September Weather in Del Mar, United States

Last updated: February 24, 2025

In September, Del Mar, United States basks in delightful weather, showcasing a maximum temperature of 32°C (90°F) and a pleasant average of 21°C (71°F). With a minimum dipping to around 15°C (60°F), the climate invites outdoor activities and beach strolls. Remarkably, the month experiences just 5 mm (0.2 in) of precipitation over zero rainy days, ensuring sunshine reigns supreme. Complemented by a comfortable humidity level of 52%, September is perfect for enjoying the scenic beauty and vibrant atmosphere of this coastal gem.

September Temperature in Del Mar

In September, Del Mar basks in pleasantly warm temperatures as summer edges into fall. With a minimum of around 15°C (60°F) and an average of 21°C (71°F), the month offers a comfortable climate for beachgoers and outdoor enthusiasts alike. The maximum can reach up to 32°C (90°F), providing ample opportunity for sunbathing and enjoying the picturesque coast. This trend marks a gradual transition from the higher heat of July and August, yet still retains a warmth that invites both relaxation and adventure, making September a lovely time to visit this coastal gem.

September Weather in Del Mar: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Del Mar, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec565658616265707271686257
Data source: Temperature data for Del Mar 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 Del Mar

In September, Del Mar experiences a notable shift in precipitation patterns, with only 5 mm (0.2 in) recorded, marking a significant dip following the summer months where rain was virtually absent. This month continues the trend of dry conditions, as September sees no precipitation days, mirroring the aridness of June, July, and August. The general downward trend in rainfall from May onward culminates in this minimal precipitation, highlighting the region's dry climate during late summer. As autumn approaches, residents and visitors alike can anticipate a gradual increase in moisture levels in the months to come, particularly in October and November, where precipitation levels rise once more.

September Precipitation Trends in Del Mar

The chart displays monthly precipitation patterns in Del Mar, 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.
JanFebMarAprMayJunJulAugSepOctNovDec67726431234225133473
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Del Mar

In September, Del Mar experiences a notable shift in humidity, with levels settling at 52%. This marks a rise from the drier summer months, where humidity dipped to a low of 42% in August. As the seasons transition, the air becomes more comfortable and slightly more humid compared to the peak summer heat, yet it remains significantly lower than the winter months. The trend reveals a gradual increase in moisture as the year progresses, with January starting off at 72%, building back to this moderate September level before climbing to 58% in October. This pattern highlights the coastal region's characteristic fluctuations, offering a refreshing breath of air as Del Mar shifts into the fall season.

September Average Humidity in Del Mar

This chart illustrates the average monthly humidity levels in Del Mar, 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.
JanFebMarAprMayJunJulAugSepOctNovDec72%77%67%56%46%48%46%42%52%58%66%74%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Del Mar

In September, Del Mar, California maintains a UV Index of 10, categorizing it as very high exposure, with a burn time of just 15 minutes. This trend follows the summer months, where the UV Index peaked at an extreme level of 11 in July and August. As temperatures begin to cool in autumn, the UV Index drops to a more moderate level in October with an index of 7. However, September’s UV Index indicates that sun protection remains essential, as the risk of skin damage during short sun exposure is significant. For a detailed outlook on UV intensity throughout the year, check out Del Mar UV Index.

Maximum UV Index Levels in Del Mar for September

The chart shows the monthly maximum UV Index (UVI) for Del Mar 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.
JanFebMarAprMayJunJulAugSepOctNovDec469101112111010754
Data source: Del Mar 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 Del Mar

As the summer haze begins to wane, September in Del Mar still basks in a generous 319 hours of sunshine, making it one of the sunlit jewels of late summer. This month showcases a slight decline from the peak sunlight of July and August, which boasted 378 and 361 hours respectively. Yet, September’s warm rays invite both locals and visitors to savor the lingering outdoor vibes before the cooler months arrive. As the sunlight gradually decreases into autumn, with October at 296 hours, September serves as a beautiful bridge, reminding us that there's still plenty of time to enjoy the enchanting coastal charm of Del Mar under its golden skies.

Monthly Sunshine Duration in Del Mar: September Highlighted

The September sunshine duration represents the total number of hours Del Mar 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.
JanFebMarAprMayJunJulAugSepOctNovDec191h243h298h324h364h369h378h361h319h296h256h228h
Data source: Del Mar September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Del Mar During September

September in Del Mar, United States, enjoys a notable increase in sunny weather, boasting a 67% chance of sunshine, making it one of the brightest months of the year. This trend follows a summer peak, as August also features a high 66% chance of sun. As the summer warmth lingers, September provides an ideal transition into the fall season, juxtaposing the sunny days ahead with the cooler temperatures that October brings, which sees a slight dip to 64%. The overall pattern reveals a community embraced by sun throughout the year, with September standing out as a promising month for outdoor activities and beach lovers.

Percentage of Sunny Days in September in Del Mar

The chart illustrates the percentage of sunny days in Del Mar 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 Del Mar experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec62%60%62%51%45%55%60%66%67%64%66%47%
Data source: Del Mar September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Del Mar in September

As summer fades into autumn in Del Mar, September sees a gentle decline in daylight hours, with the sun shining for about 12 hours each day. This is a slight reduction from the peak of 14 hours in June and July, signaling the gradual transition towards the shorter days of fall. The trend showcases a steady decrease in daylight from the summer solstice and hints at the cozy, reflective evenings to come. As the month progresses, residents can bask in the golden glow of the early autumn sun while savoring those longer twilight moments.

Average Daylight Hours in Del Mar for September

The chart illustrates the variation in daylight duration in Del Mar throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 14m11h12h13h 1m13h 52m14h 17m14h 3m13h 17m12h 19m11h 18m10h 26m9h 59m
Data source: Del Mar daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Del Mar

As summer gives way to autumn in Del Mar, September greets residents and visitors with a gentle breeze, featuring an average wind speed of 2.6 m/s (6 mph). This marks a slight dip from the summer months, where June and July maintained consistent winds around 2.9 m/s. Interestingly, September's winds transition smoothly from the steady summer patterns, mirroring the gradual coolness that begins to permeate the air. Following this month, October sees a further reduction to 2.5 m/s, hinting at the approaching winter and a return to the calmer, quieter breezes typical of the fall season. Overall, September is a lovely balance of lingering summer warmth and the subtle shifts toward autumn, all carried by its soft winds.

Average September Wind Speed in Del Mar

The chart displays monthly wind speed patterns in Del Mar, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.52.32.92.92.92.92.72.72.6 m/s2.52.02.7
Data source: Del Mar September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Del Mar Compares to Other Months

The weather in Del Mar 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 Del Mar and find detailed weather information for every month.

In September, the weather is generally warm and pleasant, with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 32°C (90°F) and an average of 21°C (71°F). The month is relatively dry, receiving only 5 mm (0.2 in) of precipitation over no rainy days, and the humidity hovers around 52%. In contrast, January experiences cooler temperatures with a minimum of 6°C (43°F) and a maximum of 26°C (79°F), averaging 14°C (57°F). This month is significantly wetter, with 67 mm (2.6 in) of precipitation spread across about 5 rainy days, and the humidity increases to 72%. For more details on January weather, you can visit Del Mar weather in January.

September and February present striking contrasts in weather patterns. In September, temperatures range from a mild minimum of 15°C (60°F) to a warm maximum of 32°C (90°F), with an average of 21°C (71°F). This month is characterized by low precipitation, averaging just 5 mm, and a humidity level of 52%, making for pleasant, sunny days. Conversely, February experiences cooler temperatures, with a minimum of 5°C (42°F) and a maximum of 26°C (79°F), averaging only 13°C (56°F). This month sees increased rainfall, accumulating 72 mm over approximately 7 days, and higher humidity at 77%. For a closer look at February weather specifics, you can refer to Del Mar weather in February.

When comparing September and March weather, it’s clear that September boasts warmer temperatures, with daytime highs averaging around 21°C (71°F) and peaking at 32°C (90°F). In contrast, March is considerably cooler, with average temperatures of only 14°C (58°F) and maximums reaching 25°C (77°F). Additionally, September experiences minimal precipitation, averaging just 5 mm over no rain days, whereas March is much wetter, accumulating 64 mm of rain over 10 days. The humidity levels also differ, with March being more humid at 67% compared to September's 52%. For a closer look at March weather specifics, check out Del Mar weather in March.

September typically showcases warmer temperatures compared to April, with averages around 21°C (71°F) and highs reaching up to 32°C (90°F). In contrast, April experiences cooler conditions, with an average temperature of 16°C (61°F) and a maximum of 29°C (84°F). Additionally, September tends to be much drier, with only 5 mm (0.2 in) of precipitation and no rainy days, whereas April sees more rain with 30 mm (1.2 in) of precipitation spread over three days. Humidity levels are fairly similar, with September at 52% and April slightly higher at 56%. For more detailed information, visit Del Mar weather in April.

In September, the weather tends to be warmer, with average temperatures reaching 21°C (71°F) and maximums soaring up to 32°C (90°F). The month is notably dry, receiving only 5 mm (0.2 in) of precipitation, which contributes to a relatively comfortable humidity level of 52%. In contrast, May offers cooler temperatures, with averages around 17°C (62°F) and highs peaking at 26°C (79°F). This month experiences more precipitation, totaling 23 mm (0.9 in) across four days, and has slightly lower humidity at 46%. For more specific details on May weather, you can check Del Mar weather in May.

In comparing the weather of September and June, September tends to be warmer with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 32°C (90°F), averaging around 21°C (71°F). In contrast, June has slightly cooler temperatures, starting at a minimum of 14°C (57°F) and peaking at 29°C (85°F), with an average of 18°C (65°F). Both months experience minimal precipitation, with September receiving 5 mm (0.2 in) and June slightly less at 4 mm (0.2 in), and neither month sees any rainy days. Humidity levels are also comparable, with September at 52% and June at 48%, making both months relatively comfortable. For a more detailed look at the weather in June, you can visit Del Mar weather in June.

When comparing the weather in September and July, we see that both months offer warm temperatures, with average highs reaching 32°C (89°F in July and 90°F in September). July has a slightly cooler minimum temperature of 16°C (61°F) compared to September's 15°C (60°F), but both months share a similar average temperature of 21°C (70°F in July and 71°F in September). Precipitation is minimal in both months, with July receiving only 2 mm and September 5 mm, both resulting in zero rainy days. Additionally, September has a higher humidity level at 52%, compared to July's 46%. For more details, you can check Del Mar weather in July.

In comparing the weather of September to that of August, we can see some notable differences. September tends to have slightly cooler temperatures than August, with a minimum of 15°C (60°F) and an average of 21°C (71°F), compared to August's minimum of 17°C (63°F) and average of 22°C (72°F). The maximum temperature in September reaches 32°C (90°F), which is a bit higher than August's max of 30°C (86°F). Additionally, September experiences slightly less precipitation, with only 5 mm (0.2 in) compared to 2 mm (0.1 in) in August, and both months have no rainy days. Notably, September has a higher humidity of 52% compared to August's 42%. For more detailed insights on August weather, visit Del Mar weather in August.

September typically offers warmer temperatures, with averages around 21°C (71°F) and highs reaching up to 32°C (90°F). This month is characterized by minimal precipitation, averaging only 5 mm (0.2 in) and featuring no rainy days, making it a drier period with a humidity level of 52%. In contrast, October introduces cooler conditions, with a lower average temperature of 20°C (68°F) and maximums of 34°C (93°F). Rain becomes more frequent, with 13 mm (0.5 in) of precipitation over about two days, and humidity rises slightly to 58%. For more detailed insights, check out Del Mar weather in October.

In September, the weather is warm and pleasant, with temperatures ranging from a minimum of 15°C (60°F) to a maximum of 32°C (90°F), and very little precipitation, only 5 mm (0.2 in) over no rainy days. The humidity sits at a comfortable 52%. In contrast, November brings cooler temperatures, with lows dropping to 9°C (48°F) and a maximum of 28°C (83°F). This month also sees increased rainfall, with 34 mm (1.3 in) occurring over two days, contributing to a higher humidity level at 66%. For more details on a specific location, check Del Mar weather in November.

September generally experiences warmer temperatures, with minimums around 15°C (60°F) and maximums reaching up to 32°C (90°F), creating a comfortable and inviting atmosphere. Precipitation is minimal in September, averaging only 5 mm (0.2 in) over the course of the month. In contrast, December brings cooler weather, with temperatures ranging from a minimum of 6°C (43°F) to a maximum of 25°C (77°F), and the likelihood of rain increases significantly, totaling around 73 mm (2.9 in) over 6 days. Additionally, December is notably more humid, with levels around 74%, compared to September's 52%. For more detailed information, you can check Del Mar weather in December.

Compare Del Mar's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Del Mar

September in Del Mar stands out as a delightful transition from the warm summer months, offering generally pleasant weather that invites both locals and visitors to bask in the sun. With average temperatures hovering around 21°C (71°F) and maximums reaching up to 32°C (90°F), it's an ideal time to enjoy outdoor activities without the intense heat that characterizes July and August. Interestingly, the month boasts an impressive record of no precipitation, offering clear skies and low humidity at 52%, making it perfect for beach outings and coastal adventures. As the days grow shorter, September provides a unique blend of warmth and comfort, setting the stage for the more temperate autumn ahead. For a deeper dive into the climate trends, visit Del Mar Climate.