September Weather in Seal Beach, United States

Last updated: February 24, 2025

In September, Seal Beach, United States, experiences a delightful blend of warm temperatures and dry conditions. With a maximum of 38°C (102°F) and an average temperature of 22°C (72°F), the month promises plenty of sunshine, while the minimum dips to a comfortable 15°C (58°F) during cooler nights. Remarkably, the region sees only 3 mm (0.1 in) of precipitation across 0 days, making it an ideal time for outdoor activities. The humidity level hovers around 68%, adding a touch of warmth to the coastal atmosphere, perfect for enjoying the beautiful beaches and vibrant local life.

September Temperature in Seal Beach

In September, Seal Beach experiences a pleasant transition from the summer heat, with temperatures ranging from a minimum of 15°C (58°F) to a peak of 38°C (102°F). The average temperature settles at a comfortable 22°C (72°F), making it ideal for beach activities and outdoor excursions. As the month progresses, the lingering warmth from the summer begins to ease, foreshadowing the cooler months ahead. This combination of mild mornings and warm afternoons reflects a unique trend in Seal Beach's climate, where late summer extends into early fall, providing residents and visitors alike with the perfect summer send-off under the Californian sun.

September Weather in Seal Beach: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Seal Beach, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec575759636467727372696357
Data source: Temperature data for Seal Beach 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 Seal Beach

In September, Seal Beach experiences an unusually dry spell, with just 3 mm (0.1 in) of precipitation recorded, matching the minimal rainfall seen in the summer months. Remarkably, this marks the first month of the year without any rainy days, reflecting a trend towards drier weather as the summer transitions into fall. Prior months, from January through August, showcased a clear decrease in rainfall, with peaks early in the year, while September's dryness signals a significant departure from the wetter seasons. As we approach the final months of the year, it's evident that Seal Beach blends periods of heavy rainfall with extended dry spells, creating a unique coastal climate.

September Precipitation Trends in Seal Beach

The chart displays monthly precipitation patterns in Seal Beach, 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.
JanFebMarAprMayJunJulAugSepOctNovDec6552552312432391868
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Seal Beach

As summer fades into autumn, September in Seal Beach showcases a decline in humidity, dropping to 68%. This marks a continuation of the downward trend initiated in August, where humidity reached its seasonal low of 69%. The overall pattern reveals a steady decrease in moisture levels as the year progresses, peaking in the colder months of January and February at 74% and 79% respectively. This gradual reduction not only signifies the shift toward cooler weather but also offers a more comfortable climate for outdoor activities. In fact, as the humidity settles lower each month, from July's 73% to September's 68%, residents and visitors alike can enjoy the crisp, refreshing air that accompanies the arrival of fall.

September Average Humidity in Seal Beach

This chart illustrates the average monthly humidity levels in Seal Beach, with September's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how September's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec74%79%75%71%70%72%73%69%68%67%68%71%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Seal Beach

In September, Seal Beach experiences a very high UV Index of 10, which is consistent with the peak summer months that also saw extreme levels. With a burn time of just 15 minutes, it’s essential for residents and visitors to take sun safety seriously as summer’s intensity lingers into early fall. This trend is indicative of a gradual decrease from the extreme levels recorded in July and August, yet the need for protection remains critical. As the month progresses, the UV Index will start to decline, but awareness and precautions are still key to enjoying outdoor activities safely. For more details and real-time updates, check out the Seal Beach UV Index.

Maximum UV Index Levels in Seal Beach for September

The chart shows the monthly maximum UV Index (UVI) for Seal Beach 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.
JanFebMarAprMayJunJulAugSepOctNovDec468101011111010754
Data source: Seal Beach 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 Seal Beach

As summer gracefully transitions into autumn, September in Seal Beach continues to bask in plentiful sunshine, boasting an impressive 316 hours of sunlight. This marks a noticeable decline from the sun-drenched days of July and August, which captured the peak of summer with 379 and 361 hours respectively. However, September still shines brighter than its early autumn counterparts, notably October, which records a lesser 293 hours. The month embodies a beautiful blend of warmth and mildness, providing locals and visitors alike with ample opportunity to savor the last rays of summer before the cooler months set in. As we move into October, the gradual tapering of sunshine is a gentle reminder of the changing seasons that define this charming beach community.

Monthly Sunshine Duration in Seal Beach: September Highlighted

The September sunshine duration represents the total number of hours Seal Beach 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.
JanFebMarAprMayJunJulAugSepOctNovDec190h236h290h318h350h366h379h361h316h293h256h226h
Data source: Seal Beach September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Seal Beach During September

September in Seal Beach boasts a *notable *68% chance of sunny weather, making it one of the sunniest months of the year. As summer transitions to fall, this month stands out with a slight uptick in sunshine compared to the preceding months, particularly May and April, which experience lower probabilities of clear skies. The trend shows a general increase in sunshine from the spring months, with August leading at 67%. Interestingly, the sunny disposition continues into October, maintaining a robust 65%. Overall, September serves as a perfect blend of warm days and clear skies, ideal for beachgoers and outdoor enthusiasts alike.

Percentage of Sunny Days in September in Seal Beach

The chart illustrates the percentage of sunny days in Seal Beach 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 Seal Beach experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec61%61%67%51%48%58%61%67%68%65%66%46%
Data source: Seal Beach September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Seal Beach in September

In September, Seal Beach enjoys about 12 hours of daylight, marking a transition from the extended summer days just experienced. As the summer months of June and July brought 14 hours of sunlight, the gradual decrease in daylight begins to set the stage for the approaching fall. This month also reflects a subtle shift in the seasonal rhythm, as the days shorten from the vibrancy of summer toward the more subdued light of autumn, ultimately leading to October's 11 hours. Collectively, the daylight pattern showcases a natural ebb and flow of the seasons, with each month contributing to the unique character of life in this coastal city.

Average Daylight Hours in Seal Beach for September

The chart illustrates the variation in daylight duration in Seal Beach throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 11m10h 58m11h 59m13h 2m13h 55m14h 20m14h 6m13h 20m12h 19m11h 17m10h 23m9h 56m
Data source: Seal Beach daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Seal Beach

As summer fades into autumn in Seal Beach, September brings a gentle sigh with an average wind speed of 2.3 m/s (5 mph), slightly lower than the preceding months. This modest breeze reflects a trend of gradually diminishing wind speeds as the year progresses, with peaks observed in the vibrant months of spring and early summer. In contrast to July’s 2.5 m/s, the September winds speak to a calming transition, heralding the arrival of cooler days ahead. As the coastal air begins to chill, the soft winds evoke a sense of serenity, inviting locals and visitors alike to enjoy the tranquil beauty of the beach.

Average September Wind Speed in Seal Beach

The chart displays monthly wind speed patterns in Seal Beach, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.42.42.62.82.82.82.52.42.3 m/s2.32.02.4
Data source: Seal Beach September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Seal Beach Compares to Other Months

The weather in Seal Beach changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Seal Beach and find detailed weather information for every month.

September and January present contrasting weather patterns. In September, temperatures range from a minimum of 15°C (58°F) to a scorching maximum of 38°C (102°F), with an average of 22°C (72°F) and virtually no precipitation, only 3 mm over the entire month. In contrast, January sees much cooler conditions, with temperatures dropping to a minimum of 5°C (41°F) and peaking at 29°C (85°F), averaging 14°C (57°F). This month also experiences significantly more rainfall, with 65 mm over five days, and a humidity level of 74%. For a closer look at the January climate, visit Seal Beach weather in January.

September and February exhibit stark contrasts in weather patterns. September typically boasts a warm climate, with average temperatures around 22°C (72°F) and maximums soaring to 38°C (102°F), coupled with minimal precipitation of just 3 mm (0.1 in) and an average humidity of 68%. In sharp contrast, February presents cooler conditions, with average temperatures dropping to 14°C (58°F) and a maximum of 30°C (85°F). Additionally, February is marked by higher precipitation levels, totaling 52 mm (2.0 in) over about 5 days, and increased humidity at 79%. For a closer look at February weather, you can visit Seal Beach weather in February.

In September, the weather is notably warmer and drier, with average temperatures around 22°C (72°F) and maximums reaching up to 38°C (102°F). Humidity levels are relatively high at 68%, but there is virtually no precipitation. In contrast, March brings cooler temperatures, with averages dropping to 15°C (60°F) and maximums around 27°C (81°F). This month experiences significantly more rainfall, totaling 55 mm (2.2 in) over eight days, and humidity increases slightly to 75%. For a detailed look at conditions, you can check Seal Beach weather in March.

When comparing the weather in September and April, notable differences emerge. September typically boasts warmer temperatures, with an average of 22°C (72°F) and a maximum reaching up to 38°C (102°F), while April experiences a cooler average of 17°C (63°F) and maxing out at 34°C (94°F). Additionally, September enjoys dry conditions with minimal precipitation (3 mm) and virtually no rainy days, contrasting sharply with April, which has a higher rainfall of 23 mm over two days. Humidity levels are relatively similar, with September at 68% and April slightly higher at 70%. For more details on April weather, you can visit Seal Beach weather in April.

In September, temperatures are notably warmer, with averages around 22°C (72°F) and maximums reaching up to 38°C (102°F), while May experiences cooler conditions, with average temperatures of 18°C (64°F) and maximums of 30°C (86°F). Additionally, September remains largely dry, boasting no days of precipitation and only 3 mm (0.1 in) of rain, whereas May sees more frequent rainfall, accumulating 12 mm (0.5 in) over three days. Humidity levels are comparable in both months, hovering around 68% in September and 70% in May, making for a somewhat humid atmosphere in each. For further details, check out Seal Beach weather in May.

In comparing the weather of September and June, we can see some notable differences. September typically enjoys warmer temperatures with a minimum of 15°C (58°F), an average of 22°C (72°F), and a maximum that can reach as high as 38°C (102°F). In contrast, June offers slightly cooler conditions, with a minimum of 14°C (57°F), an average of 20°C (68°F), and a maximum of 33°C (91°F). Both months experience minimal precipitation, with September receiving only 3 mm (0.1 in) and June slightly more at 4 mm (0.2 in), although neither has any rainy days. Humidity levels are comparable, with September at 68% and June slightly higher at 72%. For more on the specific weather details, you can check out Seal Beach weather in June.

In comparing the weather of September and July, we observe some similarities and slight variations. Both months feature average temperatures around 22°C (72°F), with maximum temperatures peaking at 38°C (102°F) in September and 39°C (103°F) in July. Interestingly, both months recorded minimal precipitation at just 3 mm (0.1 in) and experienced no rainy days. However, July is slightly more humid at 73%, compared to September's 68%. For a detailed look at July's climate, you can visit Seal Beach weather in July.

In September, the weather remains warm with minimum temperatures around 15°C (58°F) and average highs reaching up to 38°C (102°F), contrasting with August's milder maximum of 34°C (94°F). While both months experience minimal precipitation, September features slightly more rain with 3 mm (0.1 in) compared to August's 2 mm (0.1 in). Humidity levels are similar, with September at 68% and August at 69%. For a closer look at weather patterns, you can check out Seal Beach weather in August.

In September, temperatures tend to be warmer, with a minimum of 15°C (58°F) and an average of 22°C (72°F), peaking at a hot 38°C (102°F). This month also boasts dry conditions, with only 3 mm (0.1 in) of precipitation, recorded over no rainy days, and a humidity level of 68%. In contrast, October experiences cooler weather, with minimum temperatures dropping to 11°C (52°F) and an average of 20°C (69°F), while the maximum remains similar at 38°C (101°F). The month sees an increase in precipitation, totaling 9 mm (0.4 in) over 2 days, and a slightly lower humidity level of 67%. For more detailed information, you can check out Seal Beach weather in October.

In September, the weather is typically warm and dry, with average temperatures around 22°C (72°F) and maximums reaching up to 38°C (102°F), while experiencing virtually no rainfall. In contrast, November brings a noticeable drop in temperatures, with average highs around 17°C (63°F) and minimums dipping to 8°C (46°F). Additionally, November sees some precipitation, totaling 18 mm (0.7 in) over two days, which is a significant increase compared to September. Both months maintain a humidity level of 68%, but the overall feel of November is much cooler and more varied. For additional insights, you can check out Seal Beach weather in November.

In September, the weather is typically warm, with average temperatures around 22°C (72°F) and a maximum reaching up to 38°C (102°F). The month experiences little to no rainfall, with only 3 mm of total precipitation over no rainy days, resulting in a relatively humid atmosphere at 68%. In contrast, December heralds a much cooler climate, with average temperatures dropping to 14°C (58°F) and maximums capping at 27°C (82°F). This month is marked by increased rainfall, with 68 mm over five days, and a slightly elevated humidity of 71%. For more detailed insights on December weather, you can visit Seal Beach weather in December.

Compare Seal Beach's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Seal Beach

As summer gracefully transitions to autumn, September in Seal Beach showcases a delightful blend of warmth and relatively low precipitation, setting it apart from the wetter months that precede it. With maximum temperatures peaking at a toasty 38°C (102°F) and an average that settles comfortably around 22°C (72°F), visitors can revel in the sun-drenched days while enjoying pleasant evenings. The humidity hovers around 68%, providing a refreshing coastal feel without the stickiness typical of warmer periods. Ideal for outdoor activities and beach outings, September's dry spell—boasting just 3 mm of precipitation—makes it a standout month for those looking to soak up the sun. For more insights into how this month compares to the rest of the year, visit Seal Beach Climate.