Last updated: August 27, 2025
December in Postojna, Slovenia showcases a striking winter landscape, with temperatures averaging around 2°C (36°F). The month sees a maximum temperature reaching 13°C (56°F), while the chill can plunge to a brisk -13°C (9°F) on colder nights. Precipitation is notable, with about 161 mm (6.3 in) spread over 11 days, contributing to a humid atmosphere with an impressive 88% humidity level. This blend of cool temperatures and frequent moisture creates a unique and captivating winter experience in Postojna, perfect for exploring the stunning natural scenery.
In December, Postojna, Slovenia experiences a notable drop in temperatures as winter settles in. With minimums plunging to -13°C (9°F), the month showcases the chill of the season, while the average temperature hovers around 2°C (36°F), offering a crisp but bearable cold. Daytime highs reach a modest 13°C (56°F), making it one of the last months before the deep winter freeze fully takes hold. This transitional period is marked by a blend of frosty nights and cool days, inviting visitors to enjoy the enchanting winter landscapes while embracing the holiday spirit in this picturesque locale.
December in Postojna, Slovenia, typically ushers in a substantial amount of precipitation, totaling 161 mm (6.3 in) over the course of 11 days. This month's rainfall stands as a significant contributor to the year's wetter months, following a pattern where precipitation tends to peak during late autumn and early winter. Notably, December's rainfall is indeed lower than the preceding month of November, which recorded 176 mm (6.9 in), yet it remains higher than the earlier months of the season. The gradual increase in rainfall from the drier months of summer reflects a clear seasonal trend, as the region transitions into its wetter winter period, culminating in ample moisture that supports the lush landscape characteristic of Slovenia’s winter scenery.
December in Postojna, Slovenia, presents a return to elevated humidity levels, measuring 88%, closely mirroring the high figures of January and November. This winter month comes on the heels of a gradual decrease in humidity from the summer peak, where humidity dipped to a refreshing 51% in August. As the year progresses, the trend showcases a steady rise in moisture from the late summer months, with particularly notable spikes in October and November as the cold sets in. By December, residents and visitors alike can expect a more humid atmosphere reminiscent of the earlier winter, creating a crisp yet damp backdrop to the enchanting winter landscapes of this captivating region.
In December, Postojna, Slovenia, experiences a UVA Index of 2, indicating a low exposure category that allows for a burn time of approximately 45 minutes. This gradual decline in UV levels from the peak of summer—where values soared to a very high 9—marks a significant shift towards milder sun exposure. As the months transition from November's moderate index of 3 back to low, it's a reminder for residents and visitors alike that winter months provide a safer environment for outdoor activities without the high risks associated with UV radiation seen earlier in the year. For more insights on UV trends throughout the year, check out the detailed report on Postojna UV Index.
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As December blankets Postojna, Slovenia, with its crisp winter air, the sunshine still graces the region with 211 hours of daylight, providing a gentle transition into the colder months. This marks a slight decline from the vibrant November of 222 hours but is part of a broader trend observed throughout the year. From the 179 hours in January to a peak of 429 hours in July, each month showcases the region's dynamic seasonal sunshine, culminating in an average of more than 300 hours during the burgeoning spring and summer months. While December may dim compared to the summer's brilliance, it reflects the perfect balance of light that beautifully defines Postojna's unique charm during the winter season.
In Postojna, Slovenia, the probability of sunny weather in December stands at 33%, a figure that mirrors the trends seen in earlier winter months like November, which has a lower 26% chance. As the year progresses towards spring, sunlight becomes more frequent, with March showcasing a notable 58% likelihood. This indicates that while December days can be overcast and chilly, there is still a reasonable chance of enjoying some sunny moments amidst the winter gloom. Visitors can anticipate a mix of crisp air and potential sunshine, making it a unique time to experience the enchanting beauty of Postojna.
In Postojna, Slovenia, the daylight duration experiences a noticeable ebb and flow throughout the year, reaching its lowest point in December, when the sun graces the sky for only 8 hours. This declining trend begins in November and continues into the winter months, contrasting sharply with the vibrant summer months of June and July, where daylight peaks at an impressive 15 hours. As the year progresses from the longer days of spring and summer, culminating in April with 13 hours, the gradual reduction in daylight becomes evident, aligning with the onset of winter. Despite the limited daylight in December, it's a time that embraces the coziness of winter warmth, inviting residents to relish in the magic of the season while awaiting the gradual return of longer days ahead.
As December settles over Postojna, Slovenia, the average wind speed drops to 2.0 m/s (4 mph), reflecting a trend of gentler breezes that characterize the winter months. Following a slightly brisker October, which boasted an average of 3.0 m/s (7 mph), the winds soften, mirroring the tranquil atmosphere of the holiday season. Interestingly, this decrease continues a pattern seen from June onward, where the wind speeds tend to hover around 2.1 m/s (5 mph) or lower, suggesting a cooler, calmer climate as the year winds down. The overall subtlety in December's winds contrasts sharply with the spring months, which feature higher averages, reminding us of the seasonal shifts that define Postojna's enchanting landscape.
Weather in Postojna varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Postojna, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January weather exhibit some notable differences. In December, temperatures range from a chilly minimum of -13°C (9°F) to a maximum of 13°C (56°F), with an average temperature of 2°C (36°F). This month also sees a substantial amount of precipitation, totaling 161 mm (6.3 in) over 11 days, while maintaining a high humidity level of 88%.
In contrast, January experiences slightly colder temperatures, with a minimum of -14°C (7°F) and a maximum of 11°C (52°F), resulting in an average temperature of 0°C (33°F). Precipitation is significantly lower at 72 mm (2.8 in) over just 8 days, but humidity remains consistent at 88%. For more detailed weather insights, you can refer to Postojna weather in January.
December and February present distinct weather patterns, despite being just a couple of months apart. In December, temperatures range from a chilly -13°C (9°F) at night to a milder 13°C (56°F) during the day, with an average temperature of 2°C (36°F). This month also sees higher precipitation at 161 mm (6.3 in) over 11 days and a humidity level of 88%. In contrast, February experiences slightly warmer temperatures, with a minimum of -12°C (10°F) and a maximum reaching up to 19°C (67°F), averaging 3°C (38°F). Precipitation decreases to 128 mm (5.0 in) spread over 10 days, accompanied by a lower humidity of 82%. For a more detailed look at the weather during this month, you can visit Postojna weather in February.
December and March present contrasting weather patterns. In December, temperatures range from a chilling -13°C (9°F) at night to a mild 13°C (56°F) during the day, with an average temperature of 2°C (36°F). This month is also characterized by higher precipitation, totaling 161 mm (6.3 in) over 11 rainy days, coupled with a high humidity level of 88%. In contrast, March sees a slightly broader temperature range, with nighttime lows plunging to -17°C (2°F) and daytime highs reaching a pleasant 21°C (70°F), resulting in an average of 5°C (42°F). Precipitation is less abundant in March, measuring 97 mm (3.8 in) over the same number of rainy days, and the humidity drops to a more comfortable 73%. For a more detailed look at March weather, visit Postojna weather in March.
December and April present quite contrasting weather patterns. In December, temperatures range from a chilly -13°C (9°F) at their lowest to a milder 13°C (56°F) at their highest, with an average temperature of around 2°C (36°F). The month is marked by significant precipitation of 161 mm (6.3 in) spread across 11 days, coupled with high humidity at 88%. In stark contrast, April offers a more temperate experience, with minimum temperatures dropping to -10°C (14°F) but can rise significantly to a maximum of 25°C (78°F), averaging around 10°C (50°F). Precipitation in April is lower, at 115 mm (4.5 in) over 12 days, and humidity is also reduced to a more comfortable 73%. For a closer look at what to expect in April, you can check Postojna weather in April.
In December, the weather is chilly, with temperatures ranging from a minimum of -13°C (9°F) to a maximum of 13°C (56°F), and an average of only 2°C (36°F). The month sees significant precipitation, totaling 161 mm (6.3 in) over about 11 days, accompanied by a high humidity level of 88%. In contrast, May offers a much warmer climate, with temperatures that vary from a minimum of 1°C (34°F) to a pleasant maximum of 26°C (79°F), yielding an average of 14°C (57°F). The month is also wetter, with 206 mm (8.1 in) of precipitation spread over 20 days, but humidity is notably lower at 70%. For more details on weather conditions in May, check out Postojna weather in May.
December and June present stark contrasts in weather conditions. In December, temperatures can plunge to a minimum of -13°C (9°F) with an average of 2°C (36°F), reaching a maximum of 13°C (56°F). The month is characterized by high humidity at 88% and significant precipitation averaging 161 mm (6.3 in) over 11 days. In contrast, June welcomes warmth with a minimum temperature of 6°C (44°F) and an average of 19°C (67°F), soaring up to a maximum of 35°C (95°F). While June experiences lower precipitation at 110 mm (4.3 in) spread across 12 days, its humidity is also more comfortable at 69%. For more insights on this month, check out Postojna weather in June.
December and July present stark contrasts in weather conditions. In December, temperatures can drop to a chilling low of -13°C (9°F) and average around 2°C (36°F), Peaking at a mild 13°C (56°F). The month experiences high humidity at 88% and considerable precipitation, with 161 mm (6.3 in) spread over 11 days. In contrast, July brings much warmer temperatures, with lows of 9°C (48°F), averages of 20°C (68°F), and highs reaching 33°C (91°F). Although July encounters slightly less precipitation at 130 mm (5.1 in) across 14 days, the humidity is significantly lower at 63%. For more insights, check out Postojna weather in July.
In December, temperatures in Postojna can drop significantly, with lows reaching as low as -13°C (9°F) and average highs around 2°C (36°F). The month typically experiences high humidity levels at 88% and sees considerable precipitation, averaging 161 mm (6.3 in) over about 11 days. In contrast, August boasts a much warmer climate, with temperatures ranging from a minimum of 9°C (48°F) to a maximum of 34°C (93°F) and an average temperature of 20°C (69°F). The humidity in August is notably lower at 51%, and while it still experiences precipitation, it averages 126 mm (5.0 in) spread over 13 days. For a more detailed look at the conditions during this summer month, check out Postojna weather in August.
In December, temperatures drop significantly, with an average of 2°C (36°F) and nighttime lows reaching as low as -13°C (9°F), while September enjoys milder weather with an average of 15°C (60°F) and maximums of 28°C (83°F). Moreover, December is characterized by high humidity at 88%, contributing to a chilly atmosphere, compared to the more comfortable 64% humidity typically found in September. Precipitation levels also vary, with December receiving 161 mm (6.3 in) over 11 days, whereas September sees slightly higher precipitation at 205 mm (8.1 in) across 13 days. For more detailed insights on the weather in September, you can check Postojna weather in September.
In comparing the weather of December and October, it is evident that December is significantly colder, with a minimum temperature dropping to -13°C (9°F) and an average of 2°C (36°F), compared to October's milder minimum of 0°C (32°F) and average of 11°C (52°F). Additionally, December experiences more precipitation, totaling 161 mm (6.3 in) over 11 days, while October sees 127 mm (5.0 in) falling over just 10 days. Humidity levels are also higher in December at 88%, compared to 83% in October. For more specific details on the weather in October, you can refer to Postojna weather in October.
December weather in Postojna is generally colder than November, with minimum temperatures dropping to -13°C (9°F) compared to November's -9°C (16°F). The average temperature also sees a decline from 6°C (43°F) in November to 2°C (36°F) in December, while maximum temperatures remain lower at 13°C (56°F) in December versus 18°C (65°F) in November. Precipitation levels are slightly reduced in December at 161 mm (6.3 in) over 11 days, compared to 176 mm (6.9 in) across 12 days in November. Humidity remains high in both months, with December at 88% and November at 89%. For more detailed information, you can visit Postojna weather in November.
December in Postojna marks a notable shift in weather compared to other months, as the chill of winter firmly sets in. With average temperatures hovering around 2°C (36°F), the brisk air invites a cozy atmosphere, contrasting sharply with the warmer months. Days are often gray and damp, as December tends to experience significant precipitation, resulting in a distinctive 11 days of rainfall throughout the month. The high humidity, reaching 88%, contributes to a pervasive chill, making it the perfect time to explore indoor attractions. As you plan your visit, don’t miss out on the unique December charm of Postojna, and for a comprehensive overview of its climate throughout the year, check out Postojna Climate.