September Weather in San Carlos, Mexico

Last updated: April 22, 2025

September in San Carlos, Mexico showcases a dynamic climate, characterized by warm temperatures and notable humidity. With maximum daytime highs reaching 37°C (99°F), the average temperature sits comfortably at 25°C (78°F), while cooler nights dip to a minimum of 16°C (61°F). This month is also marked by significant rainfall, accumulating to 223 mm (8.8 in) over approximately 18 days, contributing to the region's lush landscapes. With humidity levels around 75%, the warm and moist conditions create a unique atmosphere, ideal for enjoying the stunning natural beauty of this coastal paradise.

September Temperature in San Carlos

In September, San Carlos, Mexico, enjoys a delightful transition as temperatures begin to cool slightly from the summer heat. With minimums around 16°C (61°F) and an average of 25°C (78°F), the weather remains pleasantly warm, perfect for outdoor activities. Although daytime highs still reach up to 37°C (99°F), the overall trend shows a gradual easing of the heat compared to the peak summer months. This shift creates an inviting atmosphere for both locals and visitors who want to relish the sun without the intense heat that characterizes the earlier summer months. September's climate sets the stage for a beautiful autumn, blending warmth with the promise of cooler days ahead.

September Weather in San Carlos: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in San Carlos, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec606470757981818277726562
Data source: Temperature data for San Carlos 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 San Carlos

September marks a significant peak in precipitation for San Carlos, Mexico, as the region experiences an average of 223 mm (8.8 in) of rain over approximately 18 days. This dramatic increase follows a pattern of rising moisture during the summer months, with June and July also recording high totals of 182 mm and 166 mm respectively. However, September's rainfall stands out not only for its volume but for its potential to rejuvenate the lush landscapes after the drier spring months. As the weather begins to cool into October, the precipitation sharply declines to 101 mm (4.0 in), ushering in a much drier season. This trend underscores a defining characteristic of San Carlos's climate—an intense monsoon season that creates a vibrant backdrop leading into fall.

September Precipitation Trends in San Carlos

The chart displays monthly precipitation patterns in San Carlos, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1615444985182166902241014213
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in San Carlos

In September, the humidity in San Carlos, Mexico, settles at 75%, marking a slight increase from the drier months of July and August, which recorded 68% and 67% respectively. This late-summer uptick reflects a gradual shift as the region transitions towards the wetter season. Throughout the year, humidity remains notably high, peaking in the winter months of January and December at 84% and 86%, creating a contrast to the more comfortable levels experienced in the peak of summer. Overall, September serves as a pivotal point in San Carlos's humidity journey, bridging the dry summer and the more humid fall months ahead.

September Average Humidity in San Carlos

This chart illustrates the average monthly humidity levels in San Carlos, 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%83%78%81%82%74%68%67%75%78%83%86%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in San Carlos

In September, San Carlos, Mexico, continues to experience extreme ultraviolet (UV) radiation, with a UV Index maintaining at 12. This marks a consistent trend seen from April to August, where caution is essential as even brief exposure can lead to sunburn in just 10 minutes. The intensity in September signals that outdoor enthusiasts should prioritize sun protection to mitigate the risks associated with prolonged sun exposure. As we transition into the fall months, the UV Index will begin to decline, but for now, the bright sun emphasizes the importance of staying safe while enjoying the stunning coastal scenery. For more detailed information, visit San Carlos UV Index.

Maximum UV Index Levels in San Carlos for September

The chart shows the monthly maximum UV Index (UVI) for San Carlos 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.
JanFebMarAprMayJunJulAugSepOctNovDec79111212121212121086
Data source: San Carlos 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 San Carlos

In September, San Carlos, Mexico enjoys a delightful retreat from the summer heat with 293 hours of sunshine. While this marks a slight dip from the sun-drenched days of August, which boasted a remarkable 340 hours, it still reflects a strong summer lingering into the early fall. Following the peak sunshine months of July and August, September offers a perfect blend of warmth and clearer skies, making it an ideal time for outdoor adventures. As the year transitions into October, the sunshine begins to wane, but with 288 hours still on the horizon, the charm of San Carlos remains irresistible. The overall trend showcases a vibrant sunny season, peaking in the height of summer, but consistently providing ample sunshine for those seeking a warm getaway well into the autumn months.

Monthly Sunshine Duration in San Carlos: September Highlighted

The September sunshine duration represents the total number of hours San Carlos 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.
JanFebMarAprMayJunJulAugSepOctNovDec206h249h290h294h328h331h335h340h293h288h263h269h
Data source: San Carlos September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Carlos During September

September in San Carlos, Mexico, brings a lower chance of sunny weather, with only a 40% likelihood of sunshine gracing the skies. This marks a notable decline compared to the vibrant summer months of July and August, where sunshine chances peaked at 36% and 62% respectively. Transitioning from the summer heat, September trends towards increased cloud cover and the potential for rain, as the rainy season continues. However, as the month progresses, residents and travelers alike can anticipate a gradual return to brighter skies, leading into the sunnier days of October with a 56% chance of sun. Overall, while September may not boast the sunniest weather, it still holds its unique charm in San Carlos.

Percentage of Sunny Days in September in San Carlos

The chart illustrates the percentage of sunny days in San Carlos 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 San Carlos experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec49%60%59%51%50%43%36%62%40%56%58%63%
Data source: San Carlos September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Carlos in September

September in San Carlos, Mexico, marks a gentle transition as daylight begins to wane, offering 12 hours of sunlight. Following the vibrant peak of 13 hours in the summer months, the daylight duration starts to dip, echoing the gradual shift from the heat of summer to the cooler embrace of autumn. This month’s sunshine still allows plenty of time for outdoor adventures and sunset views, while hinting at the shorter days ahead. As daylight diminishes further into the fall, a rhythm emerges: longer nights and shorter days dominate the landscape, creating a cozy atmosphere perfect for enjoying the serene beauty of San Carlos.

Average Daylight Hours in San Carlos for September

The chart illustrates the variation in daylight duration in San Carlos throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 47m11h 19m12h 1m12h 44m13h 20m13h 37m13h 27m12h 56m12h 15m11h 32m10h 55m10h 37m
Data source: San Carlos daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in San Carlos

In September, the winds in San Carlos, Mexico begin to mellow, with an average speed of just 2.6 m/s (6 mph), marking it as one of the calmer months of the year. This gentle breeze contrasts with the early spring months, where wind speeds peak closer to 3.8 m/s (9 mph) in March and May. The trend shows a gradual decline from the summer, where speeds hover around a consistent 3.0 to 3.3 m/s (7 mph), reflecting the transition towards cooler autumn temperatures. As the year progresses into October, wind speeds slightly increase, but September notably stands out as a serene month for those seeking a peaceful coastal experience.

Average September Wind Speed in San Carlos

The chart displays monthly wind speed patterns in San Carlos, 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.
JanFebMarAprMayJunJulAugSepOctNovDec3.23.63.83.73.83.13.03.32.6 m/s2.73.03.3
Data source: San Carlos September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in San Carlos Compares to Other Months

The weather in San Carlos 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 Carlos and find detailed weather information for every month.

September and January showcase contrasting weather patterns. In September, temperatures range from a minimum of 16°C (61°F) to a scorching maximum of 37°C (99°F), with an average of 25°C (78°F). This month also sees significant rainfall, with approximately 223 mm (8.8 in) spread over 18 days, resulting in a humidity level of 75%. In stark contrast, January experiences much colder conditions, with temperatures falling as low as -2°C (28°F) and peaking at 34°C (93°F), averaging around 16°C (60°F). Rainfall is minimal in January, totaling only 16 mm (0.6 in) across just 4 days, and humidity rises to 84%. For a detailed look at January conditions, check San Carlos weather in January.

September and February exhibit distinctly different weather patterns. In September, temperatures range from a minimum of 16°C (61°F) to a scorching maximum of 37°C (99°F), with an average of 25°C (78°F). This month is characterized by high humidity at 75% and significant precipitation of 223 mm (8.8 in), occurring over 18 days. In contrast, February experiences cooler temperatures, with a minimum of -5°C (24°F) and an average of 18°C (64°F), peaking at 35°C (96°F). February also sees dramatically reduced rainfall, with only 14 mm (0.6 in) falling over 3 days and slightly higher humidity at 83%. The climate transition between these months highlights the shift from a wet, humid late summer to a cooler, drier winter. For more detailed insights into February weather, you can visit San Carlos weather in February.

September and March exhibit notable differences in weather patterns. In September, the average temperature is warmer at 25°C (78°F) with maximums reaching 37°C (99°F), and the humidity is relatively high at 75%. This month also sees considerable rainfall, averaging 223 mm (8.8 in) across 18 days. Conversely, March experiences cooler temperatures, with a minimum of 3°C (38°F) and an average of 21°C (70°F), but still showcases similar maximums of 37°C (100°F). Precipitation in March is significantly lower at 44 mm (1.7 in) over just 6 days, while humidity remains slightly elevated at 78%. For a more detailed outlook, check out San Carlos weather in March.

In comparing the weather of September and April, September tends to be warmer, with average temperatures reaching 25°C (78°F) and highs soaring to 37°C (99°F). The month also experiences significantly more precipitation, totaling 223 mm (8.8 in) over 18 days, contributing to a humidity level of 75%. In contrast, April offers cooler conditions with an average temperature of 24°C (75°F) and maximum temperatures of 40°C (103°F). Precipitation in April is much lower at 49 mm (1.9 in) over just 7 days, though humidity is slightly higher at 81%. For a closer look at April's weather patterns, you can visit San Carlos weather in April.

When comparing the weather in September and May, several distinct differences emerge. September typically experiences a wider temperature range, with lows around 16°C (61°F) and highs reaching up to 37°C (99°F). The average temperature in September is 25°C (78°F) accompanied by a notable amount of rainfall, with 223 mm (8.8 in) spread over 18 days and humidity at 75%. In contrast, May boasts slightly cooler minimum temperatures of 13°C (57°F) and maximums soaring to 41°C (107°F), averaging 26°C (80°F). However, May is considerably drier, with only 85 mm (3.3 in) of precipitation over 12 days and slightly higher humidity at 82%. For detailed insights into the weather specifics during May, you can visit San Carlos weather in May.

In comparing the weather between September and June, both months exhibit high temperatures, though September tends to be slightly cooler with an average of 25°C (78°F) compared to June's average of 27°C (81°F). June experiences higher maximum temperatures, reaching up to 39°C (103°F), while September peaks at 37°C (99°F). Precipitation is more pronounced in September, with 223 mm (8.8 in) occurring over 18 days, compared to June's 182 mm (7.2 in) over 16 days. Humidity levels are quite similar, with September at 75% and June at 74%. For a detailed look at June weather, you can check San Carlos weather in June.

When comparing the weather in September to that of July, several notable differences emerge. September tends to have a slightly wider temperature range, with minimums around 16°C (61°F) and maximums reaching up to 37°C (99°F), while July experiences minimums of 20°C (68°F) and can peak at 38°C (101°F). Additionally, September is characterized by higher precipitation levels, averaging 223 mm (8.8 in) over approximately 18 days, compared to July's 166 mm (6.5 in) over 14 days. September also has greater humidity, averaging 75%, in contrast to July's 68%. For a more detailed look at July weather, you can check out San Carlos weather in July.

In comparing the weather between August and September, we find that September experiences slightly cooler temperatures, with minimums of 16°C (61°F) compared to August's 20°C (69°F). The average temperature in September is 25°C (78°F), while August sees a warmer average of 28°C (82°F). Notably, September has a higher maximum temperature of 37°C (99°F) versus August's peak of 38°C (100°F). In terms of precipitation, September is significantly wetter, receiving 223 mm (8.8 in) over 18 days, while August has only 90 mm (3.6 in) over 15 days. September also maintains a higher humidity level at 75% compared to August’s 67%. For a detailed look at August's weather, you can visit San Carlos weather in August.

September's weather showcases high temperatures, with averages reaching 25°C (78°F) and peaks up to 37°C (99°F). The month experiences significant rainfall, totaling 223 mm (8.8 in) over 18 days, accompanied by a humidity level of 75%. In contrast, October brings a more temperate climate, with average temperatures cooling to 22°C (72°F) and maximums of 34°C (94°F). Rainfall is noticeably reduced to 101 mm (4.0 in) over 12 days, and humidity slightly increases to 78%. For more details, you can check San Carlos weather in October.

September and November exhibit striking differences in weather patterns. In September, temperatures range significantly from a minimum of 16°C (61°F) to a scorching maximum of 37°C (99°F), with an average of 25°C (78°F). This month also sees high levels of precipitation, totaling 223 mm (8.8 in) over 18 days, resulting in a humidity level of 75%. In contrast, November experiences much cooler temperatures, with a minimum of 2°C (37°F), an average of 19°C (66°F), and a maximum of 31°C (88°F). Rainfall drops sharply to 42 mm (1.7 in) over just 5 days, alongside a higher humidity level of 83%. For more details on November weather, check out San Carlos weather in November.

September and December present strikingly different weather conditions. In September, temperatures average around 25°C (78°F), peaking at a sweltering 37°C (99°F), accompanied by high humidity at 75% and significant rainfall of 223 mm (8.8 in) over 18 days. In contrast, December brings a much cooler climate with average temperatures of 17°C (62°F), ranging from a chilly minimum of 0°C (32°F) to a comfortable maximum of 32°C (89°F). Rainfall is minimal in December, with only 13 mm (0.5 in) over 3 days, and humidity increases to 86%, making the air feel crisp. For more detailed information, check out San Carlos weather in December.

Compare San Carlos's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in San Carlos

As September unfolds in San Carlos, the weather paints a vibrant picture distinctly different from other months. With temperatures peaking at a sweltering 37°C, the heat can be intense, but the average dips to a more comfortable 25°C, providing a respite during the day. While the month is characterized by higher humidity at 75% and noteworthy precipitation, with 223 mm falling over 18 days, it adds a refreshing dynamic to the otherwise scorching atmosphere. This blend of heat and moisture makes September a unique time to experience the lush transformations in the landscape. For a deeper look into how September's conditions fit within the broader climate patterns, check out San Carlos Climate.