September Weather in San Blas, Mexico

Last updated: April 22, 2025

In September, San Blas, Mexico, experiences a warm and humid climate characterized by an average temperature of 27°C (81°F), peaking at a maximum of 32°C (91°F) and dipping to a minimum of 23°C (74°F). This coastal town sees significant rainfall, with 367 mm (14.5 in) of precipitation spread across 27 days, making it one of the wettest months of the year. The high humidity level of 78% adds to the tropical feel, creating a lush and vibrant environment ideal for those who appreciate the beauty of nature, even in the midst of frequent showers.

September Temperature in San Blas

As September rolls into San Blas, Mexico, temperatures begin to reveal the warmth of the late summer, with nighttime lows resting comfortably at 23°C (74°F). The days are invitingly warm, averaging around 27°C (81°F), while peak afternoon temperatures can reach up to 32°C (91°F). This month sees a subtle but distinct prologue to the shift in seasons, as the tropical heat lingers, creating a perfect backdrop for beach activities and exploration. September's weather is doused in a delightful blend of warmth and the occasional refreshing breeze, ideal for those seeking both relaxation and adventure in this picturesque coastal paradise.

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

The chart illustrates September temperature patterns in San Blas, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec717172747780828281817773
Data source: Temperature data for San Blas 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 Blas

September in San Blas, Mexico, marks the culmination of the rainy season, with precipitation reaching a substantial 367 mm (14.5 in) over 27 days. This high amount underscores a significant trend of increasing rainfall that begins in June and peaks in August before tapering off in October. The incessant downpours throughout the month contribute to the region's lush landscapes, but they also signal the area's vulnerability to tropical storms. As the humid summer transitions to fall, the persistent rains of September serve as a reminder of nature's power and the important role that this season plays in replenishing the local ecosystem.

September Precipitation Trends in San Blas

The chart displays monthly precipitation patterns in San Blas, 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.
JanFebMarAprMayJunJulAugSepOctNovDec1718002117223426368190107
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in San Blas

As September unfolds in San Blas, Mexico, the humidity remains consistently high at 78%, a trend that echoes the preceding months of summer. Following a gradual increase from a low of 66% in April, the humidity peaks in July, only to slightly dip in October. This month marks the culmination of a humid season, mirroring the patterns observed in both August and June. Despite the warm, sticky air, September offers vibrant marine life and lush landscapes, making it a captivating time for visitors who embrace the tropical climate. As the year shifts towards the cooler fall months, the humidity does start to recede, yet September holds onto that sultry warmth a little longer, wrapping the region in its familiar embrace.

September Average Humidity in San Blas

This chart illustrates the average monthly humidity levels in San Blas, 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.
JanFebMarAprMayJunJulAugSepOctNovDec71%69%67%66%69%78%79%78%78%75%74%74%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in San Blas

In September, San Blas experiences a UV Index of 12, falling within the extreme exposure category, which means that sunburn can occur in as little as 10 minutes. This pattern of high UV levels continues from the peak months of April through August, illustrating a significant trend of intense sun exposure during the summer months. As the year transitions into October, the UV Index remains notably high at 11, further emphasizing the need for protective measures. For those planning outdoor activities, it’s crucial to stay informed about sun safety. For more details on UV Index trends in this beautiful coastal town, visit San Blas UV Index.

Maximum UV Index Levels in San Blas for September

The chart shows the monthly maximum UV Index (UVI) for San Blas 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.
JanFebMarAprMayJunJulAugSepOctNovDec810121313131212121197
Data source: San Blas 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 Blas

September in San Blas, Mexico, marks a gentle transition in sunshine, boasting 261 hours of sunlight—a delightful blend of warmth as summer winds down. While this still reflects a decent amount of sun, it does signify a gradual decline from the peak of 352 hours in May. The trend shows that as we move from the blazing days of summer into autumn, the hours of sunshine taper off, but not dramatically. With September exhibiting fewer sunny hours than August's 278, it suggests a shifting climate, inviting a refreshing ambiance perfect for enjoying the beauty and charm of San Blas. As the sunlight softens, it creates an inviting atmosphere for exploration, where vibrant sunsets replace the day’s heat and the community gears up for the upcoming harvest season.

Monthly Sunshine Duration in San Blas: September Highlighted

The September sunshine duration represents the total number of hours San Blas 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.
JanFebMarAprMayJunJulAugSepOctNovDec225h262h318h329h352h317h310h278h261h274h282h277h
Data source: San Blas September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Blas During September

In San Blas, Mexico, September offers a notably low chance of sunny weather, at just 26%. This trend follows a palpable decline in sunshine from the vibrant 80% in May to a mere 16% in August, illustrating the heart of the rainy season. As the summer months recede, the likelihood of sun improves modestly, peaking at 50% in October. While early fall may bring more clouds and rain, the gradual shift towards clearer skies offers hope for those seeking a balance of warmth and occasional sunshine.

Percentage of Sunny Days in September in San Blas

The chart illustrates the percentage of sunny days in San Blas 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 Blas experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec56%67%67%65%80%29%25%17%26%50%63%59%
Data source: San Blas September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Blas in September

As the summer fades into autumn, September in San Blas, Mexico, offers a delightful balance of 12 hours of daylight, echoing the lengthy sunlit days of the summer months. From January's 10 hours of daylight to May's peak of 13 hours, the trend shows a gradual increase in sunlight as the year progresses. Following the summer's zenith in June through August, where daylight remains plentiful, September marks a gentle transition back towards shorter days as October approaches. This consistent daylight duration not only enhances the region's vibrant landscapes but also provides ample opportunity for outdoor exploration, making September a splendid time to experience the natural beauty of San Blas.

Average Daylight Hours in San Blas for September

The chart illustrates the variation in daylight duration in San Blas throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 58m11h 26m12h 1m12h 39m13h 10m13h 24m13h 16m12h 49m12h 13m11h 36m11h 5m10h 49m
Data source: San Blas daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in San Blas

As September rolls into San Blas, Mexico, the average wind speed dips to 1.6 m/s (4 mph), marking one of the calmest months of the year. This slight reduction in wind intensity continues from August and reflects a broader trend, as the summer months generally experience lower wind speeds compared to the spring. With winds that gently sway the palm trees, September invites visitors to enjoy the tranquil beauty of the coastline, perfectly balancing warmth and serenity. As we transition into the fall, it's fascinating to observe how the varying wind patterns throughout the year paint a vivid picture of San Blas' climate, inviting both relaxation and inspiration amidst nature's unfurling canvas.

Average September Wind Speed in San Blas

The chart displays monthly wind speed patterns in San Blas, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.02.02.12.02.12.01.61.91.6 m/s1.71.81.9
Data source: San Blas September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in San Blas Compares to Other Months

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

In September, the weather is notably warmer, with average temperatures ranging from a minimum of 23°C (74°F) to a maximum of 32°C (91°F), accompanied by high humidity at 78% and significant precipitation of 367 mm (14.5 in) over 27 days. In contrast, January presents a much cooler climate, featuring a minimum temperature of 12°C (55°F) and an average of 22°C (71°F), while the maximum reaches 31°C (88°F). January experiences much less rainfall, with only 17 mm (0.7 in) of precipitation over just one day and lower humidity at 71%. For more detailed insights on the January weather, visit San Blas weather in January.

September weather is characterized by warmer temperatures, with averages around 27°C (81°F) and highs reaching up to 32°C (91°F). This month also sees significant rainfall, with approximately 367 mm (14.5 in) spread over 27 days, resulting in high humidity levels of 78%. In contrast, February offers a cooler climate, with average temperatures of 22°C (71°F) and maximums of 30°C (86°F). The month is relatively dry, experiencing only 18 mm (0.7 in) of precipitation over just one day and lower humidity at 69%. For those interested in the specifics of February's climate in San Blas, you can find more information here: San Blas weather in February.

In September, the weather is characterized by warm temperatures, with a minimum of 23°C (74°F) and an average of 27°C (81°F), reaching a maximum of 32°C (91°F). This month is also marked by significant rainfall, with a high precipitation total of 367 mm (14.5 in) over 27 rainy days and humidity levels averaging 78%. In contrast, March experiences milder temperatures, with a minimum of 15°C (59°F) and an average of 22°C (73°F), peaking at 29°C (85°F). Remarkably, March sees no precipitation and is dry throughout, accompanied by lower humidity levels averaging 67%. For a more detailed look at the weather during this month, visit San Blas weather in March.

September and April present quite contrasting weather conditions. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 32°C (91°F), with an average of 27°C (81°F). This month is characterized by high humidity at 78% and significant rainfall, totaling 367 mm (14.5 in) over 27 days. In stark contrast, April enjoys milder temperatures, with a minimum of 16°C (61°F) and a maximum of 30°C (86°F), averaging 23°C (74°F). Moreover, April is notably dry, featuring no rainfall over the month and lower humidity at 66%. For more detailed information, visit San Blas weather in April.

In September, the weather tends to be warmer and significantly wetter compared to May. Temperatures in September range from a minimum of 23°C (74°F) to a maximum of 32°C (91°F), with an average of 27°C (81°F). This month also sees considerable rainfall, totaling 367 mm (14.5 in) over 27 days, resulting in high humidity at 78%. In contrast, May experiences milder temperatures, with a minimum of 18°C (64°F) and a maximum of 31°C (87°F), averaging 25°C (77°F). Rain is virtually absent in May, with only 2 mm (0.1 in) recorded and no rainy days at all, contributing to a lower humidity level of 69%. For more detailed insights on May weather specifically, visit San Blas weather in May.

The weather in September tends to be slightly warmer, with average temperatures hovering around 27°C (81°F), similar to June, but with more extreme highs reaching up to 32°C (91°F). September also experiences significantly more precipitation, totaling 367 mm (14.5 in) over 27 days, compared to June's much drier conditions, which see only 117 mm (4.6 in) over just 11 days. Both months share similar humidity levels at 78%, but the increased rainfall in September makes it feel much more humid overall. For more specific details, you can check San Blas weather in June.

In comparing the weather between September and July, we see that September experiences slightly lower minimum and average temperatures, with a minimum of 23°C (74°F) and an average of 27°C (81°F), compared to July's minimum of 24°C (75°F) and average of 28°C (82°F). However, September also brings significantly higher precipitation, with 367 mm (14.5 in) spread over 27 days, whereas July has only 223 mm (8.8 in) during 23 days of rain. Both months exhibit high humidity levels, with September at 78% and July at 79%, leading to a similarly muggy atmosphere. For those interested in exploring the July climate in this region, San Blas weather in July provides detailed insights.

In comparing the weather between August and September, we see that September experiences slightly lower temperatures with a minimum of 23°C (74°F) and a maximum of 32°C (91°F), compared to August's minimum of 24°C (75°F) and maximum of 33°C (92°F). Although both months have a similar level of humidity at 78%, September receives less rainfall, recording 367 mm (14.5 in) over 27 days, whereas August has higher precipitation at 426 mm (16.8 in) also over 27 days. For more details on August weather, you can check San Blas weather in August.

September and October showcase a gentle transition in weather patterns. September experiences slightly higher temperatures, with a minimum of 23°C (74°F) and a maximum of 32°C (91°F), while October sees a similar minimum of 22°C (72°F) but a warmer maximum of 34°C (93°F). Precipitation also declines significantly from September’s 367 mm over 27 days to October's 190 mm across 16 days, indicating a decrease in rainy days. Humidity remains relatively high in both months, though slightly lower in October at 75% compared to September’s 78%. For a more detailed look at October weather, visit San Blas weather in October.

September and November showcase distinct weather patterns. In September, temperatures range from a minimum of 23°C (74°F) to a maximum of 32°C (91°F), with an average of 27°C (81°F). This month is characterized by significant rainfall, totaling 367 mm (14.5 in) across 27 days, contributing to a high humidity level of 78%. In contrast, November experiences more temperate conditions, with a minimum temperature of 18°C (64°F) and an average of 25°C (78°F), yet it can still reach up to 32°C (89°F). The precipitation drops dramatically to just 9 mm (0.4 in) over a mere 1 day, resulting in a slightly lower humidity of 74%. These changes create a noticeable transition from the wet, humid climate of September to the drier, more comfortable conditions of November. For more detailed information, check out San Blas weather in November.

In September, temperatures are warmer with a minimum of 23°C (74°F), averaging 27°C (81°F), and peaking at 32°C (91°F). The month also experiences significant rainfall, with an average of 367 mm (14.5 in) over 27 days, leading to a high humidity level of 78%. Conversely, December brings much cooler temperatures, with a minimum of 15°C (59°F) and an average of 23°C (73°F), while the maximum reaches 30°C (85°F). December sees a dramatic decrease in precipitation, with only 7 mm (0.3 in) over just 1 day and humidity at 74%. For more details, you can refer to San Blas weather in December.

Compare San Blas's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in San Blas

As September arrives in San Blas, it ushers in a distinct shift in the weather, characterized by higher temperatures and increased humidity compared to other months. With maximum temperatures reaching a sultry 32°C and a considerable amount of rainfall, this month stands out with approximately 27 days of precipitation. The air feels heavy with an average humidity of 78%, creating a tropical atmosphere that’s both vibrant and challenging. Despite the rain, the lush landscapes thrive, making September a unique time to experience the lush beauty of San Blas. For a deeper understanding of how September compares to the rest of the year, explore our detailed San Blas Climate guide.