumn, September in Tromsø still basks in a commendable 263 hours of sunshine. This marks a gentle decline from the sun-drenched days of July and August, which boasted over 450 hours, showcasing the region's vibrant midnight sun. The gradual drop in daylight hours begins to set the stage for the winter months, with October plunging further to just 163 hours. However, September remains a bridge between the lively summer skies and the impending winter gloom, inviting visitors to enjoy the lingering warmth and brilliant sunsets before the long, sunless months arrive.
In Tromsø, Norway, the likelihood of sunny weather sees a noticeable dip during the summer months, with July and August recording the lowest chances at 16% and 14% respectively. As September rolls in, the chance of sunshine improves slightly to 21%, marking a gentle rebound as the region transitions into autumn. While this figure remains modest compared to the winter months like January and December, which boast higher percentages of 33% and 34% respectively, September offers a unique window for enjoying the stunning landscapes before the colder temperatures set in. This month serves as a reminder that while summer may retreat, the beauty of Tromsø is ever-present, with even a little sunshine being a cherished sight.
As September arrives in Tromsø, Norway, the lingering brightness of summer begins to wane, transitioning from the vibrant 24 hours of daylight in June to a more subdued 13 hours this month. This gradual decline marks a significant shift from the sun-soaked days of early summer, reflecting the onset of autumn. After the long, continuous exposure to light during the summer months, September still offers a refreshing balance, allowing residents to savor the changing hues of the landscape before the daylight dips further to 8 hours in October. This trend illustrates the unique rhythm of life in the Arctic, where daylight transforms dramatically throughout the year, creating a captivating natural spectacle.
As September settles in Tromsø, the wind begins to whisper a gentle retreat, with average speeds clocking in at 2.3 m/s (5 mph). This marks the lowest level for the year, following a summer characterized by a slight uptick in breezy days, peaking at 2.9 m/s (7 mph) in both July and March. As autumn approaches, the winds tend to calm, transitioning from the mild gusts of summer to a softer caress, signaling a shift towards the winter months. Overall, the gradual dip in speed throughout the later summer months hints at the serene yet invigorating atmosphere that characterizes Tromsø’s fall season, inviting locals and visitors alike to appreciate the quiet beauty of the landscape as it prepares for the colder days ahead.
Weather in Tromso varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Tromso, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January in Tromsø present stark contrasts in weather conditions. In September, temperatures range from a chilly -1°C (30°F) at night to a mild 20°C (69°F) during the day, with an average of 8°C (47°F). This month sees significant rainfall, totaling 132 mm (5.2 inches) over 17 days and high humidity levels at 91%. In contrast, January is much colder, with temperatures plummeting as low as -23°C (-9°F) and averaging -5°C (23°F), peaking at just 7°C (45°F). Although it experiences less precipitation than September, totaling 97 mm (3.8 inches) over 13 days, January retains a high humidity of 95%. For a detailed look at January weather, you can refer to Tromso weather in January.
September and February present striking contrasts in weather. In September, temperatures range from a chilly -1°C (30°F) to a comfortable max of 20°C (69°F), with an average of 8°C (47°F). However, this month also experiences significant precipitation, with 132 mm (5.2 in) of rain over 17 days, coupled with a high humidity level of 91%. In contrast, February is much colder, with temperatures dipping as low as -21°C (-5°F) and reaching a maximum of only 7°C (44°F), averaging -6°C (21°F). The month sees slightly less precipitation at 99 mm (3.9 in) over 16 days, yet the humidity remains high at 93%. For a detailed overview of February's weather, you can visit Tromso weather in February.
When comparing September and March weather in Tromsø, there are notable differences in temperature and precipitation patterns. September enjoys milder temperatures with an average of 8°C (47°F), while March is much colder, averaging -3°C (26°F) with maximum temperatures reaching only 9°C (48°F). Both months experience high humidity levels of 91%, contributing to a damp feel in the air. In terms of precipitation, September receives around 132 mm (5.2 in) over 17 days, while March is slightly wetter, with 139 mm (5.5 in) over 19 days. For those interested in details about March weather specifically, please visit Tromso weather in March.
When comparing the weather in September and April, we can see some notable differences. September features milder temperatures, with an average of 8°C (47°F), while April is significantly colder, averaging around 0°C (33°F). The minimum temperature in September dips to -1°C (30°F), compared to April's chillier low of -14°C (7°F). Both months experience a similar amount of precipitation, with September receiving 132 mm (5.2 in) and April slightly less at 119 mm (4.7 in), although both months have about 17 days of rain. Humidity is high in both months, with September at 91% and April just a touch lower at 89%. For more detailed insights, you can explore Tromso weather in April.
In comparing the weather of September and May, September generally presents slightly milder conditions with an average temperature of 8°C (47°F) compared to May's average of 5°C (41°F). While September can reach a maximum of 20°C (69°F), May often warms up to 21°C (70°F) on its warmest days. Precipitation levels are fairly close, with September receiving 132 mm (5.2 in) over 17 days, while May sees 98 mm (3.9 in) also across 17 days. Humidity is notably higher in September at 91%, compared to May's 83%. For a detailed look at May's weather, you can visit Tromso weather in May.
When comparing the weather in September and June, noticeable differences emerge in both temperature and humidity. September experiences cooler temperatures with a minimum of -1°C (30°F) and an average of 8°C (47°F), while June is slightly warmer, starting at a minimum of 1°C (34°F) and reaching an average of 9°C (49°F). The maximum temperatures also reflect this trend, with September peaking at 20°C (69°F) compared to June's 23°C (73°F). Although precipitation levels are quite similar, with September receiving 132 mm (5.2 in) across 17 days and June slightly lower at 130 mm (5.1 in) over 18 days, September is notably more humid at 91%, contrasting with June's 84% humidity. For more detailed insights on June weather, visit Tromso weather in June.
In comparing the weather between September and July, we find notable differences in temperature and precipitation patterns. September experiences cooler conditions, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 20°C (69°F), while July is significantly warmer, with temperatures from 5°C (41°F) to 28°C (82°F). Precipitation is more frequent in September, totaling 132 mm (5.2 in) over 17 days, compared to July's 100 mm (4.0 in) over 14 days. Additionally, September tends to be more humid, with levels reaching 91%, while July maintains a lower humidity of 85%. For more detailed information, visit Tromso weather in July.
In comparing the weather patterns of August and September, September showcases a noticeable drop in temperatures, with a minimum of -1°C (30°F) compared to August's 4°C (39°F). The average temperature in September is also lower at 8°C (47°F), significantly contrasting with August's more pleasant 11°C (53°F). The monthly maximum temperature in September peaks at 20°C (69°F), while August reaches a warmer maximum of 27°C (80°F). Both months experience similar precipitation levels, with September recording 132 mm (5.2 in) over 17 days, slightly more than August's 128 mm (5.0 in) over 19 days. Humidity remains high in both months, but September is slightly more humid at 91% compared to August's 88%. For a detailed look at weather conditions in August, you can check Tromso weather in August.
In September, the weather in Tromsø showcases a relatively mild temperature range, with a minimum of -1°C (30°F) and a maximum of 20°C (69°F), along with an average of 8°C (47°F). The month is also characterized by significant precipitation, totaling 132 mm (5.2 in) over 17 days, and a humidity level of 91%.
In contrast, October experiences a drop in both temperature and overall warmth, with a minimum of -11°C (13°F), an average of 3°C (37°F), and a maximum of 16°C (60°F). Although the rainfall decreases to 87 mm (3.4 in) across 16 days, the humidity remains high at 92%. For more detailed insights about the conditions in this month, you can refer to Tromso weather in October.
In September, the weather is relatively mild with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 20°C (69°F) and an average of 8°C (47°F). This month experiences considerable precipitation, with 132 mm (5.2 in) over 17 days, and a high humidity level of 91%. In stark contrast, November brings much colder conditions, characterized by temperatures that can drop to a minimum of -22°C (-7°F) and an average of -1°C (31°F), rising only to a maximum of 10°C (50°F). Despite slightly lower overall precipitation at 113 mm (4.5 in) over 19 days, the humidity remains high at 92%. For more details, visit Tromso weather in November.
September and December present strikingly different weather conditions. In September, temperatures range from a chilly -1°C (30°F) at night to a pleasant maximum of 20°C (69°F) during the day, offering an average of 8°C (47°F). The month sees considerable rainfall, with 132 mm (5.2 in) spread over 17 days, and high humidity levels at 91%. In contrast, December brings much colder temperatures, with nighttime lows plummeting to -21°C (-5°F) and daytime highs reaching only 8°C (46°F), resulting in an average of -4°C (25°F). Precipitation decreases to 80 mm (3.1 in) over 15 days, while humidity remains high at 94%. For a more detailed look at what to expect, you can check out Tromso weather in December.
As September unfolds in Tromsø, it presents a notable shift from the summer's warmth, transitioning to cooler temperatures and increased precipitation. With an average temperature hovering around 8°C, residents and visitors alike prepare for the briskness of autumn, where chilly nights can dip close to freezing. This month also witnesses frequent rain, affecting nearly half the days, and with humidity levels peaking at 91%, the air feels distinctly crisp and damp. While the lush greenery of summer begins to fade, September offers a unique charm, as the landscape starts to transform in preparation for winter. To learn more about seasonal changes and the overall weather trends in the area, visit Tromso Climate.