September Weather in Piraeus, Greece

Last updated: August 21, 2025

September in Piraeus, Greece offers a delightful transition from summer to autumn. With maximum temperatures reaching 37°C (98°F) and an average of 24°C (76°F), the weather remains warm and inviting. Nights are pleasantly cooler, dipping to a minimum of 13°C (55°F). While the month sees only 17 mm (0.7 in) of precipitation over just two days, humidity levels hover around 65%, adding a subtle warmth to the atmosphere. This blend of conditions creates an ideal setting for enjoying the vibrant city and its stunning coastal views.

September Temperature in Piraeus

As summer transitions to fall, September in Piraeus, Greece showcases a delightful blend of warmth and refreshing breezes. With temperatures starting at a comfortable 13°C (55°F) and peaking at a toasty 37°C (98°F), the month averages around 24°C (76°F), offering an ideal atmosphere for outdoor activities and explorations. This noticeable warmth is a gentle reminder of the heat experienced in the peak summer months of July and August, yet it allows for more pleasant evenings and cooler breezes. As days become shorter, September's temperatures provide a seamless bridge to the milder days of October. It's a perfect time to experience the vibrant culture and scenic beauty of Piraeus while enjoying the lingering warmth of late summer.

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

The chart illustrates September temperature patterns in Piraeus, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Piraeus, 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).
JanFebMarAprMayJunJulAugSepOctNovDec485154606977838376665952
Data source: Temperature data for Piraeus generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Piraeus

September in Piraeus, Greece, marks a transition as summer wanes, bringing a modest precipitation amount of 17 mm (0.7 in) over just two days. Compared to the preceding months, where rainfall was nearly nonexistent in July and August, this slight uptick offers a refreshing change. While summer basks in long, dry stretches, the autumn months start to hint at the wetter season to come, with October ramping up precipitation to 30 mm (1.2 in) as the city prepares for the imminent rainy season. Despite September’s limited rainfall, the gradual shift sets the tone for a more balanced climate as the year progresses, bridging the gap between the arid summer and the rainy autumn.

September Precipitation Trends in Piraeus

The chart displays monthly precipitation patterns in Piraeus, 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 Piraeus, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec5748394223339417304866
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

September Humidity in Piraeus

In Piraeus, Greece, September marks a noticeable shift in humidity, settling at 65%. This drop follows a series of summer months where humidity levels reached their lowest, peaking in August at just 63%. As the summer heat begins to wane, September experiences a gradual increase in moisture, while still remaining relatively comfortable compared to the rest of the year. Overall, the humidity levels in Piraeus showcase a consistent pattern, peaking in the winter months with January and December at 76%, while the summer months enjoy a trend of declining humidity, culminating in the refreshing yet slightly more humid atmosphere of early autumn. This transition sets the stage for the mild and enjoyable fall weather that follows.

September Average Humidity in Piraeus

This chart illustrates the average monthly humidity levels in Piraeus, 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 Piraeus is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec76%75%74%75%77%72%68%63%65%72%75%76%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Piraeus

In September, Piraeus, Greece, experiences a UV Index of 8, indicating a very high exposure category, which means sun protection is essential during this time. This marks a slight decline from the peak summer months of June through August, where the UV Index remained consistently at 10. However, with a burn time of just 15 minutes, it’s crucial to remain vigilant even as the days grow shorter and temperatures begin to cool. This seasonal pattern shows a gradual shift from the intense UV rays of summer to more moderate levels in fall, as evidenced by the UV Index dropping to 7 in October. To plan your outdoor activities safely, keep an eye on the current UV Index levels in Piraeus by visiting Piraeus UV Index.

Maximum UV Index Levels in Piraeus for September

The chart shows the monthly maximum UV Index (UVI) for Piraeus 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 Piraeus typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec3468101010108743
Data source: Piraeus 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 Piraeus

As summer gently fades into autumn, September in Piraeus, Greece continues to bask in the sun's warm embrace, offering a delightful 346 hours of sunshine. This month showcases a notable transition, with daylight hours retreating from the peak of 423 hours seen in July. The sunlight begins to soften, yet remains inviting, hinting at a blend of lingering summer warmth and the fresh air of fall. This pattern reflects a broader trend of gradually diminishing sunshine as the year progresses, where each month leading into autumn brings fewer daylight hours, yet September holds onto enough brightness to keep the spirit of summer alive just a little longer.

Monthly Sunshine Duration in Piraeus: September Highlighted

The September sunshine duration represents the total number of hours Piraeus 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.
JanFebMarAprMayJunJulAugSepOctNovDec200h252h328h346h398h409h423h396h346h313h261h250h
Data source: Piraeus September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Piraeus During September

As the summer sun begins to wane, September in Piraeus, Greece, still boasts a promising 77% chance of sunny weather. This figure reflects a trend of delightful warmth, following the peak sunshine months of July and August, which enjoy an impressive 94% and 95% chance, respectively. While the likelihood of sun does dip slightly in the fall, September retains a vibrant glow, making it an ideal time for outdoor activities and exploration before the cooler autumn temperatures settle in. With a substantial chance of clear skies, visitors can savor the lingering warmth of summer while basking in the beautiful coastal scenery Piraeus has to offer.

Percentage of Sunny Days in September in Piraeus

The chart illustrates the percentage of sunny days in Piraeus 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 Piraeus experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec45%58%57%55%70%71%94%95%77%57%40%51%
Data source: Piraeus September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Piraeus in September

As summer wanes, September in Piraeus, Greece, sees a gentle decline in daylight, with the sun gracing the skies for about 12 hours. This month marks a transition from the long, sun-filled days of June, July, and August, which each enjoyed a maximum of 14 hours of daylight. While September still benefits from more light than the winter months, it signals the onset of cooler days ahead, leading to a gradual retreat into the shorter daylight hours of October and November. The rich tapestry of changing daylight not only influences the rhythm of daily life but also adds to the allure of Piraeus, inviting both locals and visitors to savor the lingering warmth of summer before autumn fully sets in.

Average Daylight Hours in Piraeus for September

The chart illustrates the variation in daylight duration in Piraeus throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 50m10h 46m11h 58m13h 11m14h 14m14h 44m14h 28m13h 33m12h 23m11h 10m10h 6m9h 33m
Data source: Piraeus daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Piraeus

In September, the winds in Piraeus, Greece, whistle at a pleasant average of 3.0 m/s (7 mph), marking a gentle resurgence as summer draws to a close. This month, while not the windiest, maintains a steady flow reminiscent of the earlier summer months, particularly July, which boasts the highest average at 3.1 m/s (7 mph). The transition from the languid breezes of June and May reveals a pattern of revitalization, suggesting that September serves as a bridge between the warm days of summer and the cooler embrace of autumn. As October follows closely with a similar wind speed, the coastal atmosphere remains charged with a refreshing vitality, setting the stage for the scenic beauty and cultural vibrancy that this seaside town is known for. With winter on the horizon, the wind's playful dance lingers yet, inviting locals and visitors alike to revel in the breezy charm of Piraeus.

Average September Wind Speed in Piraeus

The chart displays monthly wind speed patterns in Piraeus, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.23.02.92.62.41.83.12.73.0 m/s3.13.03.5
Data source: Piraeus September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Piraeus Compares to Other Months

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

September and January present strikingly different weather patterns. In September, temperatures range from a mild 13°C (55°F) at night to a warm 37°C (98°F) during the day, accompanied by relatively low precipitation of 17 mm (0.7 in) over just two days, and a humidity level of 65%. In contrast, January experiences much cooler temperatures, with a minimum of -4°C (25°F) and a maximum of 22°C (72°F), along with significantly higher precipitation of 57 mm (2.2 in) over seven days, resulting in a humidity level of 76%. This comparison highlights the transition from the warm, dry conditions of late summer to the cold, wetter winter months. For more information about January weather in Piraeus, visit Piraeus weather in January.

September and February present contrasting weather conditions. In September, temperatures are warmer, with a minimum of 13°C (55°F) and an average of 24°C (76°F), peaking at a scorching 37°C (98°F). The month experiences relatively low precipitation, only 17 mm (0.7 in) over just 2 days, and humidity is moderate at 65%. In contrast, February sees cooler temperatures, with a minimum of 0°C (32°F) and an average of 10°C (51°F), while the maximum only reaches 20°C (68°F). This month also experiences more significant rainfall, with 48 mm (1.9 in) spread over 8 days, coupled with higher humidity at 75%. For a closer look at February weather conditions, you can visit Piraeus weather in February.

September and March exhibit significantly different weather patterns. In September, temperatures can soar to a maximum of 37°C (98°F), with an average temperature of 24°C (76°F), while March sees much cooler temperatures, peaking at 23°C (74°F) and averaging just 12°C (54°F). Additionally, September experiences minimal rainfall, with only 17 mm (0.7 in) over just 2 days, contrasting sharply with March, which receives 39 mm (1.5 in) of precipitation spread over 5 days. Humidity levels also differ, with September at 65% and March higher at 74%. For more detailed insights, check out Piraeus weather in March.

September and April present distinctly different weather patterns. In September, temperatures range from a comfortable minimum of 13°C (55°F) to a sweltering maximum of 37°C (98°F), averaging around 24°C (76°F). The precipitation is relatively low at 17 mm (0.7 in), occurring over just two days, and the humidity sits at 65%. In contrast, April experiences cooler temperatures, with a minimum of 4°C (40°F) and a maximum of 29°C (85°F), resulting in an average of just 15°C (60°F). This month sees more precipitation, totaling 42 mm (1.6 in) over five days, and higher humidity at 75%. For more detailed insights on April weather, visit Piraeus weather in April.

September and May present distinct weather patterns, showcasing the transition between summer and autumn. In September, temperatures range from a minimum of 13°C (55°F) to a maximum of 37°C (98°F), with an average of 24°C (76°F). The month typically experiences low precipitation, averaging just 17 mm (0.7 in) over 2 days, along with a moderate humidity of 65%. In contrast, May features slightly cooler temperatures, with a minimum of 10°C (51°F) and a maximum of 36°C (97°F), averaging 21°C (70°F). Precipitation in May is higher at 23 mm (0.9 in) spread over 4 days, and humidity is notably higher at 77%. For more detailed insights, check out Piraeus weather in May.

In comparing the weather in September and June, September generally offers slightly milder conditions with an average temperature of 24°C (76°F) compared to June's average of 25°C (77°F). Both months start with minimum temperatures around 13°C, but June can reach a higher maximum of 38°C (101°F), while September peaks at 37°C (98°F). Precipitation is more frequent in June, averaging 33 mm over five days, compared to September's lighter rains, which total 17 mm over just two days. Additionally, humidity is higher in June at 71%, versus 65% in September, contributing to a more muggy feel during the hotter month. For more detailed information, check Piraeus weather in June.

In July, the weather is typically hotter with average temperatures reaching 28°C (83°F), peaking at a maximum of 42°C (108°F). The month experiences slightly lower precipitation at 9 mm (0.4 in) over just 2 days, and humidity levels are a touch higher at 68%. In contrast, September sees a decrease in both maximum temperatures, which can rise to 37°C (98°F), and averages settling at a cooler 24°C (76°F). The precipitation remains minimal at 17 mm (0.7 in) over the same 2 days, coupled with 65% humidity. For a detailed look at the July conditions, you can check out Piraeus weather in July.

In comparing the weather of September and August, we see a notable shift in temperatures and precipitation patterns. September shows a minimum temperature of 13°C (55°F), an average of 24°C (76°F), and a maximum of 37°C (98°F), indicating a significant drop from August's warmer averages, which range from a minimum of 19°C (66°F) to an average of 28°C (83°F) and peak at a scorching 43°C (109°F). Although September experiences slightly more precipitation at 17 mm (0.7 in) over 2 days, August remains drier with just 4 mm (0.2 in) and no recorded rainy days. Humidity levels are also relatively consistent, with September at 65% compared to August’s 63%. For more detailed information about August weather, you can refer to Piraeus weather in August.

September's weather typically features warmer conditions with average temperatures reaching 24°C (76°F) and maximum highs soaring up to 37°C (98°F). In contrast, October sees cooler temperatures, with a drop in the average to 19°C (66°F) and maximums peaking at 31°C (89°F). While September experiences relatively low rainfall of 17 mm over just 2 days, October brings increased precipitation at 30 mm over 4 days, and a rise in humidity levels from 65% in September to 72% in October. For more detailed insights into October's weather, visit Piraeus weather in October.

In September, temperatures are warm, with a minimum of 13°C (55°F) and an average high of 24°C (76°F), reaching up to 37°C (98°F) on particularly hot days. The month sees relatively low precipitation, averaging only 17 mm (0.7 in) over just 2 days, and humidity levels at 65%. In contrast, November experiences much cooler weather, with minimum temperatures dropping to 4°C (39°F) and average highs around 15°C (59°F), peaking at 25°C (78°F). Precipitation increases significantly, totaling 48 mm (1.9 in) spread over 7 days, and humidity rises to 75%. This shift highlights the transition from warm, dry days in September to cooler, wetter conditions in November. For more details on November weather, you can check Piraeus weather in November.

In September, temperatures are notably warmer, with a minimum of 13°C (55°F) and an average high reaching 37°C (98°F), while experiencing relatively low precipitation of just 17 mm (0.7 in) over only 2 days. In contrast, December brings a significant drop in temperatures, with a minimum of 1°C (34°F) and an average high of 21°C (70°F). Precipitation increases to 66 mm (2.6 in) spread across 9 days, resulting in a higher humidity level of 76%. For a more detailed look at the weather during this month, visit Piraeus weather in December.

Compare Piraeus's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Piraeus

September in Piraeus offers a delightful transition from the summer heat, with milder temperatures that create a more comfortable atmosphere for outdoor activities. While the city experiences a maximum peak of 37°C, the average temperature settles around a pleasant 24°C, providing a welcome reprieve from the sweltering days of July and August. With only two days of rain and a relatively low precipitation total, the month remains largely dry, allowing ample opportunities to explore the beautiful coastal scenery. Additionally, the humidity level of 65% adds to the comfortable feel, making September an ideal time for both locals and visitors. For a detailed overview of Piraeus' climate, check out Piraeus Climate.