Last updated: April 22, 2025
September in San Diego, Mexico, brings warm temperatures, showcasing a maximum of 36°C (97°F) and an average of 28°C (83°F), while nights cool down to a minimum of 23°C (74°F). This month is characterized by its high humidity levels at 88%, contributing to a tropical feel. However, be prepared for ample rainfall, with 143 mm (5.6 in) of precipitation spread over 20 days, making September a month of both warmth and moisture in this coastal paradise.
As September rolls in, San Diego, Mexico, enjoys a pleasant transition from the summer heat, with temperatures reflecting the lingering warmth of the season. With a minimum of 23°C (74°F) and an average reaching 28°C (83°F), the days remain comfortably warm, while the maximum peaks at 36°C (97°F), offering plenty of opportunities for outdoor adventures. This month marks a slight dip from the sweltering highs of August, yet still delivers a delightful atmosphere where the sun shines bright and the evenings cool down just enough to be enjoyable. As summer fades, September's temperatures perfectly balance warmth and comfort, inviting visitors to experience the vibrant culture and breathtaking scenery of this coastal gem.
In September, San Diego, Mexico, experiences a notable peak in rainfall, with 143 mm (5.6 inches) of precipitation spread over 20 days. This month's rainfall continues the trend established in the preceding months, particularly following the summer highs seen in July and August. While July's 86 mm (3.4 in) and August's 152 mm (6.0 in) set the stage for wet conditions, September's slightly lower totals still reflect the region's transition toward the drier months ahead. As the rainy season begins to wind down, the consistent precipitation through September not only sustains the local landscape but also marks a critical time for agriculture and water supply, highlighting the dynamic climate patterns that characterize this vibrant coastal area.
As the summer fades into fall, September in San Diego, Mexico, experiences a peak in humidity, reaching a striking 88%. This rise follows the trend seen in the warmer months, particularly August, when humidity soared to 87%. Interestingly, the levels of humidity have been gradually increasing since April, which recorded a low of 49%. This upward trend highlights the region's transition from the dry spring to the sultry late summer and early fall. With October still maintaining high humidity at 83%, it’s evident that this coastal destination is characterized by its moist and tropical air, especially as it moves into the final months of the year.
In September, San Diego continues to enjoy the summer sun with a UV Index of 12, categorizing it as extreme and suggesting a quick burn time of just 10 minutes. This month maintains the high levels established in the preceding summer months of July and August, where protective measures remain crucial for outdoor activities. As the year transitions into fall, the UV Index slightly decreases, yet remains significant, mirroring the strong UV radiation observed throughout the summer. Sun safety is paramount, so be sure to stay informed and take necessary precautions. For more detailed information, check out San Diego UV Index.
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As summer gently transitions into autumn, September in San Diego, Mexico, continues to bask in generous sunshine with 278 hours of daylight. This month marks a shift from the peak sunshine of May, when the region enjoyed an impressive 360 hours, gradually descending through the warmer months. Following a consistent decline from August's 296 hours, September offers a delightful blend of warmth and bright days, perfectly suited for beach outings and outdoor adventures. While October teases with a slight increase to 298 hours, September remains a vibrant reminder of summer's lingering embrace, setting the stage for the cooler months ahead. The overall trend reflects a rich tapestry of sunlight, making San Diego a perennial destination for sun-seekers.
In San Diego, Mexico, September marks a transition in the weather, with sunny days becoming less frequent as summer wanes. The chance of sunny weather drops to just 40% this month, aligning with July and August, which are typically the cloudiest times of the year. Interestingly, this decrease follows the high probabilities of sunshine in May (80%) and the consistent warmth of early summer. As autumn approaches, the likelihood of sun picks up again, especially in October with a notable 75% chance. Thus, while September may not offer the brightest days, it's a pivotal month that signals a return to more reliable sunshine in the following weeks.
As September rolls into San Diego, the daylight hours settle into a comfortable rhythm, offering residents around 12 hours of sunlight each day. This marks a gentle transition from the longer summer days of June through August, when sunshine stretches to 13 hours. Following September, the days begin to shorten again as the region prepares for the cooler fall months, reminiscent of the steady decrease seen in October and November. The consistency of daylight throughout the year, especially during these months, creates a lovely backdrop for outdoor activities, ensuring that San Diego's vibrant atmosphere is never dimmed by the fading sunlight.
As the months shift toward the end of the year, September brings a noticeable dip in wind speed for San Diego, Mexico, with an average of just 1.4 m/s (3 mph). This marks a decline from the summer months, where stronger breezes had more frequently graced the shoreline, peaking around June with 2.1 m/s (5 mph). Comparatively, the autumn signals a gentle transition; while the winds ease, October slightly rebounds to 1.6 m/s (3 mph). Overall, the trend suggests a pattern of mild winds during late summer and early fall, providing a serene backdrop to the picturesque coastal landscape.
The weather in San Diego 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 San Diego and find detailed weather information for every month.
In September, the weather is typically warm and humid, with temperatures ranging from a minimum of 23°C (74°F) to a maximum of 36°C (97°F). The month experiences significant rainfall, averaging 143 mm (5.6 in) over about 20 days, and humidity levels are high at 88%. In contrast, January offers a much cooler and drier climate, with temperatures ranging from a minimum of 8°C (47°F) to a maximum of 33°C (91°F). Rainfall is minimal, averaging just 6 mm (0.3 in) over 1 day, and humidity levels drop to 76%. For more details about January's weather, you can check San Diego weather in January.
September weather is characterized by a warm climate, with average temperatures ranging from a minimum of 23°C (74°F) to a maximum of 36°C (97°F). This month experiences significant rainfall, totaling 143 mm (5.6 in) over about 20 days, coupled with high humidity levels of 88%. In contrast, February offers a much cooler atmosphere, with temperatures varying from a minimum of 8°C (47°F) to a maximum of 33°C (92°F) and an average of 20°C (69°F). Precipitation dramatically decreases to just 24 mm (0.9 in) over only 2 days, and humidity levels drop to 69%. For more specific information about February conditions, check out San Diego weather in February.
In September, the weather is notably warmer and more humid, with average temperatures ranging from a minimum of 23°C (74°F) to a maximum of 36°C (97°F) and a high average humidity of 88%. This month also experiences significant rainfall, with precipitation averaging 143 mm (5.6 in) over about 20 days. In contrast, March offers a much cooler and drier climate, where temperatures range from a minimum of 10°C (51°F) to a maximum of 34°C (94°F). The average humidity drops to 57%, and precipitation is minimal, often totaling just 2 mm (0.1 in) across zero rainy days. For more detailed insights, you can check San Diego weather in March.
In comparing the weather of September and April, a clear contrast emerges. September is characterized by warmer temperatures, with minimums around 23°C (74°F) and averages reaching 28°C (83°F), peaking at a scorching 36°C (97°F). Additionally, this month experiences significant rainfall, totaling 143 mm (5.6 in) across 20 days, leading to high humidity levels of about 88%. In stark contrast, April boasts much milder conditions, with minimum temperatures dropping to 12°C (53°F) and an average of 24°C (75°F), while also reaching highs of 36°C (97°F). Notably, April sees no precipitation, resulting in a much lower humidity level of 49%. For more details on this month’s weather, you can refer to San Diego weather in April.
When comparing September and May weather, it's striking how distinct these months are. September typically experiences higher temperatures, with a minimum of 23°C (74°F) and an average of 28°C (83°F), peaking at 36°C (97°F). However, it also brings significant rainfall, averaging 143 mm (5.6 in) over about 20 days, resulting in high humidity levels at 88%. In contrast, May offers a milder climate, with temperatures ranging from a minimum of 15°C (60°F) to an average of 26°C (80°F) and a maximum of 37°C (98°F). Notably, May is dry, receiving no precipitation throughout the month and maintaining a more comfortable humidity of 49%. For more insights on May weather, you can check San Diego weather in May.
When comparing the weather in September and June, we can observe some key differences. September features a minimum temperature of 23°C (74°F) and an average of 28°C (83°F), peaking at 36°C (97°F), accompanied by high humidity levels at 88%. In contrast, June enjoys slightly cooler temperatures, with a minimum of 20°C (68°F) and an average of 29°C (84°F), which can reach a maximum of 38°C (100°F). Notably, June experiences much less precipitation, only 26 mm (1.0 in) over just 3 days, compared to September's 143 mm (5.6 in) spread over 20 days. For more detailed insights into June's climate, you can visit San Diego weather in June.
In comparing the weather of September and July, both months showcase warm temperatures, but September tends to be slightly cooler on average. With July's average temperature reaching 29°C (85°F) and a maximum of 37°C (100°F), it is marginally warmer than September, which averages at 28°C (83°F) with a peak of 36°C (97°F). Additionally, September experiences significantly higher precipitation, recording 143 mm (5.6 in) over 20 days, compared to July's 86 mm (3.4 in) over just 14 days. Humidity is also higher in September at 88%, in contrast to July's 82%. For a closer look at the specifics of July's weather, you can refer to San Diego weather in July.
In comparing the weather of September to that of August, we can observe a slight cooling trend. September features temperatures ranging from a minimum of 23°C (74°F) to a maximum of 36°C (97°F), with an average of 28°C (83°F). In contrast, August is marginally warmer, with a higher average temperature of 29°C (85°F) and a maximum reaching up to 37°C (98°F). Additionally, both months experience significant rainfall, but September sees a slight decrease in total precipitation, amounting to 143 mm (5.6 in) over 20 days compared to August's 152 mm (6.0 in) over 19 days. Humidity levels are relatively consistent, with September at 88% and August at 87%. This data highlights the gradual transition from summer to early fall, showcasing just subtle changes in weather. For further details, you can visit San Diego weather in August.
September and October present a notable shift in weather conditions. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 36°C (97°F), with an average of 28°C (83°F). This month also sees higher precipitation, totaling 143 mm (5.6 in) spread over 20 days, along with elevated humidity levels at 88%. In contrast, October features slightly cooler temperatures, with a minimum of 18°C (64°F) and a maximum of 37°C (98°F), yet maintaining the same average of 28°C (83°F). The month is much drier, recording only 43 mm (1.7 in) of precipitation over just 5 days and a reduced humidity level of 83%. For more details on October weather, you can visit San Diego weather in October.
In September, temperatures are typically warmer, with a minimum of 23°C (74°F) and an average of 28°C (83°F), often reaching a maximum of 36°C (97°F). The month also experiences significant rainfall, averaging 143 mm (5.6 in) over 20 days, resulting in high humidity levels around 88%. In contrast, November offers a cooler climate, with a minimum temperature of 14°C (58°F) and an average of 25°C (77°F), still peaking at 36°C (98°F). Precipitation drops dramatically to 46 mm (1.8 in) over just 2 days, while humidity remains relatively high at 84%. For more detailed information, you can check San Diego weather in November.
In September, the weather is characterized by warm temperatures, with a minimum of 23°C (74°F), averaging 28°C (83°F), and reaching highs of 36°C (97°F). This month also experiences significant rainfall, with a total of 143 mm (5.6 in) over approximately 20 days, contributing to a high humidity level of 88%. In contrast, December brings a much cooler climate, with a minimum temperature of 10°C (51°F), an average of 21°C (70°F), and a maximum of 34°C (93°F). Additionally, December sees considerably less precipitation, only 17 mm (0.7 in) over merely 2 days, and a slightly lower humidity at 86%. For more detailed insights, check out San Diego weather in December.
As September unfolds in San Diego, the transition to autumn brings a noticeable shift in weather patterns. This month is characterized by warmer temperatures, peaking higher than what is typical in the summer, yet they are often accompanied by increased humidity. With an average temperature comfortably resting at 28°C (83°F), the city experiences a dampness that leads to frequent rain, contributing to 20 days of precipitation, a stark contrast to the drier months preceding it. This makes September a unique blend of summer warmth and autumnal moisture, inviting residents and visitors alike to embrace the beauty of coastal rain. For more insights into how September fits within the overall annual weather panorama, explore San Diego Climate.