Last updated: April 22, 2025
September in San Blas, Mexico, offers a dynamic weather experience characterized by warm temperatures, with maximums soaring up to 40°C (104°F) and averages maintaining a comfortable 29°C (84°F). Nights cool down to a pleasant minimum of 20°C (69°F), providing a refreshing contrast to the daytime heat. However, this month also brings significant moisture, with total precipitation reaching 112 mm (4.4 in) over approximately 15 days, and an average humidity level of 78%. While visitors can expect occasional rain, the tropical climate and lush surroundings create a vibrant and inviting atmosphere, perfect for exploring the beauty of this coastal gem.
As September rolls into San Blas, Mexico, the temperatures reflect the tail end of a vibrant summer, with the average temperature resting at a comfortable 29°C (84°F). Nighttime lows dip to a milder 20°C (69°F), offering a pleasant reprieve from the day's warmth, which can soar to a maximum of 40°C (104°F). This month's temperatures continue the trend of warmth established in the preceding summer months, slightly cooler than the peak heat of July and August but still inviting for beachgoers and adventurers alike. The transition into autumn is subtle, reminding visitors that while the days may be hot, the evenings still beckon with cooler charms perfect for exploring local culture and enjoying the stunning coastal views.
September marks a significant point in San Blas, Mexico's precipitation pattern, with an impressive 112 mm (4.4 in) of rainfall over 15 days. This month continues the trend established in the preceding summer months, where August also delivered substantial rain at 133 mm (5.2 in). The steady increase in precipitation since June, which saw only 19 mm (0.7 in), indicates a shift into the region’s wetter season, creating a lush landscape. Interestingly, after a dry spell in spring with 0 mm in both April and May, the monsoons have certainly returned with vigor, bringing with them both the challenges and the beauty of tropical weather. As October approaches, the rainfall is expected to dip again, but September's robust levels provide a vibrant backdrop to the region's lush surroundings.
In September, San Blas, Mexico, experiences a notable rise in humidity, maintaining a level of 78%, which is consistent with the high humidity recorded in August. This peak marks one of the highest points of the year, following a gradual increase since the cooler, drier months of early spring. As the year progresses, humidity fluctuates, starting at 70% in January and dipping to a low of 58% in April before rising again in the summer months. Following September, humidity slightly decreases to 75% in October, reminding us that while the tropical climate brings intense summer heat, the transition into autumn still holds onto that signature oceanic moisture.
As September rolls in, San Blas, Mexico, maintains its extreme UV Index of 12, necessitating vigilant sun protection with a burn time as short as 10 minutes. This trend from the summer months, where the UV Index also peaked at 12, indicates a continuation of intense sun exposure during this time of year. Travelers and locals alike should be mindful of their outdoor activities, safeguarding their skin against harmful rays. As the year transitions into the fall, the UV levels will gradually decline, dropping to a very high index in October. For more detailed insights into the UV Index throughout the year, you can check San Blas UV Index.
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As September rolls in, San Blas, Mexico basks in a delightful 288 hours of sunshine, making it a perfect blend of warmth and vitality. Following the sun-soaked peak of May, which boasts an impressive 362 hours, the month sees a gradual decline in daylight, yet still embraces an abundance of bright days. The transition from the summer's high basking hours reveals a natural rhythm to the seasons — while it's less than the summer months, September's sunshine is still plentiful, especially compared to the cooler months ahead, like November and December, which offer just 269 and 265 hours respectively. This gradual waning of sunlight signifies a shift towards autumn, inviting visitors to enjoy the lingering warmth and vibrant landscapes before the chill sets in.
In San Blas, Mexico, the month of September sees a 50% chance of sunny weather, marking a transitional period as summer gives way to autumn. This probability is notably higher than the preceding months of July and August, which experience significantly lower sunshine rates at 44% and 35% respectively. As September progresses, the likelihood of clearer skies begins to mirror the sunniest months earlier in the year, such as May with its impressive 79% chance of sun. Overall, while September may not boast the highest levels of sunshine in comparison to other months, it offers a promising balance of sun and respite from the summer heat, making it an appealing time to visit.
In September, San Blas enjoys 12 hours of daylight, marking a gentle transition as the summer days gradually wane. This month is part of a broader trend where daylight peaks in the summer months of May, June, and July with a generous 13 hours, before tapering off in the fall. As the year progresses towards the cooler months, daylight duration gradually decreases to 11 hours in October and 10 hours by November. September strikes a harmonious balance, providing ample sunlight to explore the region's stunning landscapes and vibrant culture, making it a perfect time for both adventure and relaxation.
As September wraps up the summer season in San Blas, Mexico, the winds begin to settle into a gentle rhythm, averaging a mild 1.6 m/s (4 mph). This marks a continuation of the calming trend seen since mid-summer, when wind speeds dipped from the higher breezes of earlier months. Both July and August experienced similarly soft gusts, reflecting a slow transition from the peak summer heat to the more temperate fall climate. Although September's winds are less formidable, they create an inviting atmosphere, ideal for leisurely beach walks and embracing the serene beauty of coastal life. As the year progresses toward autumn, the winds are poised to gradually increase, hinting at the subtle but distinct shifts that characterize San Blas throughout the seasons.
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.
September and January offer stark contrasts in weather patterns. In September, temperatures range from a minimum of 20°C (69°F) to a maximum of 40°C (104°F), with an average of 29°C (84°F). The month also experiences considerable rainfall, totaling 112 mm (4.4 in) over about 15 days, accompanied by high humidity at 78%. In contrast, January features significantly cooler temperatures, with a minimum of 3°C (38°F), an average of 18°C (65°F), and a maximum of 35°C (95°F). Precipitation is minimal, with just 10 mm (0.4 in) occurring over about 1 day, and humidity is slightly lower at 70%. For a more detailed look at January weather, check out San Blas weather in January.
In September, temperatures soar, with a minimum of 20°C (69°F) and an average high of 29°C (84°F), occasionally reaching up to a sweltering 40°C (104°F). This month also brings significant rainfall, with 112 mm (4.4 in) of precipitation over 15 days, resulting in a humid atmosphere at 78%. In contrast, February offers much cooler conditions, with a minimum temperature of 4°C (39°F) and an average high of 19°C (66°F), peaking at 34°C (94°F). Rainfall is minimal in February, totaling just 17 mm (0.7 in) over only 2 days, and humidity levels are slightly lower at 67%. For more detailed weather insights, check out San Blas weather in February.
September and March present contrasting weather conditions. In September, the temperatures range from a minimum of 20°C (69°F) to a scorching maximum of 40°C (104°F), with an average of 29°C (84°F). This month also experiences significant rainfall, accumulating 112 mm (4.4 inches) over approximately 15 days, and high humidity levels at 78%. Conversely, March offers a much cooler climate, with temperatures ranging from a minimum of 5°C (42°F) to a maximum of 36°C (98°F), and an average of 21°C (70°F). The precipitation is minimal at just 5 mm (0.2 inches) over 1 day, coupled with lower humidity at 62%. For a detailed look at March weather specifically, you can visit San Blas weather in March.
When comparing the weather in September and April, significant differences emerge. September experiences higher temperatures, with a minimum of 20°C (69°F) and an average of 29°C (84°F), occasionally peaking at 40°C (104°F). It is also characterized by considerable rainfall, with 112 mm (4.4 in) of precipitation over 15 days and a humidity level of 78%. In contrast, April is much milder, featuring a minimum temperature of 9°C (48°F) and an average of 24°C (75°F), with a maximum of 38°C (100°F). Notably, April has no recorded precipitation, resulting in a dry climate and lower humidity at 58%. For more detailed information on April weather, check out San Blas weather in April.
September and May exhibit distinct differences in weather patterns. September boasts a warmer average temperature of 29°C (84°F) and can experience highs reaching up to 40°C (104°F), alongside significant rainfall totaling 112 mm (4.4 in) over approximately 15 rainy days, contributing to a humid environment with 78% humidity. In contrast, May has a milder average temperature of 26°C (80°F) with similar maximum temperatures of 40°C (105°F), but it stands out for its dry conditions, recording no precipitation throughout the month. The humidity during May is also lower at 59%, offering a comfortable climate. For more insights, visit San Blas weather in May.
In comparing the weather between September and June, we observe notable differences in temperature, precipitation, and humidity levels. September typically boasts a minimum temperature of 20°C (68°F) and an average of 29°C (84°F), with a maximum reaching up to 40°C (104°F). In contrast, June features slightly lower minimum temperatures at 17°C (64°F) and a comparable average of 30°C (86°F), peaking at a hotter 42°C (107°F). Precipitation is considerably higher in September, with 112 mm (4.4 in) falling over 15 days, while June experiences a much drier climate, with only 19 mm (0.7 in) over just a single day. Additionally, humidity levels in September are elevated at 78%, compared to June's 64% humidity. For more detailed insights, you can check this link for San Blas weather in June.
In comparing the weather of September and July, both months experience high temperatures, but September tends to have slightly cooler average temperatures, with a minimum of 20°C (68°F) compared to July's minimum of 23°C (73°F). The average temperature in September is 29°C (84°F), while July is warmer at 31°C (87°F). Both months can reach maximum temperatures of around 40°C (104°F to 105°F). Rainfall is more pronounced in September, with 112 mm (4.4 in) of precipitation over 15 days, compared to July's 90 mm (3.6 in) over 13 days. Additionally, September has a higher humidity level at 78%, compared to July's 74%. For more detailed information, you can check San Blas weather in July.
In comparing the weather conditions of September and August, we see some notable differences. September's minimum temperature is slightly lower at 20°C (69°F), while August maintains a higher minimum of 23°C (74°F). The average temperatures are quite comparable, with September averaging 29°C (84°F) and August at 30°C (87°F), yet August peaks at a higher maximum temperature of 42°C (107°F) compared to September’s 40°C (104°F). Regarding precipitation, September experiences a total of 112 mm (4.4 in) over 15 days, which is less than August's 133 mm (5.2 in) over the same number of days. Interestingly, both months share an identical humidity level of 78%. For a detailed look at the weather specifics in August, you can check San Blas weather in August.
September weather is characterized by warmer temperatures and higher humidity, with minimums around 20°C (69°F) and average highs reaching up to 40°C (104°F). Additionally, the month sees significant rainfall, with a total of 112 mm (4.4 in) spread over 15 days. In contrast, October experiences a notable drop in minimum temperatures to 11°C (52°F), although the average remains relatively stable at 28°C (83°F), with maximums peaking at a slightly higher 42°C (107°F). Rainfall decreases dramatically to just 19 mm (0.7 in) over only 3 days, and humidity levels slightly dip to 75%. For more detailed weather information, check out San Blas weather in October.
In September, the weather features significantly warmer temperatures, with a minimum of 20°C (69°F) and an average high of 29°C (84°F), soaring to a maximum of 40°C (104°F). The month is also marked by higher humidity at 78% and considerable rainfall, totaling 112 mm (4.4 in) over approximately 15 days. In contrast, November experiences much cooler temperatures, with a minimum of 9°C (49°F), an average of 24°C (75°F), and a maximum reaching 39°C (103°F). Precipitation drops to just 30 mm (1.2 in) over only 2 days, and humidity decreases slightly to 74%. These differences highlight the transition from the heat of September to the milder conditions of November. For specific insights on this month, check out San Blas weather in November.
In September, weather conditions are characterized by significantly higher temperatures, with minimums around 20°C (69°F) and maximums reaching up to 40°C (104°F), making it quite hot overall with an average temperature of 29°C (84°F). This month also experiences considerable rainfall, averaging 112 mm (4.4 in) over 15 days, accompanied by high humidity levels of 78%. In contrast, December sees a much cooler climate, with temperatures dipping to a minimum of 4°C (40°F) and averaging only 19°C (67°F), while maximums reach 34°C (94°F). The precipitation is minimal in December, with only 11 mm (0.4 in) over just one day and humidity slightly lower at 72%. For more details on December weather, check San Blas weather in December.
As September unfolds in San Blas, the weather presents a striking contrast to the drier months that precede it. The temperatures remain warm, with average highs around 29°C (84°F), but the arrival of the rainy season brings an increase in humidity and over a week of rain that can challenge outdoor plans. With 15 days of precipitation amounting to 112 mm (4.4 in), it's essential for visitors to prepare for the occasional downpour which is a hallmark of this month. Despite the rain, September retains a tropical charm, making it a unique time to experience the lush landscapes. For more insights into the weather patterns, check out San Blas Climate.