Last updated: August 27, 2025
Koper, Slovenia experiences a delightful May with maximum temperatures reaching up to 27°C (81°F) and an average of 17°C (63°F), offering a pleasant climate for both locals and visitors. While the days are generally warm, nighttime temperatures can drop to a refreshing 7°C (46°F). However, be prepared for some rain, as 142 mm (5.6 in) of precipitation is spread over 17 days, resulting in a humid month with an average humidity level of 70%. Whether you're exploring the charming coastal town or enjoying outdoor activities, Koper's May weather presents a dynamic blend of warmth and refreshing showers.
In May, Koper, Slovenia, emerges as a charming destination, showcasing a delightful transition into warmer temperatures. With minimums rising to 7°C (46°F) and averages reaching 17°C (63°F), the days are pleasantly mild, making it an inviting time for outdoor exploration. The maximum temperatures can soar to a comfortable 27°C (81°F), signifying a clear break from the winter chill. This upward trend from the cooler spring months of April creates an ideal setting for enjoying the picturesque coastal scenery and vibrant local culture, as the city blooms into life with the promise of summer just around the corner.
May stands out in Koper, Slovenia, as the month with the highest precipitation, registering 142 mm (5.6 in) of rain over 17 days. This significant rainfall marks a notable increase from the preceding months, highlighting a seasonal shift as spring transitions into summer. The consistent wet days in May, compared to an average of 10 days for both April and June, illustrate a period where nature fully embraces the lush growth of greenery. As the temperatures rise, the abundant rain not only nourishes the vibrant landscapes but also sets the stage for the dry summer months ahead.
In Koper, Slovenia, May marks a transition toward drier conditions, with humidity levels dropping to 70%. This is a notable decrease from the higher humidity of previous months, such as January and February, which see figures of 88% and 82% respectively. As spring progresses, the humidity levels in Koper gradually decline, paving the way for the warmer, sunnier days of summer. By June, humidity further decreases to 69%, suggesting a trend toward a more comfortable atmosphere. As the year continues, the humidity levels in Koper will continue to fluctuate, illustrating the diverse climatic patterns of this charming coastal town.
As May arrives in Koper, Slovenia, the UV Index climbs significantly, reaching a peak of 8—firmly placing it in the very high exposure category. With a burn time of just 15 minutes, it's essential to be vigilant about sun safety during this month. The trend shows a marked increase in UV intensity from the previous months; April's UV Index of 6 illustrates the rapid shift as we move towards the summer. This annual pattern highlights the importance of protective measures as the days grow longer and sunnier. For more details on UV levels throughout the year, visit Koper UV Index.
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As spring unfolds in Koper, Slovenia, May shines brightly with 372 hours of sunshine, making it one of the sunniest months of the year. The gradual increase in sunlight from January's 182 hours to May reflects the region's awakening from winter, with each month bringing more warmth and light. The transition is particularly striking in April, where 344 hours set the stage for May's radiant embrace. This consistent upward trend peaks in July with 430 hours, hinting at the lush summer that follows. Overall, the sunlight in Koper paints a vivid picture of seasonal change, inviting both residents and visitors to bask in the delightful embrace of spring’s abundant sunshine.
In Koper, Slovenia, the chance of sunny weather in May stands at 40%, a slight dip from the previous month, April, which boasts a 43% likelihood of sunshine. This trend reflects a common pattern where spring transitions into early summer, characterized by fluctuating sunlight. As the year progresses, the chance of sunny days increases significantly, peaking in late summer with August showing 61%. While May may not be the sunniest month, it retains a decent probability of bright days, perfectly blending the remnants of spring's coolness with the anticipation of summer's warmth. Overall, Koper's climate presents a delightful mix of sunny spells, making it an appealing destination as the days get longer and brighter.
As spring gives way to summer in Koper, Slovenia, daylight hours steadily increase, peaking in June with a generous 15 hours of sunlight. In May, the city experiences 14 hours of daylight, reflecting a significant jump from the 13 hours in April. This gradual extension of daylight not only brightens the days but also invites residents and visitors alike to embrace outdoor activities and enjoy the natural beauty of the region. Following this luminous peak, the days begin to shorten as summer wanes, with August still offering 14 hours before the daylight gently dips to 12 hours in September. This cycle of increasing and decreasing daylight beautifully illustrates the rhythmic and dynamic nature of Koper's seasonal changes.
In Koper, Slovenia, May ushers in a slight increase in average wind speed, reaching 3.2 m/s (7 mph), a refreshing transition as spring settles in. Following the gentle breezes of April, which also clocked in at 3.0 m/s, May brings a hint of vitality, creating an inviting atmosphere for outdoor activities. As summer approaches, the wind tends to soften slightly, with June experiencing a dip to 2.2 m/s (5 mph). Interestingly, the wind patterns show a dynamic ebb and flow throughout the year, with the highest speeds recorded in October and November, suggesting that autumn boasts its own fierce charm. Overall, May's breezy weather serves as a delightful prelude to the summer season, making this coastal town a perfect spot for enjoying both the sun and the wind.
Weather in Koper varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Koper, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of May and January, it’s evident that the two months offer contrasting climates. May enjoys milder temperatures, with lows of 7°C (46°F) and highs reaching up to 27°C (81°F), while January experiences much colder conditions, with temperatures plummeting to a minimum of -7°C (20°F) and peaking at just 13°C (56°F).
Precipitation is notably higher in May, totaling 142 mm (5.6 in) over 17 days, which suggests a more frequent occurrence of rain compared to January's 56 mm (2.2 in) spread over only 7 days. Additionally, January has a higher humidity level at 88%, compared to May’s 70%, contributing to a distinctly different feel between the two months. For those interested in the specific climate conditions during the winter season, you can explore Koper weather in January.
May and February present stark contrasts in weather conditions. In May, temperatures range from a minimum of 7°C (46°F) to a maximum of 27°C (81°F), with an average of 17°C (63°F). The month experiences significant precipitation, totaling 142 mm (5.6 in) over about 17 days, coupled with a humidity level of 70%. In contrast, February sees much cooler temperatures, with a low of -6°C (22°F) and a high of 19°C (67°F), averaging at 7°C (44°F). Precipitation is slightly lower at 118 mm (4.6 in) over 10 days, along with higher humidity at 82%. For those interested in the specifics, you can find more information about Koper weather in February.
In comparing the weather of May and March, it's evident that May is generally much warmer and more pleasant. May sees average temperatures ranging from a minimum of 7°C (46°F) to a maximum of 27°C (81°F), while March's temperatures go from as low as -7°C (20°F) to a high of 21°C (70°F). Additionally, May experiences more rainfall, with 142 mm (5.6 in) over 17 days, contrasted with March's 71 mm (2.8 in) across just 8 days. Humidity levels are slightly lower in May at 70% compared to March's 73%, making the warmer temperatures feel more comfortable. For those interested in specific weather details for March, you can check this link: Koper weather in March.
In comparing the weather of April and May, we can see a notable shift in temperatures and precipitation. May experiences higher average temperatures, ranging from a minimum of 7°C (46°F) to a maximum of 27°C (81°F), compared to April's cooler temperatures of 1°C (34°F) to 25°C (77°F). Despite its warmer climate, May also sees increased precipitation, totaling 142 mm (5.6 in) over 17 days, while April records 103 mm (4.0 in) over just 10 days. Interestingly, both months have similar humidity levels, with May at 70% and April slightly higher at 73%. For a closer look at April's weather, you can refer to Koper weather in April.
May and June exhibit a distinct shift in weather patterns, characterized by rising temperatures and reduced precipitation. In May, temperatures range from a brisk minimum of 7°C (46°F) to a pleasant maximum of 27°C (81°F), accompanied by 142 mm (5.6 in) of rainfall spread over 17 days, resulting in a humid environment with 70% humidity. In contrast, June welcomes warmer conditions with temperatures ranging from a minimum of 11°C (53°F) to a maximum of 33°C (92°F). Additionally, the month sees a decrease in precipitation, totaling 87 mm (3.4 in) over just 8 days, and a slight drop in humidity to 69%. For more detailed information, you can check Koper weather in June.
May and July showcase a significant contrast in weather conditions. In May, temperatures range from a cool 7°C (46°F) to a maximum of 27°C (81°F), with an average of 17°C (63°F). The month brings substantial rainfall, with 142 mm (5.6 in) of precipitation spread over 17 days, leading to a higher humidity level of 70%. In contrast, July presents much warmer temperatures, with a minimum of 16°C (61°F), an average of 24°C (75°F), and highs reaching 33°C (91°F). This month experiences considerably less rain, totaling 65 mm (2.6 in) over just 8 days, and a lower humidity at 63%. For more details on July weather, check out Koper weather in July.
In comparing the weather between May and August, we see notable differences in temperature, precipitation, and humidity. May has a cooler climate with an average temperature of 17°C (63°F) and a maximum of 27°C (81°F), while August offers warmer conditions, averaging 25°C (77°F) and peaking at 34°C (94°F). Precipitation in May is significantly higher at 142 mm (5.6 in) over 17 days, compared to just 70 mm (2.7 in) over 7 days in August, indicating drier conditions as summer progresses. Additionally, humidity levels drop from a comfortable 70% in May to a more pleasant 51% in August. For more details, you can check out Koper weather in August.
May and September both offer unique weather experiences, yet they differ significantly in several aspects. In May, temperatures range from a minimum of 7°C (46°F) to a maximum of 27°C (81°F), with an average of 17°C (63°F). The month sees an average precipitation of 142 mm (5.6 in) over 17 days, accompanied by relatively high humidity levels of 70%. Conversely, September typically showcases milder conditions with temperatures ranging from a low of 9°C (49°F) to a high of 32°C (90°F), averaging around 20°C (68°F). Precipitation in September rises slightly to 164 mm (6.4 in) but occurs over fewer days—only 10—resulting in a lower humidity of 64%. These variations create distinct atmospheres for outdoor activities, offering more stable and warmer days in September. For more detailed information, you can check Koper weather in September.
May and October present distinct weather patterns, reflecting the transition from spring to autumn. In May, temperatures range from a minimum of 7°C (46°F) to a maximum of 27°C (81°F), with an average of 17°C (63°F). This month tends to be wetter, with 142 mm (5.6 in) of precipitation spread over 17 days, and a humidity level of 70%. In contrast, October sees milder temperatures, with a minimum of 6°C (44°F), an average of 15°C (59°F), and a maximum of 23°C (74°F). Precipitation decreases to 107 mm (4.2 in) over just 10 days, while humidity increases to 83%. For more detailed insights on October weather, you can check Koper weather in October.
In comparing the weather of May and November, May offers milder temperatures, with a minimum of 7°C (46°F) and a pleasant average of 17°C (63°F), reaching a maximum of 27°C (81°F). In contrast, November brings cooler conditions, with temperatures dipping to a minimum of 1°C (34°F) and an average of just 11°C (52°F), peaking at 20°C (68°F). While May experiences approximately 142 mm (5.6 in) of precipitation over 17 days, November sees a bit more rain at 176 mm (6.9 in) but covers it in fewer days, with only 12 rainy days. Additionally, November's humidity is notably higher at 89%, compared to May’s 70%. For more details, see Koper weather in November.
May and December present contrasting weather patterns, highlighting the transition from spring to winter. In May, temperatures are generally milder, with averages around 17°C (63°F) and highs reaching up to 27°C (81°F), making it a pleasant month for outdoor activities. However, it also sees considerable precipitation, totaling 142 mm (5.6 in) over 17 days, with a humidity level of 70%.
In contrast, December experiences much cooler temperatures, with averages dropping to 7°C (44°F) and maximums only reaching 15°C (60°F). While December has slightly higher total precipitation at 150 mm (5.9 in), it occurs over fewer days (12), resulting in a more humid atmosphere at 88%. For a detailed overview of December weather specifics, you can check Koper weather in December.
As May unfolds in Koper, temperatures begin to rise significantly, offering a refreshing departure from the cooler months. With higher averages and occasional peaks reaching up to 27°C, residents and visitors can enjoy the warmth, although the lingering humidity at 70% introduces a muggy twist. While May does see a notable amount of rainfall, with about 17 days marked by precipitation, the overall climate is a vibrant transition into summer, contrasting sharply with the chill of earlier months. For a deeper understanding of Koper's weather patterns, visit Koper Climate.