September Weather in Long Beach, United States

Last updated: February 24, 2025

In September, Long Beach, United States, experiences a delightful blend of warm temperatures and humid conditions. With a maximum of 32°C (89°F) and a comfortable average of 25°C (78°F), the weather invites outdoor activities. The nights offer a refreshing respite, dipping to a minimum of 14°C (58°F). However, this month also sees significant precipitation, totaling 212 mm (8.4 in) over approximately 12 days, adding a touch of vitality to the landscape. With humidity levels hovering around a soothing 81%, September presents a unique and memorable climatic experience for residents and visitors alike.

September Temperature in Long Beach

In Long Beach, September marks a transition into warm and pleasant weather, with temperatures showcasing a comfortable range. With minimums around 14°C (58°F) and averages soaring to 25°C (78°F), it’s an ideal time for outdoor activities. The highs can reach a scorching 32°C (89°F), reminiscent of summer's peak, yet the evenings cool down enough to enjoy the refreshing ocean breeze. This month serves as a bridge from the heat of summer into the milder autumn temperatures, making it a delightful time for locals and visitors alike to soak in the sun before the cooler months approach.

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

The chart illustrates September temperature patterns in Long Beach, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec505457647277818077715954
Data source: Temperature data for Long Beach 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 Long Beach

In September, Long Beach experiences a notable peak in precipitation, with 212 mm (8.4 in) of rain accumulated over 12 days. This marks a continuation of the upward trend in rainfall from the preceding months, particularly after a significant increase in August. The transition from summer to fall is unmistakable, as September often ushers in a shift from the drier spells of late spring and summer to a wetter climate. Notably, while the number of rainy days slightly decreases from August's 21 days, the intensity of the rainfall sets September apart as one of the most precipitative months of the year, laying the groundwork for the anticipated autumn months ahead.

September Precipitation Trends in Long Beach

The chart displays monthly precipitation patterns in Long 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.
JanFebMarAprMayJunJulAugSepOctNovDec70108759510713816420421267104132
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Long Beach

In Long Beach, United States, September sees a slight dip in humidity, averaging 81%, mirroring the cozy feel of late summer while preparing for the shift into fall. The humidity during this month is comparable to that of August and slightly higher than that in May through July, creating a pleasantly warm atmosphere. Interestingly, this pattern reflects a gradual increase in humidity levels from the cooler months of January (83%) through April (78%), followed by a peak in November (82%) and the year's end with December (84%). As the summer warmth begins to wane, September's humidity strikes a balance, maintaining a comfortable coastal environment, perfect for enjoying the last lingering days of the season.

September Average Humidity in Long Beach

This chart illustrates the average monthly humidity levels in Long 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.
JanFebMarAprMayJunJulAugSepOctNovDec84%80%79%78%78%78%82%81%81%78%82%84%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Long Beach

In September, Long Beach experiences a UV Index of 9, categorizing it as very high and indicating a burn time of just 15 minutes without protection. This marks a slight decline from the peak of 11 seen over the summer months, yet remains significantly elevated. The trend reveals that as summer transitions into fall, the UV Index begins to wane, but care should still be taken; sunscreen and protective attire are essential to mitigate the risks associated with intense sun exposure. As you enjoy the warm September days, be mindful of the lingering strength of the sun, as the region prepares to shift to slightly lower UV levels in the upcoming months. For more detailed insights, check out the Long Beach UV Index.

Maximum UV Index Levels in Long Beach for September

The chart shows the monthly maximum UV Index (UVI) for Long 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.
JanFebMarAprMayJunJulAugSepOctNovDec47810111111119864
Data source: Long 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 Long Beach

As September rolls into Long Beach, the sunshine continues to grace the city with a generous 299 hours of warmth, perfectly capping off a vibrant summer. Following the sun-drenched heights of July and August, which boasted 339 and 320 hours respectively, September retains a commendable glow, though slightly dimmer as autumn whispers its arrival. Looking back, the gradual increase in daylight hours from January's modest 183 to May's sun-soaked 342 illustrates a seasonal optimism that many residents cherish. This trend hints at the allure of Long Beach as a destination where sunlight remains plentiful, fostering both relaxation and inspiration as summer transitions into fall. The spell of sunny days may wane with the approaching winter months, but the lingering warmth of September ensures that Long Beach remains a radiant jewel on the California coast.

Monthly Sunshine Duration in Long Beach: September Highlighted

The September sunshine duration represents the total number of hours Long 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.
JanFebMarAprMayJunJulAugSepOctNovDec183h210h279h311h342h321h339h320h299h296h240h212h
Data source: Long Beach September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Long Beach During September

In Long Beach, United States, September boasts a 55% chance of sunny weather, making it one of the more promising months for sunshine after the summer season. This month shows a notable increase in sunny days compared to summer, where the sun peaks at just 43% in July and drops even further in August to 37%. As the year progresses, the chance of sunny weather generally fluctuates, with April leading at 60% and November also reflecting a favorable 59%. September not only provides a delightful transition from the sweltering summer months but also sets the stage for a pleasant fall, blending the warm and sunny vibes that residents and visitors alike cherish. Overall, September stands as a charming time in Long Beach, promising more sun than the season's preceding months.

Percentage of Sunny Days in September in Long Beach

The chart illustrates the percentage of sunny days in Long 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 Long Beach experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec50%36%35%60%50%30%43%37%55%49%59%48%
Data source: Long Beach September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Long Beach in September

As summer transitions to fall in Long Beach, September brings a gentle decline in daylight, with the sun gracing the skies for approximately 12 hours each day. This subtle reduction follows the peak daylight of 14 hours in June and July, setting the stage for the cozy ambiance of autumn. While August still enjoys 13 hours of light, September signals the start of shorter days, with daylight hours gradually tapering off as the year progresses. The rhythmic ebb and flow of daylight serves as a reminder of nature's cycles, leading us into the crisp days of October and beyond, when 10 hours becomes the norm in November.

Average Daylight Hours in Long Beach for September

The chart illustrates the variation in daylight duration in Long 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 9m10h 57m11h 59m13h 3m13h 56m14h 22m14h 8m13h 20m12h 20m11h 17m10h 22m9h 54m
Data source: Long Beach daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Long Beach

In September, Long Beach experiences a gentle revitalization in its breezes, with an average wind speed of 4.1 m/s (9 mph). This marks a slight increase from the quieter, languid days of August, when winds dipped to 3.7 m/s (8 mph). After a summer characterized by decreasing wind activity, September's breezes provide a refreshing shift, anticipating the more robust gusts of autumn, evident as speeds begin to rise again moving into October at 4.7 m/s (10 mph). Overall, September stands as a transitional month, hinting at the invigorating winds to come while still cherishing the mellow atmosphere of summer's end.

Average September Wind Speed in Long Beach

The chart displays monthly wind speed patterns in Long 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.
JanFebMarAprMayJunJulAugSepOctNovDec5.05.45.45.05.14.94.63.74.1 m/s4.75.24.9
Data source: Long Beach September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Long Beach Compares to Other Months

The weather in Long 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 Long Beach and find detailed weather information for every month.

September and January present strikingly different weather patterns. In September, temperatures range from a minimum of 14°C (58°F) to a sizzling maximum of 32°C (89°F), with an average of 25°C (78°F). The month also experiences significant rainfall, totaling 212 mm (8.4 in) over 12 days, contributing to a high humidity level of 81%. In contrast, January's weather is much cooler, with temperatures dipping as low as -6°C (21°F) and averaging only 10°C (50°F). The maximum temperature reaches 21°C (71°F), and precipitation is notably less at 70 mm (2.8 in) across 9 days, while humidity hovers around 83%. This seasonal shift not only affects temperatures and precipitation but also influences the overall feel of the region’s climate. For more details on January weather, you can explore Long Beach weather in January.

September and February present striking contrasts in weather. In September, temperatures range from a minimum of 14°C (58°F) to a warm average of 25°C (78°F), peaking at 32°C (89°F). This month also experiences significant rainfall, with 212 mm (8.4 in) across about 12 days, and humidity levels soaring to 81%. In contrast, February boasts much cooler conditions, with a minimum of -1°C (30°F), an average temperature of 12°C (54°F), and a maximum of 21°C (71°F). Precipitation is lighter in February, totaling 108 mm (4.3 in) over approximately 10 days, and humidity remains slightly lower at 79%. For a deeper dive into February weather specifics, check out Long Beach weather in February.

September and March present a striking contrast in weather conditions. September boasts warmer temperatures, with a minimum of 14°C (58°F) and an average of 25°C (78°F), peaking at 32°C (89°F). The month is also characterized by significant rainfall, accumulating 212 mm (8.4 in) over about 12 days, coupled with high humidity levels of 81%. In contrast, March experiences cooler temperatures, starting at a minimum of -1°C (31°F) and averaging 14°C (57°F), with a maximum of 23°C (74°F). Precipitation in March is much lower, totaling 75 mm (2.9 in) over about 9 days, and the humidity is slightly lower at 79%. For more detailed insights into March's weather, check out Long Beach weather in March.

When comparing the weather between September and April, notable differences emerge. September boasts warmer temperatures, with minimums of 14°C (58°F) and maximums reaching up to 32°C (89°F), while April sees cooler conditions, where temperatures range from a low of 4°C (40°F) to a high of 26°C (79°F). Additionally, September experiences significantly higher precipitation, totaling 212 mm (8.4 in) over 12 days, compared to April's 95 mm (3.7 in) over just 8 days. Humidity levels are relatively similar, with September at 81% and April at 78%. For more detailed insights, you can check Long Beach weather in April.

September and May present distinct weather patterns, with September being generally warmer and wetter. In September, temperatures range from a minimum of 14°C (58°F) to a maximum of 32°C (89°F), while May sees a slightly cooler temperature range from 11°C (52°F) to the same maximum of 32°C (89°F). Precipitation is notably higher in September, totaling 212 mm (8.4 in) over 12 days, compared to May's 107 mm (4.2 in) over 8 days. Additionally, September's humidity level is slightly elevated at 81%, while May has a slightly lower 78% humidity. For a closer look at May weather specifics, you can check Long Beach weather in May.

When comparing the weather of September and June, we notice some intriguing similarities and differences. Both months have an average temperature of 25°C (78°F), making them quite pleasant. However, September tends to be a bit warmer overall, with maximum temperatures reaching up to 32°C (89°F) compared to June's 31°C (88°F). In terms of precipitation, September sees more rain, accumulating 212 mm (8.4 in) over 12 days, while June experiences less rain at 138 mm (5.4 in), albeit over a greater number of days (16). Additionally, humidity levels are slightly higher in September at 81%, compared to June's 78%. For a closer look at the weather specifics during June, you can check out Long Beach weather in June.

In comparing the weather of September and July, it is clear that September experiences a wider range of temperatures, with minimums around 14°C (58°F) and maximums reaching up to 32°C (89°F), leading to an average temperature of 25°C (78°F). In contrast, July tends to be warmer overall, with minimum temperatures starting at 20°C (69°F) and average temperatures around 27°C (81°F), peaking at a maximum of 31°C (88°F). September also sees more rainfall, accumulating 212 mm (8.4 in) over approximately 12 days, while July has slightly less precipitation at 163 mm (6.4 in) spread across 16 days, contributing to a similarly high humidity level of 81% in September compared to 82% in July. For more details on July weather, you can visit Long Beach weather in July.

In comparing the weather between September and August, September exhibits slightly cooler temperatures, with a minimum of 14°C (58°F) and an average of 25°C (78°F), whereas August starts warmer with a minimum of 20°C (69°F) and an average of 27°C (80°F). Both months share the same maximum temperature of 32°C (89°F). Precipitation levels are relatively similar, with September receiving 212 mm (8.4 in) over 12 days, slightly more than August's 204 mm (8.0 in) over 21 days. Humidity remains constant at 81% for both months. For a deeper look at August weather specifics, visit Long Beach weather in August.

September and October showcase a noticeable shift in weather patterns. In September, temperatures range from a minimum of 14°C (58°F) to a maximum of 32°C (89°F), with an average of 25°C (78°F). This month is characterized by high precipitation, totaling 212 mm (8.4 in) over 12 days, and humidity levels reaching 81%. In contrast, October experiences cooler temperatures, with a minimum of 7°C (45°F) and a maximum of 30°C (86°F), averaging 22°C (71°F). Precipitation decreases significantly to 67 mm (2.6 in) spread over only 8 days, while humidity slightly drops to 78%. For more detailed insights, you can check Long Beach weather in October.

September and November present significantly different weather patterns. In September, temperatures range from a mild 14°C (58°F) to a hot 32°C (89°F), with an average of 25°C (78°F). The month is characterized by high humidity at 81% and notable precipitation, totaling 212 mm (8.4 in) over 12 days. In contrast, November's temperatures drop considerably, with a minimum of 2°C (36°F) and a maximum of 26°C (79°F), averaging just 15°C (59°F). Precipitation also lessens to 104 mm (4.1 in) over 9 days, while humidity remains relatively high at 82%. For those looking to understand what to expect during November, Long Beach weather in November offers detailed insights.

September's weather is characterized by warm temperatures, with an average of 25°C (78°F) and maximums reaching up to 32°C (89°F). The month experiences notable rainfall, totaling 212 mm (8.4 in) over about 12 days, and humidity levels remain high at 81%. In stark contrast, December sees much cooler temperatures, with an average of 12°C (54°F) and maximums of 23°C (73°F). Precipitation decreases to 132 mm (5.2 in) over approximately 10 days, and humidity rises slightly to 84%, creating a crisp winter atmosphere. For more detailed insights, you can check the Long Beach weather in December.

Compare Long Beach's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Long Beach

As September unfolds in Long Beach, the weather offers a unique blend of warmth and moisture that sets it apart from other months. With temperatures typically reaching their peak, the days are pleasantly warm, but the increased humidity and notable precipitation, which strikes approximately half the month, create a distinct coastal ambiance. This transitional time marks the shift from summer's heat, inviting those who relish the gentle ocean breeze and the vibrant fallout of late seasonal blooms. For a deeper dive into the engaging climate nuances of Long Beach, explore Long Beach Climate.