September Weather in Kaunas, Lithuania

Last updated: August 21, 2025

September in Kaunas, Lithuania presents a transitional climate, with temperatures soaring to a maximum of 28°C (82°F) during the warmer days while averaging around 14°C (57°F). As autumn approaches, brisk nights can dip to a minimum of -2°C (29°F). Rainfall is quite common, with an average precipitation of 65 mm (2.6 in) spread across 11 days, contributing to the 83% humidity that characterizes this time. Visitors can experience a dynamic mix of mild warmth and crisp coolness, making it a month of delightful contrasts.

September Temperature in Kaunas

As September unfolds in Kaunas, Lithuania, the transition from the warmth of summer to the crispness of autumn is palpable. With temperature lows dipping to around -2°C (29°F) and averages settling around a mild 14°C (57°F), this month offers a refreshing change after the heat of July and August. The maximum temperature can reach a comfortable 28°C (82°F), making early September particularly pleasant for outdoor activities. However, as the month progresses, expect a gradual cooling that heralds the approaching fall, hinting at the chilly months ahead. This bittersweet shift not only invites locals to enjoy the last vestiges of warm days but also sets the stage for the colorful transformation of the landscape that autumn brings.

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

The chart illustrates September temperature patterns in Kaunas, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Kaunas, 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).
JanFebMarAprMayJunJulAugSepOctNovDec293036455565666557484032
Data source: Temperature data for Kaunas 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 Kaunas

In September, Kaunas experiences a notable transition as it averages 65 mm (2.6 in) of precipitation over 11 days, marking a shift towards the wetter months of autumn. This month's rainfall is higher than in the earlier summer months, reflecting a gradual increase in precipitation that peaks in July, followed by August's 84 mm (3.3 in). As the year progresses, September serves as a reminder of the changing seasons, with precipitation levels maintaining consistency with those in October, which also averages 66 mm (2.6 in). The trend indicates a pattern of increased rainfall as summer wanes, paving the way for the cooler and wetter months ahead.

September Precipitation Trends in Kaunas

The chart displays monthly precipitation patterns in Kaunas, 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 Kaunas, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec503843456355958465664955
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Kaunas

In September, Kaunas experiences a noticeable drop in humidity compared to the sweltering summer months, settling at a comfortable 83%. This moderate level is a part of a gradual decline from the high summer humidity of 74% in August, creating a refreshing transition into autumn. As the year progresses, humidity levels begin to rise again, peaking in the winter months, with January and February reaching a substantial 94% and 92%, respectively. Overall, September serves as a perfect bridge, offering a pleasant balance before the onset of the more humid fall and winter seasons.

September Average Humidity in Kaunas

This chart illustrates the average monthly humidity levels in Kaunas, 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 Kaunas is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec94%92%90%86%72%74%76%74%83%91%93%95%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Kaunas

In September, Kaunas, Lithuania, experiences a moderate UV Index of 5, signaling a blend of summer warmth and the approaching autumn chill. With a burn time of just 30 minutes, it’s a reminder that, despite lower UV readings compared to the peak summer months, sun safety remains important. As the season transitions, September follows a pattern seen throughout the year, with the UV intensity gradually declining from the high summer values of 6 and 7 back to more manageable levels. This month serves as a gentle nudge towards outdoor enjoyment with due diligence, making it a great time to relish the crisp air while still being mindful of sun exposure. For more information on UV levels throughout the year, visit Kaunas UV Index.

Maximum UV Index Levels in Kaunas for September

The chart shows the monthly maximum UV Index (UVI) for Kaunas 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 Kaunas typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec124567765321
Data source: Kaunas 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 Kaunas

As September graces Kaunas, Lithuania, it offers a delightful 301 hours of sunshine, marking a gentle decline from the sun-drenched summer months. Following the peak of 444 hours in June, the sunshine begins to soften, yet September still radiates warmth, providing a perfect backdrop for outdoor activities and scenic strolls through the city’s vibrant streets. This month acts as a bridge between the lush brightness of summer and the cooler embrace of autumn, as the daylight hours decline steadily—dropping sharply to only 225 hours in October. With its golden hues and a touch of crispness in the air, September remains a cherished time for locals and visitors alike, celebrating the last glimpses of summer's glow before the winter takes hold.

Monthly Sunshine Duration in Kaunas: September Highlighted

The September sunshine duration represents the total number of hours Kaunas 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.
JanFebMarAprMayJunJulAugSepOctNovDec77h169h260h339h419h444h435h388h301h225h117h94h
Data source: Kaunas September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Kaunas During September

In September, the chance of sunny weather in Kaunas, Lithuania, stands at 32%, reflecting a transitional period as summer gives way to autumn. This percentage is notably higher than the earlier months of the year, particularly January and February, which struggle with low sun exposure, at just 8% and 26% respectively. Interestingly, September sees a return to similar probabilities found in the late spring and early summer months, such as May and June, which hover around the same range. Although it’s a modest opportunity for sunshine, this time of year allows for pleasant weather—the perfect backdrop for enjoying the city's cultural offerings before the chill of autumn sets in.

Percentage of Sunny Days in September in Kaunas

The chart illustrates the percentage of sunny days in Kaunas 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 Kaunas experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec8%26%36%33%32%58%53%27%32%41%17%18%
Data source: Kaunas September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Kaunas in September

As September arrives in Kaunas, Lithuania, the daylight begins to wane, transitioning from the vibrant summer months. With 12 hours of daylight, this time of year marks a gentle decrease from the 16 hours enjoyed in May and June, settling into a more moderate light that remains favorable for outdoor activities. The trend of gradually shortening days continues into October, hinting at the impending embrace of autumn. This shift not only alters the landscape but also invites a cozy atmosphere, perfect for enjoying the rich hues of fall. September’s twilight serves as a reminder of nature's rhythms, blending the lingering warmth of summer with the crispness of the seasons ahead.

Average Daylight Hours in Kaunas for September

The chart illustrates the variation in daylight duration in Kaunas throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec7h 51m9h 41m11h 53m14h 9m16h 9m17h 14m16h 39m14h 50m12h 39m10h 25m8h 23m7h 16m
Data source: Kaunas daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Kaunas

As September unfolds in Kaunas, Lithuania, the wind begins to pick up, averaging 3.7 m/s (8 mph)—a slight increase compared to the stillness of summer months like June and July, which saw only 2.6 m/s (6 mph) and 2.7 m/s (6 mph), respectively. This gentle yet noticeable rise in average wind speed signals the transition into autumn, reminiscent of the brisk days ahead. While September's winds remain milder than those of the upcoming months—October and November both averaging 4.2 m/s (10 mph)—they provide a refreshing contrast to the warmth of summer, encouraging residents and visitors alike to embrace the changing season with open arms.

Average September Wind Speed in Kaunas

The chart displays monthly wind speed patterns in Kaunas, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.53.53.73.93.72.62.73.23.7 m/s4.24.23.9
Data source: Kaunas September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Kaunas Compares to Other Months

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

September and January present a stark contrast in weather patterns. In September, temperatures range from a chilly -2°C (29°F) at night to a pleasant 28°C (82°F) during the day, averaging around 14°C (57°F). The month experiences about 65 mm (2.6 in) of precipitation over 11 days, with humidity at a relatively comfortable 83%. In contrast, January sees much colder conditions, with temperatures plummeting to a minimum of -25°C (-13°F) and a maximum of only 7°C (46°F), averaging -1°C (30°F). While January receives slightly less precipitation at 50 mm (2.0 in) over the same number of days, it has a higher humidity level of 94%. For more detailed information, you can refer to Kaunas weather in January.

September and February present stark contrasts in weather. In September, temperatures range from a mild -2°C (29°F) to a warm 28°C (82°F), with an average of 14°C (57°F). The month experiences 65 mm (2.6 in) of precipitation over 11 days, contributing to a relative humidity of 83%. In comparison, February is considerably colder, with temperatures dipping as low as -22°C (-7°F) and only reaching a maximum of 11°C (52°F). The average temperature sits at -1°C (30°F), and it sees less precipitation at 37 mm (1.5 in) across 9 days, yet the humidity is higher at 92%. For more detailed insights, check out Kaunas weather in February.

In comparing the weather between September and March, a notable contrast emerges. September enjoys a milder climate with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 28°C (82°F), and an average temperature of 14°C (57°F). The month sees about 65 mm (2.6 in) of precipitation over 11 days, with humidity levels at 83%. In stark contrast, March experiences colder conditions, with temperatures dipping as low as -19°C (-2°F) and peaking at 16°C (62°F), averaging only 2°C (36°F). While March has slightly less precipitation at 42 mm (1.7 in) over 12 days, the humidity is higher at 90%. For those interested in more detailed information, check out Kaunas weather in March.

When comparing the weather in September and April, we notice significant differences in temperature and precipitation. September boasts a more moderate temperature range, with a minimum of -2°C and a maximum of 28°C, leading to an average temperature of 14°C. This month experiences 65 mm of precipitation over 11 days, coupled with humidity levels around 83%. In contrast, April typically has lower average temperatures, with a minimum of -7°C and a maximum of 26°C, resulting in an overall average of 7°C. It also sees less precipitation at 45 mm over 10 days, but slightly higher humidity at 86%. For more detailed insights on April weather, you can visit Kaunas weather in April.

September and May showcase similar temperature ranges, with both months experiencing minimum temperatures of -2°C (29°F). However, September tends to be slightly warmer overall, averaging 14°C (57°F) compared to May's average of 13°C (55°F). The maximum temperatures are comparable, with September reaching up to 28°C (82°F) and May peaking at 29°C (84°F). Precipitation levels are fairly consistent, with September receiving 65 mm (2.6 in) and May a touch less at 63 mm (2.5 in), both over 11 days. One notable difference is the humidity, where September’s humidity is higher at 83%, while May enjoys a more moderate 72%. For more detailed information about May weather, check out Kaunas weather in May.

In comparing the weather between September and June, we can observe some notable differences. September experiences a wider temperature range with minimums dropping to -2°C (29°F) and maximums reaching up to 28°C (82°F), while June has milder temperatures, starting at 3°C (37°F) and peaking at 34°C (93°F). Precipitation is slightly higher in September at 65 mm (2.6 in) across 11 days compared to June's 55 mm (2.1 in) over 10 days. Additionally, September tends to be more humid, with an average humidity of 83%, compared to June's 74%. For more details about June's weather, visit Kaunas weather in June.

When comparing the weather in September and July, a noticeable shift in temperature and humidity is evident. September experiences cooler temperatures, with a minimum of -2°C (29°F) and an average of 14°C (57°F), while July boasts milder conditions, with a minimum of 7°C (45°F) and an average of 19°C (66°F). The maximum temperatures in July reach up to 34°C (93°F), significantly higher than September's maximum of 28°C (82°F). Additionally, September sees a higher humidity level at 83% compared to July's 76%, along with increased precipitation in September, totaling 65 mm (2.6 in) over 11 days versus 95 mm (3.7 in) over 12 days in July. For further details, you can check Kaunas weather in July.

In comparing the weather patterns of August and September, we see notable differences in temperature, precipitation, and humidity. August generally experiences warmer conditions, with average temperatures reaching 18°C (65°F) and maximums soaring to 32°C (91°F). In contrast, September has a more varied temperature range, with a minimum of -2°C (29°F) and an average of 14°C (57°F), indicating a significant cooling trend as summer transitions to autumn. Additionally, August receives slightly more precipitation, totaling 84 mm (3.3 in) over 14 days, while September sees a reduction to 65 mm (2.6 in) across 11 days. Humidity levels also differ, as September exhibits a higher average humidity at 83% compared to 74% in August. For more detailed information on August weather, you can visit Kaunas weather in August.

September and October display notable differences in weather patterns. In September, temperatures range from a minimum of -2°C (29°F) to a maximum of 28°C (82°F), with an average of 14°C (57°F). The month sees about 65 mm (2.6 in) of precipitation over 11 days, while the humidity levels are around 83%. In contrast, October tends to be cooler, with temperatures dropping to a minimum of -3°C (28°F) and a maximum of 22°C (72°F), averaging 9°C (49°F). Precipitation slightly increases to 66 mm (2.6 in) spread over 14 days, and humidity rises to 91%. For a detailed look, you can check out Kaunas weather in October.

In September, the weather is relatively warm with temperatures ranging from a minimum of -2°C (29°F) to a maximum of 28°C (82°F), resulting in an average temperature of 14°C (57°F). Rainfall is moderate at 65 mm (2.6 in) over 11 days, and humidity sits at a comfortable 83%. In contrast, November brings much colder temperatures, with a minimum of -7°C (20°F) and a maximum of 16°C (61°F), averaging just 5°C (41°F). Precipitation decreases slightly to 49 mm (1.9 in) over 12 days, but humidity rises to 93%, making the air feel quite damp. For more details on November weather, visit Kaunas weather in November.

September and December exhibit stark contrasts in weather conditions. In September, temperatures range from a refreshing low of -2°C (29°F) to a warm high of 28°C (82°F), with an average of 14°C (57°F). The month experiences approximately 65 mm (2.6 in) of precipitation over 11 days and has a humidity level of 83%.

In contrast, December sees much colder temperatures, with a minimum of -15°C (6°F), an average of 0°C (33°F), and a maximum of 10°C (50°F). This winter month has slightly less precipitation at 55 mm (2.2 in), but it occurs over 12 days and is accompanied by high humidity at 95%. To learn more about the experiences of December weather, visit Kaunas weather in December.

Compare Kaunas's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Kaunas

As September arrives in Kaunas, the weather begins to transition from the warmth of summer to the cooler embrace of autumn. Temperatures are notably milder, with a blend of warm days and cool evenings, making it a perfect time for outdoor activities. However, September also sees an increase in precipitation, with more rainy days compared to the drier summer months, contributing to a more humid atmosphere that can feel quite refreshing. The vibrant fall foliage complements the climate, creating a picturesque backdrop for exploring the city. For more insights on how the weather evolves throughout the year, check out Kaunas Climate.