Last updated: August 21, 2025
In September, the weather in Viljandi, Estonia showcases a striking transition between the warmth of summer and the chill of autumn. With maximum temperatures reaching 26°C (79°F) and an average of 12°C (55°F), the month offers a pleasant mix of warmth during the day while nights can dip to a minimum of -2°C (28°F). Rainfall is a notable feature, with 75 mm (3.0 in) of precipitation spread over 14 days, contributing to the 89% humidity that envelops the region. This blend of temperature and moisture creates a vibrant environment, perfect for experiencing the serene beauty of Viljandi as it begins to embrace the fall season.
In September, Viljandi, Estonia, experiences the gentle shift of summer into autumn, with temperatures showing a notable range. The month begins with minimums around -2°C (28°F), providing a crisp start, while daytime highs can reach up to 26°C (79°F), creating pleasant, warm afternoons. This average temperature settles at a comfortable 12°C (55°F), marking a transition from the warmth of summer to the cooler embrace of fall. As days shorten and the leaves begin to change, September is a delightful time for outdoor activities, showcasing the beauty of Viljandi's landscape in a spectrum of colors.
In September, Viljandi, Estonia, experiences a notable shift in its precipitation patterns as summer gives way to autumn. With 75 mm (3.0 in) of rain spread over an average of 14 days, this month marks a peak in rainfall frequency, surpassing the drier months earlier in the year. The increase in precipitation aligns with the transition into cooler weather, but it's also a slight dip compared to the wetter August, which recorded 99 mm (3.9 in). This consistent pattern of rainfall in September serves as a reminder of the lush landscapes that define this charming town as it prepares for the crispness of fall. Overall, while the month brings more rain-drenched days, it does so with a rhythm that echoes the season's change.
In September, Viljandi, Estonia experiences a noticeable uptick in humidity, with levels rising to 89%. This increase follows the trend of the summer months, where humidity hovered in the low to mid-80s. August's 84% sets the stage for September's rise, indicating a transition as the region shifts from the warmer summer climate toward the cooler fall season. Despite this uptick, September remains less humid than the peak winter months, January and February, which consistently hold near 93%. This gradual decrease establishes a pattern where humidity begins to stabilize as autumn progresses, setting the scene for crisp, refreshing days ahead.
As the summer fades, September in Viljandi, Estonia welcomes a moderate UV Index of 4, indicating a shift from the high levels experienced in the summer months. While the sun may be less intense than in July and August—both hitting a high of 7—September still calls for mindful sun exposure. With a burn time of 30 minutes, it's advisable to enjoy the pleasant autumn days while taking protective measures against UV rays. This month's UV Index highlights a gradual transition towards the lower levels of autumn, where the index drops to 2 in October and 1 by November. For more detailed information, visit Viljandi UV Index.
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In Viljandi, Estonia, September marks a delightful transition as summer's warmth begins to wane, offering 300 hours of sunshine. This abundance of daylight encourages lingering outdoor activities, painting the town in soft golden hues. The sunshine hours reflect a steady decline from June's peak of 467 hours, yet still comfortably surpass the gloom of the upcoming months. As autumn settles in, a gradual decrease can be observed, with sunlight diminishing significantly by October. This trend highlights how September acts as a bridge, wrapping the lingering joys of summer in a warm embrace before the crispness of autumn fully takes hold.
In September, Viljandi, Estonia experiences a 27% chance of sunny weather, marking a subtle decline from the vibrant summer months. The increasing likelihood of sunlight peaks during June and July, reaching over 51% and 54%, respectively, providing residents and visitors with ample opportunities to enjoy the outdoors. As the warmth of summer transitions into early autumn, the chances of sunshine gradually taper off, reflecting the shifting seasons. While September still offers a fair share of sunny days compared to the colder months ahead, it hints at the cooler, more overcast days to come, as summer's glow gives way to autumn's embrace.
As summer fades and autumn approaches in Viljandi, Estonia, September marks a notable transition in daylight duration. With approximately 12 hours of daylight, the month stands as a bridge between the lengthy, sun-soaked days of summer, where June boasts an impressive 18 hours, and the shorter, dimmer days of October. After July’s gradual decline to 17 hours, August sees a still-generous 15 hours, yet September hints at the seasonal shift to the darker months ahead. This gradual decrease not only reflects the changing seasons but also invites residents to embrace the vibrant hues of fall, making September a delightful time in Viljandi as the landscape transforms beneath the softening light.
As September arrives in Viljandi, Estonia, the breeze begins to pick up, with an average wind speed of 4.2 m/s (9 mph), mirroring the gentle winds of August. This month serves as a transitional period, maintaining the invigorating winds that have characterized the late summer while hinting at the more robust gusts to come in October, when the wind speed increases to 5.0 m/s (11 mph). It's interesting to note how the wind speeds fluctuate throughout the year, starting from a calm 2.8 m/s (6 mph) in June, then gradually building up through the summer months, peaking in October. September's winds encapsulate a feeling of change, marking the shift from the warmth of summer into the cool embrace of autumn, creating a perfect backdrop for leisurely strolls by the picturesque lakes of Viljandi.
Weather in Viljandi varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Viljandi, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January in Viljandi present stark contrasts in weather. In September, temperatures range from a mild -2°C (28°F) at night to a comfortable high of 26°C (79°F) during the day, with an average of 12°C (55°F). The month experiences relatively high humidity at 89% and sees about 75 mm (3.0 in) of precipitation over 14 days. In contrast, January is much colder, with temperatures plunging to a minimum of -21°C (-6°F) and a maximum of just 8°C (46°F), averaging -2°C (28°F). Despite receiving less precipitation at 38 mm (1.5 in) over 10 days, January's humidity is slightly higher at 95%. For more details, you can check Viljandi weather in January.
September and February present strikingly contrasting weather patterns. In September, temperatures range from a minimum of -2°C (28°F) to a pleasant average of 12°C (55°F), peaking at a maximum of 26°C (79°F). With 75 mm (3.0 inches) of precipitation over about 14 days and humidity at 89%, September often feels balmy. In comparison, February chills the air with temperatures dipping as low as -24°C (-11°F), averaging -3°C (27°F) and reaching a maximum of just 8°C (47°F). Precipitation decreases to 47 mm (1.9 inches) over 10 days, and humidity stays slightly higher at 93%. For more details about the weather during this cold month, check out Viljandi weather in February.
In comparing the weather of September and March, a notable shift in temperatures and conditions emerges. September experiences a more moderate climate, with average temperatures ranging from a minimum of -2°C (28°F) to a pleasant maximum of 26°C (79°F), along with higher precipitation levels at 75 mm (3.0 in) over 14 days and humidity at 89%. In contrast, March presents a stark chill, with temperatures dropping significantly, from a minimum of -23°C (-9°F) to a maximum of only 13°C (55°F). Precipitation in March is lower, totaling 53 mm (2.1 in) over 12 days, albeit with similar humidity levels at 90%. For more detailed insights, check out Viljandi weather in March.
When comparing the weather in September and April, we can observe notable differences in temperature and precipitation. September boasts a milder average temperature of 12°C (55°F) with daytime highs reaching up to 26°C (79°F), making it more comfortable for outdoor activities. In contrast, April's cooler average of 5°C (42°F) features lower maximum temperatures of 22°C (73°F) and a chilling minimum of -8°C (18°F). Both months experience similar humidity levels, with September at 89% and April at 87%. Additionally, while September records 75 mm (3.0 in) of rain over 14 days, April has less precipitation at 51 mm (2.0 in) over 11 days, suggesting that April may be slightly drier overall. For more detailed information, you can visit Viljandi weather in April.
September and May present contrasting weather patterns, each with its distinct characteristics. In September, temperatures range from a minimum of -2°C (28°F) to a maximum of 26°C (79°F), with an average of 12°C (55°F). The month sees about 75 mm (3.0 in) of precipitation over 14 days, coupled with high humidity at 89%. In comparison, May features slightly cooler conditions, with temperatures ranging from -5°C (24°F) to a peak of 28°C (82°F) and an average of 11°C (52°F). Precipitation in May is lower, at 51 mm (2.0 in) over 10 days, and humidity is notably less, at 73%. For a detailed look at May weather, you can visit Viljandi weather in May.
September and June present contrasting weather patterns. In September, the temperatures range from a chilly minimum of -2°C (28°F) to a comfortable maximum of 26°C (79°F), with an average of 12°C (55°F). The month experiences 75 mm (3.0 in) of precipitation over 14 days, accompanied by high humidity at 89%. In contrast, June enjoys milder temperatures, with lows of 3°C (38°F) and highs reaching up to 31°C (88°F), averaging 17°C (62°F). June also totals 76 mm (3.0 in) of rainfall but over just 12 days, and the humidity is lower at 77%. For a closer look at the weather specifics, check out Viljandi weather in June.
When comparing the weather in September to July, several key differences emerge. September experiences cooler temperatures, with a minimum of -2°C (28°F) and an average of 12°C (55°F), significantly lower than July's minimum of 5°C (42°F) and average of 18°C (64°F). While July enjoys warmer days, peaking at 31°C (88°F), September's maximum temperature reaches a more moderate 26°C (79°F). Additionally, September sees slightly more precipitation, with 75 mm (3.0 in) over 14 days, compared to July's 82 mm (3.2 in) spread over 12 days, although July has a lower humidity level at 80% versus September's 89%. For more detailed insights into July weather, visit Viljandi weather in July.
In comparing the weather conditions of September and August, it’s evident that September experiences cooler temperatures, with a minimum of -2°C (28°F) and an average of 12°C (55°F), whereas August has milder temperatures ranging from a minimum of 5°C (42°F) to an average of 17°C (62°F). The maximum temperatures in August reach up to 31°C (87°F), significantly warmer than September's maximum of 26°C (79°F). Precipitation levels are slightly lower in September at 75 mm (3.0 in), occurring over 14 days, compared to August, which sees 99 mm (3.9 in) over 13 days. Humidity is slightly higher in September at 89%, compared to 84% in August, contributing to a more saturated feel as summer transitions into autumn. For detailed insights, you can check Viljandi weather in August.
September and October display notable differences in weather patterns as the transition from summer to autumn unfolds. In September, temperatures range from a chilly minimum of -2°C (28°F) to a warm maximum of 26°C (79°F), with an average temperature of 12°C (55°F). The month experiences 75 mm (3.0 in) of precipitation over 14 days, accompanied by relatively high humidity at 89%. In contrast, October brings cooler conditions with temperatures dropping to a minimum of -5°C (23°F) and a maximum of 19°C (67°F), resulting in an average of just 7°C (46°F). Precipitation slightly increases to 82 mm (3.2 in) over the same number of rainy days, while humidity rises to 92%. For more detailed information, check out Viljandi weather in October.
September and November present notable differences in weather patterns. In September, temperatures range from a minimum of -2°C (28°F) to a maximum of 26°C (79°F), with an average of 12°C (55°F). This month also sees more warmth and a relatively mild humidity level of 89%, with rainfall totaling 75 mm (3.0 in) over about 14 days.
In contrast, November experiences a significant drop in temperature, with a minimum of -10°C (14°F) and a maximum of 12°C (54°F), averaging just 3°C (38°F). Despite slightly less precipitation at 57 mm (2.2 in) over 11 days, the humidity rises to 93%. This makes November feel much colder and wetter compared to the mild, late summer days of September. For a detailed overview of weather conditions in November, check out Viljandi weather in November.
September and December offer a stark contrast in weather, showcasing the transition from late summer to winter in Viljandi. In September, temperatures range from a mild -2°C (28°F) at night to a comfortable average of 12°C (55°F) during the day, peaking at 26°C (79°F). The month experiences considerable precipitation, with 75 mm (3.0 in) falling over 14 days and a humidity level of 89%. Conversely, December plunges into the depths of winter, with temperatures dropping to a chilling -24°C (-11°F) at night, an average of -1°C (30°F), and a maximum of just 9°C (48°F). This month receives less precipitation, totaling 52 mm (2.1 in) across 13 days, but the humidity slightly increases to 93%. For more detailed information on the winter climate, check Viljandi weather in December.
As September arrives in Viljandi, the weather presents a noticeable transition from the warmth of summer to the crispness of autumn. While temperatures can still reach a pleasant 26°C, the average cools significantly to around 12°C, making it a month of contrasts. Precipitation becomes more frequent, with rainfall occurring on nearly half the days, contributing to an elevated humidity level of 89%. This shift in weather not only enhances the vibrant colors of the changing leaves but also invites a sense of cozy anticipation for the upcoming season. To explore more about the Viljandi climate throughout the year, visit Viljandi Climate.