Last updated: August 27, 2025
In Koper, Slovenia, December presents a chilly atmosphere characterized by a maximum temperature of 15°C (60°F) and an average of 7°C (44°F), with nighttime lows dipping to -1°C (30°F). This month typically sees 12 days of precipitation, accumulating to about 150 mm (5.9 in), making it one of the wetter months in the region. High humidity levels around 88% contribute to the crisp, cool feel of the air, setting a quintessential winter scene perfect for cozy indoor activities and festive gatherings.
As December settles in Koper, Slovenia, temperatures begin to reflect the chill of winter, with minimums hovering around -1°C (30°F). The average temperature drops to a cool 7°C (44°F), creating a brisk atmosphere ideal for cozy gatherings or exploring the town’s festive charm. With max temperatures reaching up to 15°C (60°F), the month showcases a notable decline from the milder conditions of November, which had averaged 11°C (52°F). This shift marks a transition into the colder months, inviting winter enthusiasts to enjoy the serene beauty and seasonal celebrations that Koper has to offer.
December in Koper, Slovenia, marks a significant transition in the year’s precipitation patterns, with an impressive 150 mm (5.9 in) of rainfall accumulated over 12 rainy days. This is a slight decrease from the remarkably wet November, which recorded 176 mm (6.9 in), yet it illustrates the consistent dampness that characterizes the region as winter sets in. As the year closes, the cumulative rainfall reflects a pattern of increasing precipitation throughout the autumn months, indicating a trend toward wetter conditions. With December’s rainfall contributing to an overall upward trend since the drier summer months, it’s clear that Koper's climate embodies a rich seasonal cycle, blending the chill of winter with the lingering warmth of autumn.
In Koper, Slovenia, December sees a return to higher humidity levels, measuring at 88%. This marks a noticeable increase from the preceding month of November, which recorded 89%. As the year wraps up, humidity levels tend to rise again, contrasting sharply with the drier summer months, where July and August exhibited much lower averages of 63% and 51%, respectively. Following this summer dip, the trend indicates a gradual uptick from October’s 83%, hinting that Koper experiences a shift towards a wetter and cooler climate as winter approaches. Overall, the humidity levels exhibit a distinct seasonal pattern, showcasing both summer's dry air and winter's damp embrace.
In December, Koper, Slovenia experiences a low UV Index of 2, making it a relatively safe time for outdoor activities. With a burn time of 45 minutes, residents and visitors can enjoy the cool winter days without heavy concern for sun exposure. This month follows a notable upward trend from the sunnier months of summer, where UV levels peaked at 9, indicating very high exposure risk in June and July. As we transition from the vibrant summer months to the quieter winter period, the UV Index gradually decreases, reflecting a pattern that emphasizes caution during the sunnier spring and summer but allows for more relaxed exposure as the year closes. For more detailed data and insights, visit Koper UV Index.
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In Koper, Slovenia, the end of the year welcomes a gentle decline in sunshine hours, with December basking in 207 hours of bright light. This reduction follows a spectacular summer, where July shines the brightest with an impressive 430 hours, before slowly tapering off into the cozy ambiance of winter. As the year progresses, we observe a transition from the long, sunlit days of June and July to the milder, yet still vibrant, December. While the eventual loss of sunlight might signal the approach of winter, it also brings the charm of Koper’s festive spirit, making every sun-drenched hour in December a cherished moment.
In Koper, Slovenia, the likelihood of sunny weather in December hovers around 38%, signaling a shift from the more favorable conditions found in the previous months. While January starts relatively low at 32%, February sees a notable increase to 41%, leading into the spring months when sunshine becomes more prevalent, peaking at 63% in March. As the year winds down, there's a downward trend in sunshine probabilities, with December slightly more favorable than November's 37%. This pattern highlights December as a transitional month, where the promise of clearer skies is present but not guaranteed, inviting visitors to embrace the region's serene winter charm, even amidst the clouds.
In Koper, Slovenia, the December daylight duration marks the culmination of a gradual decline in sunlight as the year progresses. With only 8 hours of daylight, December sits at the lower end of the spectrum, in stark contrast to the 15 hours enjoyed during the peak months of June and July. This trend underscores the shift from the vibrant, sunlit days of summer to the shorter, cozier winter afternoons. As the year transitions from November's 9 hours to December's 8, it signals a time for reflection and warmth, inviting residents to embrace the beauty of the season while the sun takes its shorter bows across the horizon.
As December settles in Koper, Slovenia, the average wind speed drops to 2.3 m/s (5 mph), marking it among the calmest months of the year. This gentle breeze comes on the heels of a notable increase in wind activity during the autumn months, peaking at 3.7 m/s (8 mph) in November. The trend throughout the year shows a peak in wind intensity during the transition from fall to winter, with winds generally stronger in the late autumn as they prepare for the more tranquil December. With such subdued winds, Koper's coastal charm is highlighted, making it a serene destination for those looking to enjoy the peaceful winter ambiance along the Adriatic coast.
Weather in Koper varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Koper, focusing on differences in temperature, rainfall, humidity, and UV levels.
In December, the weather tends to be milder, with temperatures ranging from a minimum of -1°C (30°F) to a maximum of 15°C (60°F) and an average of around 7°C (44°F). This month experiences significant precipitation, totaling 150 mm (5.9 in) over approximately 12 days, contributing to a high humidity level of 88%.
In contrast, January presents colder conditions, characterized by lower temperatures that drop to a minimum of -7°C (20°F) and an average of 5°C (41°F), peaking at 13°C (56°F). Precipitation is also reduced to 56 mm (2.2 in) across just 7 days while maintaining the same humidity level of 88%. This shift highlights a transition into a colder and drier winter month. For more information on January weather specifics, you can view Koper weather in January.
In December, the weather tends to be slightly milder with average temperatures around 7°C (44°F), peaking at a maximum of 15°C (60°F), while dipping to a minimum of -1°C (30°F). This month also sees considerable precipitation, totaling 150 mm (5.9 in) over approximately 12 days, and experiences a high humidity level of 88%.
Conversely, February brings colder conditions with a lower minimum temperature of -6°C (22°F), though the average remains the same at 7°C (44°F). The maximum temperature can reach 19°C (67°F). Precipitation decreases to 118 mm (4.6 in) across about 10 days, and humidity also drops to 82%. For more details about the weather patterns in February, visit Koper weather in February.
December and March exhibit distinctly different weather patterns. In December, temperatures range from a chilly minimum of -1°C (30°F) to a comfortable maximum of 15°C (60°F), with an average of 7°C (44°F). This month also sees considerable precipitation, averaging 150 mm (5.9 in) over 12 days, contributing to a high humidity level of 88%. In contrast, March experiences slightly milder temperatures, with lows of -7°C (20°F) and highs reaching up to 21°C (70°F), averaging 9°C (48°F). Precipitation decreases significantly to 71 mm (2.8 in) across just 8 days, and humidity drops to a more comfortable 73%. For more insights on March weather, you can visit Koper weather in March.
December and April present contrasting weather patterns. In December, temperatures hover between -1°C (30°F) at their lowest and reach a maximum of 15°C (60°F), with an average of 7°C (44°F). The month is characterized by high humidity levels at 88% and considerable precipitation of 150 mm (5.9 in) over 12 days. In contrast, April enjoys a milder climate, with minimum temperatures of 1°C (34°F) and highs soaring up to 25°C (77°F), averaging 13°C (55°F). The month sees less precipitation at 103 mm (4.0 in) over just 10 days and lower humidity at 73%. For more detailed insights, explore Koper weather in April.
December and May present contrasting weather experiences, highlighting the shift from winter to spring. In December, temperatures range from a chilly -1°C (30°F) at the minimum to a mild 15°C (60°F) at the maximum, accompanied by high humidity at 88%. The month sees considerable precipitation, totaling 150 mm (5.9 in) over 12 days, creating a damp and chilly atmosphere. In contrast, May offers much warmer conditions, with temperatures starting at a comfortable 7°C (46°F) and peaking at 27°C (81°F). Although it experiences slightly less precipitation at 142 mm (5.6 in) spread over 17 days, the humidity drops to a more pleasant 70%. For a detailed look at specific weather conditions in May, you can visit Koper weather in May.
December weather is characterized by chilly temperatures, with lows dipping to -1°C (30°F) and an average of 7°C (44°F). The month sees considerable precipitation, averaging 150 mm (5.9 in) over 12 days, resulting in high humidity levels around 88%. In stark contrast, June brings a much more temperate climate, with a minimum temperature of 11°C (53°F) and an average high of 22°C (72°F), peaking at 33°C (92°F). Rainfall decreases significantly to 87 mm (3.4 in) over just 8 days, and humidity drops to a comfortable 69%. For more detailed insights on June weather, you can check out Koper weather in June.
December and July present stark contrasts in weather. December experiences cooler temperatures, with a minimum of -1°C (30°F) and an average of 7°C (44°F), making it a much chillier month overall. In contrast, July boasts a milder climate, with temperatures ranging from a minimum of 16°C (61°F) to an average of 24°C (75°F) and reaching highs of 33°C (91°F). Precipitation is notably higher in December, with 150 mm (5.9 in) over 12 days compared to July's 65 mm (2.6 in) over just 8 days. Additionally, December’s humidity levels are significantly elevated at 88%, while July enjoys a more comfortable 63%. This seasonal variation makes each month distinctly unique in Koper. For a deeper look at July's weather specifics, you can check out Koper weather in July.
December and August present stark contrasts in weather. In December, temperatures range from a chilly -1°C (30°F) to a mild 15°C (60°F), with an average of 7°C (44°F). This month experiences significant precipitation, totaling 150 mm (5.9 in) over about 12 days, and the humidity remains quite high at 88%. In contrast, August offers a warm respite with temperatures ranging from a pleasant 15°C (59°F) to a hot 34°C (94°F), averaging around 25°C (77°F). Precipitation is much lower in August, at 70 mm (2.7 in) over roughly 7 days, and humidity is significantly reduced to 51%. For more details on the weather during this lively summer month, visit Koper weather in August.
In comparing the weather between December and September, notable differences emerge in both temperature and humidity. December tends to be much cooler, with average temperatures ranging from a chilly minimum of -1°C (30°F) to a maximum of 15°C (60°F), while September enjoys milder conditions, with temperatures fluctuating between a minimum of 9°C (49°F) and a maximum of 32°C (90°F). Precipitation levels are relatively high in both months, with December experiencing about 150 mm (5.9 in) over 12 days, compared to September's 164 mm (6.4 in) across 10 days. Additionally, December has a higher humidity level at 88%, while September is noticeably drier, with humidity sitting at 64%. For more detailed information on September conditions, you can check Koper weather in September.
December weather presents a noticeable shift compared to October, with lower temperatures and higher humidity levels. While October enjoys milder conditions with an average temperature of 15°C (59°F), December's average drops to 7°C (44°F), frequently reaching minimums around -1°C (30°F). Additionally, December experiences increased precipitation of 150 mm (5.9 in) over 12 days, compared to October's 107 mm (4.2 in) across just 10 days. For more detailed information on October weather, you can refer to Koper weather in October.
In comparing the weather of December and November, December tends to be slightly colder, with average temperatures ranging from a minimum of -1°C (30°F) to a maximum of 15°C (60°F), while November enjoys milder temperatures, averaging between 1°C (34°F) and 20°C (68°F). Precipitation levels are also noteworthy; December receives approximately 150 mm (5.9 in) of rain over 12 days, whereas November sees a bit more, with 176 mm (6.9 in) over the same number of days. Humidity levels remain quite similar in both months, with December at 88% and November at 89%. For more details on November weather, visit Koper weather in November.
As winter settles in, Koper experiences a distinct change in weather during December compared to other months. With a chill in the air, temperatures dip to an average of 7°C (44°F), marked by occasional frosty nights, while humidity levels soar to 88%, creating a crisp atmosphere. The city sees about 12 days of rain, contributing to a total precipitation of 150 mm (5.9 in), making this month one of the wetter periods of the year. This shift not only highlights the seasonal transition but also sets the stage for the enchanting winter ambiance that envelops Koper. For a more in-depth look at what to expect throughout the year, check out Koper Climate.