September Weather in Constanta, Romania

Last updated: August 27, 2025

September in Constanta, Romania, offers a delightful transition into autumn, with average temperatures hovering around 21°C (70°F). Daily highs can reach a pleasant 28°C (83°F), while nights cool off to about 11°C (52°F), making it ideal for outdoor activities. With only 21 mm (0.8 in) of rainfall spread across 3 days, the month is generally dry, allowing for ample sunshine. Humidity levels at around 61% contribute to a comfortable atmosphere, perfect for exploring coastal attractions or enjoying the vibrant local culture.

September Temperature in Constanta

In September, Constanta, Romania, experiences a delightful transition as summer begins to wane and autumn approaches. With temperatures ranging from a comfortable 11°C (52°F) at night to a warm 28°C (83°F) during the day, this month strikes a perfect balance, offering enjoyable weather for both locals and visitors. The average temperature sits at a pleasant 21°C (70°F), making it one of the most inviting times of the year to explore the coastal beauty of the Black Sea. As the heat of summer recedes and the air takes on a crisp freshness, September is an ideal opportunity to savor outdoor activities and bask in the golden hues of early autumn.

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

The chart illustrates September temperature patterns in Constanta, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Constanta, 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).
JanFebMarAprMayJunJulAugSepOctNovDec384043506171757669605144
Data source: Temperature data for Constanta 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 Constanta

September in Constanta, Romania, marks the transition from summer's dry spell to the more humid autumn months. With only 21 mm (0.8 in) of rain falling over a mere 3 days, September showcases a marked decrease in precipitation compared to the preceding summer, notably August’s minimal 11 mm (0.4 in). This shift suggests that while summer is gradually giving way to autumn, the weather remains relatively stable with infrequent, light showers. As the year progresses, precipitation tends to increase, with October bringing a rise back up to 50 mm (2.0 in), hinting at a more robust wet season ahead. The patterns illustrate how Constanta experiences varying precipitation levels throughout the year, with September serving as a brief interlude before the wetter months emerge.

September Precipitation Trends in Constanta

The chart displays monthly precipitation patterns in Constanta, 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 Constanta, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec504244283067501121505468
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Constanta

September in Constanta, Romania, marks a subtle shift in humidity as summer transitions into autumn. With a humidity level of 61%, it reflects a slight increase from the drier months of July and August, which saw lows of 65% and 53%, respectively. This uptick hints at the approaching fall, as moisture begins to creep back into the coastal air. Interestingly, the trend of decreasing humidity from January's high of 87% reaches its low in August, but the return to 61% in September suggests a gradual reintroduction of the wetter conditions typical of the season. As the month progresses, residents can expect a refreshing blend of warm days and cooler evenings, with the evolving humidity serving as a reminder of the changing seasons.

September Average Humidity in Constanta

This chart illustrates the average monthly humidity levels in Constanta, 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 Constanta is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec87%83%80%76%73%68%65%53%61%77%85%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Constanta

As the warm days of summer fade into autumn, September in Constanta, Romania still offers a high UV Index of 7, categorizing exposure as high with a burn time of about 25 minutes. This month marks a transition from the very high levels of UV radiation experienced in the summer, where consistently high readings of 8 and 9 demanded caution and protection. As the days begin to shorten, the gradual decline in UV intensity signifies that while outdoor activities remain enjoyable, it's still important to stay vigilant about sun protection during this transitional phase. For a more detailed overview of UV exposure trends throughout the year, visit the Constanta UV Index.

Maximum UV Index Levels in Constanta for September

The chart shows the monthly maximum UV Index (UVI) for Constanta 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 Constanta typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec235789987532
Data source: Constanta 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 Constanta

In September, Constanta, Romania, basks in a delightful 343 hours of sunshine, making it a perfect transition month that bridges the vibrant summer and the cooler autumn. Following the peak of 434 hours in July, the daylight gradually begins to wane but still offers plenty of warmth and bright days. This trend reflects the region’s climatic shift, where sunshine hours taper off from the sun-soaked summer but remain inviting in early autumn. As the month progresses, locals and visitors alike can relish the crisp, clear days that September provides, perfect for exploring the historic coastal city before the cooler months set in.

Monthly Sunshine Duration in Constanta: September Highlighted

The September sunshine duration represents the total number of hours Constanta 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.
JanFebMarAprMayJunJulAugSepOctNovDec158h229h301h353h408h417h434h407h343h292h214h194h
Data source: Constanta September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Constanta During September

September in Constanta, Romania, offers a promising chance of sunny weather, with about 60% likelihood of clear skies. As summer transitions into autumn, this month maintains a solid average of sunshine following the vibrant peaks of July and August, which boast remarkable probabilities of 77% and 75%, respectively. This substantial decrease from the summer months still positions September favorably compared to the chillier months ahead, where the sun's presence dwindles significantly, ranging from 33% in October to as low as 26% in January. Thus, September serves as a delightful bridge, allowing residents and visitors to relish the lingering warmth and outdoor enjoyment before the cooler days set in.

Percentage of Sunny Days in September in Constanta

The chart illustrates the percentage of sunny days in Constanta 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 Constanta experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec26%35%42%41%44%45%77%75%60%33%32%26%
Data source: Constanta September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Constanta in September

As summer transitions to autumn in Constanta, Romania, September marks a gentle decline in daylight, providing approximately 12 hours of sunlight each day. After basking in the long days of June and July, which boast the year’s peak at 15 hours, residents begin to notice a subtle shift as the evenings grow longer. Following August’s warm hues and 13 hours of daylight, September serves as a graceful bridge to fall, with its golden light gradually yielding to the shorter days ahead. This rhythm of daylight not only highlights the beauty of the changing seasons but also sets the stage for the cozy ambiance of autumn, inviting locals to savor the last sunlit days before the onset of winter’s early twilight.

Average Daylight Hours in Constanta for September

The chart illustrates the variation in daylight duration in Constanta throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 16m10h 27m11h 56m13h 28m14h 47m15h 27m15h 6m13h 56m12h 28m10h 56m9h 36m8h 54m
Data source: Constanta daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Constanta

In September, the winds in Constanta, Romania, begin to pick up a notch, with an average speed of 5.3 m/s (12 mph). This marks a slight increase from the summer months, where the winds averaged around 4.5 m/s (10 mph). As the summer heat wanes, September becomes a transitional month, hinting at the dynamic shifts that autumn will bring. Following this pattern, October sees an even more pronounced increase to 5.9 m/s (13 mph), setting the stage for the brisker days ahead. Overall, September's winds offer a refreshing change, inviting both locals and visitors to enjoy the coastal breezes that gently herald the onset of fall.

Average September Wind Speed in Constanta

The chart displays monthly wind speed patterns in Constanta, 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.
JanFebMarAprMayJunJulAugSepOctNovDec6.35.15.54.24.44.54.54.35.3 m/s5.95.16.7
Data source: Constanta September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Constanta Compares to Other Months

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

September and January present stark contrasts in weather. In September, temperatures typically range from a minimum of 11°C (52°F) to a comfortable maximum of 28°C (83°F), with an average of 21°C (70°F) and relatively low precipitation of 21 mm (0.8 in) over just 3 days, accompanied by a humidity level of 61%. In contrast, January feels much colder, with temperatures dropping to a minimum of -10°C (14°F) and only reaching a maximum of 14°C (57°F), averaging around 3°C (38°F). The month sees significantly more precipitation—50 mm (2.0 in) over 7 days—and higher humidity at 87%. For a closer look at February weather, visit Constanta weather in January.

September and February present starkly contrasting weather conditions. In September, temperatures range from a mild 11°C (52°F) at night to a warm 28°C (83°F) during the day, with an average of 21°C (70°F). This month experiences relatively low precipitation at 21 mm (0.8 in), spread over just three days, and a comfortable humidity level of 61%. In contrast, February sees much colder temperatures, with a minimum of -6°C (22°F) and a maximum of 15°C (59°F), averaging only 5°C (41°F). This winter month has higher precipitation of 42 mm (1.7 in) over seven days and a humidity level of 83%, making it feel considerably more damp and chilly. For more details on the February climate, check Constanta weather in February.

September and March exhibit significantly different weather patterns. In September, temperatures are much milder, ranging from a minimum of 11°C (52°F) to a maximum of 28°C (83°F), with an average of 21°C (70°F). The month is characterized by relatively low precipitation, with only 21 mm (0.8 in) over just 3 days and humidity levels around 61%. In contrast, March experiences cooler temperatures, with minimums plummeting down to -9°C (17°F) and maximums only reaching up to 16°C (61°F), averaging 6°C (43°F). Precipitation during March is considerably higher at 44 mm (1.7 in), spread across 8 days, and humidity levels rise to 80%. For more details on March weather, you can visit Constanta weather in March.

September and April present contrasting weather conditions. In September, temperatures range from a mild minimum of 11°C (52°F) to a warm maximum of 28°C (83°F), with an average of 21°C (70°F), making it generally more pleasant. Meanwhile, April is cooler, with temperatures dipping as low as 3°C (38°F) and averaging around 10°C (50°F), peaking at just 20°C (69°F). Additionally, April tends to be wetter, with precipitation reaching 28 mm (1.1 in) over six days compared to September's 21 mm (0.8 in) spread over just three days. Humidity also increases in April, sitting at 76% compared to September's 61%. For more specific information, you can visit Constanta weather in April.

September generally offers warmer temperatures compared to May, with averages reaching 21°C (70°F) and daytime highs around 28°C (83°F). In contrast, May has a cooler average of 16°C (61°F), with maximum temperatures peaking at 25°C (77°F). While September experiences less precipitation with only 21 mm (0.8 in) over just 3 days, May tends to be rainier, accumulating 30 mm (1.2 in) across 7 days. Additionally, May has higher humidity, averaging 73%, compared to September's 61%. For more details on May weather, you can visit Constanta weather in May.

In comparing the weather of September and June, both months exhibit similar average temperatures, with September registering a minimum of 11°C (52°F) and a maximum of 28°C (83°F), while June features a slightly warmer range, with temperatures from a minimum of 12°C (54°F) to a maximum of 29°C (84°F). September experiences significantly less precipitation, totaling only 21 mm (0.8 in) over just three days, compared to June's much wetter climate, which sees 67 mm (2.6 in) spread across ten days. Additionally, humidity levels are slightly lower in September at 61%, compared to June's 68%. For a more detailed overview of the weather in June, you can check Constanta weather in June.

September weather is characterized by milder temperatures and less humidity compared to July. While September sees average temperatures ranging from a minimum of 11°C (52°F) to a maximum of 28°C (83°F), July is warmer, with temperatures averaging between 17°C (62°F) and 31°C (87°F). Additionally, September has significantly lower precipitation at 21 mm (0.8 in) over 3 days, whereas July experiences more rainfall at 50 mm (2.0 in) over 6 days. This results in a drier feel in September despite the slightly lower humidity of 61%, compared to July's 65%. For a detailed look at July's weather, visit Constanta weather in July.

When comparing the weather in September to that of August, there are notable differences in temperature and humidity. September features cooler temperatures, with a minimum of 11°C (52°F) and an average of 21°C (70°F), whereas August tends to be warmer, with a minimum of 17°C (64°F) and an average of 25°C (77°F). Additionally, September experiences slightly more precipitation, totaling 21 mm (0.8 in) over three days, compared to August's 11 mm (0.4 in) under the same number of rainy days. The humidity in September is also higher at 61%, compared to 53% in August, contributing to a different feel in the air as summer transitions into fall. For more details on August weather, you can visit Constanta weather in August.

September and October show a notable shift in weather patterns. September features milder temperatures, with minimums around 11°C (52°F) and maximums reaching 28°C (83°F), offering an average of 21°C (70°F), accompanied by moderate humidity levels of 61%. In contrast, October experiences cooler temperatures, with minimums dropping to 7°C (45°F) and average temperatures declining to 16°C (60°F); the maximum temperature caps at 24°C (76°F). Additionally, October sees a significant increase in precipitation, totaling 50 mm (2.0 in) over 5 days, compared to September's 21 mm (0.8 in) over just 3 days. This increase in humidity to 77% further emphasizes the shift to a wetter and cooler month. For more specific details, you can check Constanta weather in October.

September typically offers a warmer climate with average temperatures around 21°C (70°F), peaking at a comfortable 28°C (83°F). With minimal precipitation of only 21 mm (0.8 in) over just three days, the month is characterized by relatively moderate humidity at 61%. In contrast, November brings a significant chill, with average temperatures dropping to 11°C (51°F) and lows reaching -1°C (31°F). This month sees increased precipitation, totaling 54 mm (2.1 in) across nine days, alongside higher humidity levels at 85%. For more insights about November weather in Constanta, visit Constanta weather in November.

In September, the weather is notably mild, with temperatures ranging from a minimum of 11°C (52°F) to a maximum of 28°C (83°F), and an average of around 21°C (70°F). The month typically sees about 21 mm (0.8 in) of precipitation spread over three days, contributing to a comfortable humidity level of 61%. In contrast, December brings much colder weather, with temperatures dropping significantly, ranging from a minimum of -5°C (24°F) to a maximum of 16°C (61°F), and an average of only 7°C (44°F). This month is also wetter, with 68 mm (2.7 in) of precipitation occurring over 12 days, resulting in a higher humidity of 86%. For a detailed look at what to expect, you can check out Constanta weather in December.

Compare Constanta's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Constanta

As summer gracefully transitions into autumn, September in Constanta offers a delightful blend of warm days and cooler nights, making it distinct from the peak summer months. With average temperatures hovering around a comfortable 21°C (70°F) and maximums reaching 28°C (83°F), the weather encourages outdoor activities while the evenings bring a refreshing chill. Rainfall is minimal, with only a few days of precipitation, allowing visitors to bask in the sun without interruption. This month strikes a perfect balance, offering moderate humidity that enhances the pleasant coastal atmosphere. For those interested in the broader climate patterns, explore more at Constanta Climate.