Last updated: August 21, 2025
In September, Mostar, Bosnia and Herzegovina, showcases a warm climate with maximum temperatures reaching up to 33°C (91°F) and an average of 19°C (67°F). Visitors can expect a pleasant blend of sunshine and occasional rainfall, with precipitation amounting to 107 mm (4.2 in) over approximately 9 days of the month. The humidity level sits around 65%, contributing to a comfortable yet vibrant atmosphere, perfect for exploring this historical city. Whether you’re wandering through its famous streets or enjoying the local cuisine, September is an inviting time to experience Mostar’s charm.
September in Mostar, Bosnia and Herzegovina marks a transition into the crisp embrace of autumn, where temperatures begin to cool but still retain a touch of summer's warmth. With minimums averaging around 4°C (39°F) and reaching as high as 33°C (91°F), the month offers a delightful range for both early hikers and leisurely strollers. The average temperature settles at a pleasant 19°C (67°F), making it an ideal time for outdoor adventures. As the sweltering heat of August fades, September invites visitors to experience Mostar's stunning landscapes against a backdrop of comfortably mild weather, signifying a perfect balance between the lingering warmth of summer and the refreshing chill of autumn.
September in Mostar, Bosnia and Herzegovina, marks a transitional period in the weather, with precipitation amount reaching 107 mm (4.2 in) over 9 rainy days. As summer's dry spell wanes, this month's rainfall is a significant increase compared to the drier summer months of July and August, which received only 41 mm (1.6 in) and 54 mm (2.1 in) respectively. Interestingly, September's precipitation is comparable to the spring months, with March and May seeing similar amounts, hinting at a shift towards wetter conditions as the region heads into autumn. This slight uptick in rainfall not only refreshes the landscape but also sets the stage for the heavier downpours characteristic of the approaching winter months, where monthly totals surge to 251 mm (9.9 in) in November and 248 mm (9.8 in) in December.
In Mostar, Bosnia and Herzegovina, September marks a noticeable shift in humidity levels as summer draws to a close. With an average humidity of 65%, the city experiences a slight uptick from the drier months of July and August, which recorded just 59% and 53%, respectively. This increase in humidity signals the arrival of autumn, bridging the gap between the lush, vibrant summer and the wetter, cooler months to follow. Notably, the trend shows a gradual rise in humidity leading into the fall, reflecting a dynamic climate that transitions from relatively dry to more saturated conditions, culminating in the significantly higher humidity of 78% in October. As September unfolds, Mostar's atmosphere transforms, inviting a refreshing reprieve from the summer heat while hinting at the seasonal changes ahead.
As September arrives in Mostar, Bosnia and Herzegovina, the UV Index reflects a transition from the intense summer months, dipping to a high level of 7. This marks a gradual decrease from the very high levels reached in July and August, where outdoor enthusiasts enjoyed 15-minute burn times under the sun. In September, the sun still shines brightly, allowing for a longer burn time of 25 minutes before protective measures become essential. While visitors can relish the lingering warmth of late summer, it's crucial to remain vigilant about sun safety. With October on the horizon, the UV Index will continue its downward trend. For more detailed information on UV levels throughout the year, check out Mostar UV Index.
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September in Mostar, Bosnia and Herzegovina, offers a delightful transition into autumn, boasting an impressive 345 hours of sunshine. This marks a gradual decline from the sun-drenched peak of summer, with July shining the brightest at 435 hours. The month bridges the vibrant days of August and the cooler, cloudier October, which sees a decrease to 313 hours. As the warm glow of summer wanes, September’s sunshine still provides ample opportunity for outdoor exploration, allowing visitors to revel in the stunning landscapes and historic charm of Mostar before the shorter days set in. This sweet spot of sunshine, while slightly less than the bustling summer months, underscores the city's allure throughout the year.
As September rolls in, Mostar enjoys a notable transition in weather, with a 59% chance of sunny days. This month often marks the tail end of summer's warmth, as the sunshine lingers before autumn takes hold. Comparing September's sunshine probability to the summer months, which boast a peak of 73% in August, it's clear that the sun is still prevalent, though slightly less intense. However, with the drop in temperatures here, September remains a delightful period for outdoor activities, allowing residents and visitors alike to revel in the city's stunning landscapes under partly sunny skies. This favorable weather trend makes September an ideal time to experience Mostar's charm before the clouds start to gather in the fall.
As summer wanes in Mostar, September brings a gentle shift in daylight duration, offering about 12 hours of daylight—a subtle decline from the sun-drenched days of June and July that reached their peak at 15 hours. This transitional month mirrors the gradual retreat of summer's warmth, as the city begins to embrace the cooler hues of autumn. Unlike the early months of the year, where daylight starts at just 9 hours in January, September's abundance still allows for ample opportunities to explore Mostar's stunning landscapes and rich history before the daylight diminishes further in October. This rhythm of light serves as a beautiful reminder of the ever-changing seasons in this enchanting region of Bosnia and Herzegovina.
As September arrives in Mostar, Bosnia and Herzegovina, the gentle breeze begins to soften, with average wind speeds dipping to 1.7 m/s (4 mph). This marks a continuation of the trend witnessed during the summer months, where winds have gradually decreased, reaching their calmest during this transitional phase of the year. While January to May showcased a consistent 2.1 to 2.2 m/s comfort level, the midsummer months of June through August saw an even more subdued atmosphere. The September winds, though gentler, create an inviting ambiance, perfect for enjoying the picturesque views of the old town and the iconic Stari Most bridge. As fall approaches, the slight drop in wind speed not only signals a change in the season but also invites reflection and tranquility amidst Mostar's stunning landscapes.
Weather in Mostar varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Mostar, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather in Mostar offers a warm embrace with average temperatures reaching 19°C (67°F), occasionally peaking at a comfortable 33°C (91°F). This month sees a moderate amount of precipitation at 107 mm (4.2 in) over about 9 rainy days, accompanied by a humidity level of 65% that adds to the warmth. In stark contrast, January brings a chill with temperatures averaging just 3°C (37°F) and dipping as low as -13°C (8°F). This winter month experiences slightly higher precipitation at 112 mm (4.4 in) spread over 11 days, alongside a much higher humidity of 88%, which can make the cold feel even more penetrating. For a closer look at January weather, visit Mostar weather in January.
September and February present starkly contrasting weather conditions. In September, temperatures range from a pleasant minimum of 4°C (39°F) to a warm maximum of 33°C (91°F), with an average of 19°C (67°F). The month sees about 107 mm (4.2 in) of precipitation over nine days, along with a moderate humidity level of 65%. Conversely, February is much colder, with temperatures dipping to a minimum of -9°C (17°F) and reaching a maximum of 21°C (71°F), averaging just 6°C (43°F). This month is wetter, receiving 151 mm (5.9 in) of precipitation spread over 11 days, and higher humidity at 82%. For more detailed insights into February weather, check out Mostar weather in February.
In comparing the weather between September and March, we notice some stark contrasts. September typically sees milder temperatures, with averages around 19°C (67°F) and maximums reaching up to 33°C (91°F), while March is much cooler, averaging only 8°C (46°F) and ranging from a minimum of -8°C (17°F) to a maximum of 22°C (73°F). Precipitation is also notable in both months, with September receiving about 107 mm (4.2 in) over 9 days, whereas March experiences slightly higher precipitation at 141 mm (5.5 in) across 11 days. Additionally, humidity levels are higher in March at 79%, compared to September's 65%. For more detailed information about March weather, you can visit Mostar weather in March.
When comparing the weather in September and April, we see notable differences in temperature and precipitation. September typically boasts warmer temperatures, with a minimum of 4°C (39°F), an average of 19°C (67°F), and a maximum of 33°C (91°F). In contrast, April experiences cooler temperatures, ranging from a minimum of -4°C (25°F) to a maximum of 28°C (82°F), with an average of 12°C (53°F). Both months experience significant rainfall, but April is slightly wetter, with 116 mm (4.6 in) over 11 days compared to September's 107 mm (4.2 in) across 9 days. Additionally, April tends to be more humid, with levels reaching 75% compared to September's 65%. For more detailed information on April weather, you can check Mostar weather in April.
When comparing the weather in September and May, we see some notable differences. September typically has warmer average temperatures, ranging from a minimum of 4°C (39°F) to a maximum of 33°C (91°F), while May offers slightly cooler conditions, with temperatures ranging from a minimum of 1°C (34°F) to a maximum of 30°C (87°F). Precipitation is more frequent in May, occurring on about 16 days and totaling 132 mm (5.2 in), compared to September's 9 days of rain and 107 mm (4.2 in). Additionally, humidity levels are higher in May at 74%, compared to September's 65%. For more detailed information, you can visit Mostar weather in May.
Comparing the weather in September to that of June reveals notable differences in temperature and precipitation patterns. In September, the minimum temperature dips to 4°C (39°F), while June starts at a relatively warmer 7°C (45°F). The average temperature in June is slightly higher at 21°C (71°F) compared to September's average of 19°C (67°F). However, September offers a wider range, reaching a maximum of 33°C (91°F), while June can peak at a scorching 37°C (98°F).
Precipitation levels also vary between the two months; September experiences 107 mm (4.2 in) of rainfall over 9 days, indicating a wetter month, while June receives a lesser 69 mm (2.7 in) across 11 days. Humidity remains relatively stable, with September at 65% and June at 66%, creating a consistently muggy atmosphere.
For more detailed insight into June weather, check out Mostar weather in June.
In comparing the weather of September and July, we can see distinct differences in temperature and precipitation patterns. September experiences a wider temperature range, with minimums dropping to 4°C (39°F) and maximums reaching up to 33°C (91°F), resulting in an average temperature of 19°C (67°F). In contrast, July is notably warmer, with minimums at 11°C (53°F) and maximums soaring to 38°C (101°F), leading to a higher average of 24°C (76°F). Moreover, September sees significantly more precipitation, totaling 107 mm (4.2 in) over 9 days, while July is relatively dry with only 41 mm (1.6 in) of rainfall across 5 days. The humidity in September is also higher at 65% compared to July's 59%. For more details on July weather, you can visit Mostar weather in July.
Comparing the weather between September and August, September brings a notable shift in temperature and humidity. The average temperature in September is cooler at 19°C (67°F), with a minimum of 4°C (39°F) and a maximum of 33°C (91°F). In contrast, August is significantly warmer, featuring an average temperature of 25°C (77°F) and a maximum that reaches up to 41°C (105°F). Additionally, September experiences more precipitation, accumulating 107 mm (4.2 in) over 9 days, while August has only 54 mm (2.1 in) across 7 days. Humidity also rises in September to 65%, compared to the drier August average of 53%. For a closer look at August weather specifics, you can visit Mostar weather in August.
September and October show a notable shift in weather patterns. September experiences warmer temperatures, with a minimum of 4°C (39°F) and an average of 19°C (67°F), peaking at a high of 33°C (91°F), while October cools down significantly, featuring a minimum of 1°C (34°F) and an average of 14°C (57°F), with a maximum of 27°C (80°F). Additionally, October sees increased precipitation, totaling 140 mm (5.5 in) over 10 days, compared to September’s 107 mm (4.2 in) across 9 days. The humidity also rises from 65% in September to 78% in October, contributing to a more damp and chillier atmosphere. For more detailed information, you can check Mostar weather in October.
September weather is characterized by warmer temperatures, with an average of 19°C (67°F) and maximums reaching up to 33°C (91°F). It experiences relatively low precipitation of 107 mm (4.2 in) over about 9 days, accompanied by a moderate humidity level of 65%. In contrast, November sees a significant drop in temperatures, with averages around 10°C (50°F) and minimums plummeting to -3°C (26°F). The month also experiences a marked increase in precipitation, totaling 251 mm (9.9 in) over 12 days, and higher humidity levels at 85%. For more detailed insights, you can visit Mostar weather in November.
September and December present striking contrasts in weather conditions. September features a much warmer climate, with temperatures ranging from a minimum of 4°C (39°F) to a maximum of 33°C (91°F) and an average of 19°C (67°F). In contrast, December sees significantly colder temperatures, with a minimum of -7°C (19°F) and an average of just 5°C (42°F), peaking at 16°C (62°F). Additionally, December experiences nearly double the precipitation of September, with 248 mm (9.8 in) over 15 days compared to September's 107 mm (4.2 in) over 9 days. The humidity also rises in December to 86%, overshadowing September's 65%. For more detailed insights, check out Mostar weather in December.
As summer gradually transitions to autumn, September in Mostar offers a delightful respite from the sweltering heat of the preceding months. While daytime temperatures can still reach comfortably warm highs, the evenings start to feel noticeably cooler, hinting at the approaching fall. This month becomes a time of increased rainfall, as nine days of precipitation contribute to a lush landscape, with humidity remaining at a moderate level. The overall climate provides an invigorating balance between warmth and freshness, making it a perfect opportunity for exploring the stunning natural scenery. For a more detailed understanding, visit Mostar Climate.