September Weather in Isla Mujeres, Mexico

Last updated: April 22, 2025

In Isla Mujeres, Mexico, September welcomes warm tropical weather, with maximum temperatures reaching up to 30°C (86°F) and an average of about 28°C (83°F). The minimum temperatures hover around 25°C (77°F), providing a comfortable climate ideal for beachgoers. However, visitors should be prepared for increased rainfall, as the island experiences approximately 117 mm (4.6 in) of precipitation over 19 days, making humidity levels rise to a moderate 76%. Despite the showers, the warm temperatures and vibrant atmosphere make September a unique time to explore this beautiful Caribbean destination.

September Temperature in Isla Mujeres

In September, Isla Mujeres experiences pleasant tropical warmth, with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 30°C (86°F). The average temperature maintains a steady 28°C (83°F), aligning perfectly with the warmer months leading up to it. This month signals a delicate transition as summer drifts into fall, yet the island remains vibrant, encouraging visitors to bask in the sun, snorkel in the crystal-clear waters, and explore its stunning landscapes. As you step into September, expect balmy days and sultry nights, creating an enticing atmosphere for both relaxation and adventure.

September Weather in Isla Mujeres: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Isla Mujeres, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec767778798182838382817978
Data source: Temperature data for Isla Mujeres 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 Isla Mujeres

In September, Isla Mujeres experiences a noticeable uptick in precipitation, with 117 mm (4.6 in) of rain falling over approximately 19 days. This peak in rainfall marks the transition into the wetter season, following the relative dryness of the summer months. While May and August also see significant rainfall, September stands out for its persistence, contributing to the lush, vibrant landscapes of the island as it heads into autumn. The increase in precipitation is part of a broader trend leading into October, which averages an even higher 214 mm (8.4 in), emphasizing that the latter part of the year is characterized by more regular rain, often refreshing the air and paving the way for lush growth.

September Precipitation Trends in Isla Mujeres

The chart displays monthly precipitation patterns in Isla Mujeres, 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.
JanFebMarAprMayJunJulAugSepOctNovDec623021341181664410011721411873
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Isla Mujeres

In September, humidity in Isla Mujeres, Mexico remains consistent, hovering around 76%. This level is a continuation of the trend observed over the previous several months, where humidity typically stabilizes in the mid-seventies from May through August. As summer transitions into fall, the slightly higher levels seen at the start of the year—peaking at 79% in January—ease into this more moderate humidity, which stays steady into October. Interestingly, the humidity then begins to rise again as the year winds down, hinting at seasonal shifts. Overall, September offers a delightful balance of warmth and comfort, making it a pleasant time to experience the lush landscapes and vibrant culture of this tropical paradise.

September Average Humidity in Isla Mujeres

This chart illustrates the average monthly humidity levels in Isla Mujeres, 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.
JanFebMarAprMayJunJulAugSepOctNovDec79%78%76%76%75%76%76%76%76%76%78%80%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Isla Mujeres

As September rolls into Isla Mujeres, the UV Index remains a robust 12, a mark of the extreme exposure category. Similar to the preceding months of June and July, outdoor enthusiasts should be particularly cautious, as skin can burn in a mere 10 minutes of direct sun. This trend of high UV levels has been consistent since March, where a steady escalation began, peaking in April and May before maintaining that intensity through the summer months. With the UV Index gradually tapering off in October to 11, it serves as a reminder to embrace sun safety precautions during your beach outings. For more detailed information, check the Isla Mujeres UV Index.

Maximum UV Index Levels in Isla Mujeres for September

The chart shows the monthly maximum UV Index (UVI) for Isla Mujeres 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.
JanFebMarAprMayJunJulAugSepOctNovDec810121313131212121187
Data source: Isla Mujeres 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 Isla Mujeres

September in Isla Mujeres, Mexico, offers an inviting blend of sun-soaked days, boasting 317 hours of sunshine. As summer winds down, this month stands out as a bridge between the peak brightness of July and August, which each enjoyed over 330 hours of radiant light. Following a high in May with 345 hours, the consistent warmth of September maintains a pleasant glow, making it an ideal time for both relaxation and adventure. With daylight gradually dipping toward autumn yet still generous, visitors can revel in the beauty of this vibrant paradise before the cooler months set in. Soak up the sun, savor the mesmerizing sunsets, and enjoy the lasting warmth of this coastal gem!

Monthly Sunshine Duration in Isla Mujeres: September Highlighted

The September sunshine duration represents the total number of hours Isla Mujeres 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.
JanFebMarAprMayJunJulAugSepOctNovDec232h283h324h329h345h306h346h333h317h302h297h295h
Data source: Isla Mujeres September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Isla Mujeres During September

September in Isla Mujeres, Mexico, marks a transition as summer begins to wane, bringing with it a lower likelihood of sunny weather. With a sun probability of only 33%, this month stands out as one of the cloudier times of the year. Following the summer months of June (29%) and July (60%), September's chances drop significantly, suggesting a shift towards the rainy season. Yet, with the vibrant azure waters and lush landscape, the occasional sunshine still graces the island, offering a balance of mild skies and warm breezes. Visitors should embrace the unpredictability, as even with the clouds, Isla Mujeres’ charm remains irresistible.

Percentage of Sunny Days in September in Isla Mujeres

The chart illustrates the percentage of sunny days in Isla Mujeres 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 Isla Mujeres experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec39%66%70%62%55%29%60%52%33%52%49%62%
Data source: Isla Mujeres September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Isla Mujeres in September

In Isla Mujeres, Mexico, the month of September enjoys approximately 12 hours of daylight, mirroring the earlier months of March and April. This marks a gradual transition from the longer days of summer, where sunlight reaches its peak at 13 hours from May to August. As the year progresses towards the end of September, daylight begins to wane, leading into October with just 11 hours. The trend highlights a rhythmic ebb and flow of sunlight, where the vibrant days of summer gradually give way to the cooler, shorter days of fall, offering a delightful balance for both locals and visitors alike.

Average Daylight Hours in Isla Mujeres for September

The chart illustrates the variation in daylight duration in Isla Mujeres throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 59m11h 26m12h 1m12h 38m13h 8m13h 23m13h 15m12h 48m12h 13m11h 37m11h 6m10h 51m
Data source: Isla Mujeres daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Isla Mujeres

In September, the winds in Isla Mujeres, Mexico gently ease into a more tranquil rhythm, with an average speed of just 5.0 m/s (11 mph). This seasonal shift marks a notable decline from the breezier months of spring and summer, where winds often reached up to 7.0 m/s (16 mph) in April. As the summer heat gives way to the autumn breeze, September's calmness becomes ideal for relaxing beach days and leisurely water activities, signaling a perfect time for visitors to savor the tranquil beauty of this island paradise. As the year progresses, winds tend to decrease further, hinting at a quieter transition into the cooler months ahead.

Average September Wind Speed in Isla Mujeres

The chart displays monthly wind speed patterns in Isla Mujeres, 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.
JanFebMarAprMayJunJulAugSepOctNovDec6.26.96.87.06.66.25.15.65.0 m/s4.65.46.1
Data source: Isla Mujeres September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Isla Mujeres Compares to Other Months

The weather in Isla Mujeres 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 Isla Mujeres and find detailed weather information for every month.

In September, the weather is characterized by warmer temperatures, with minimums reaching 25°C (77°F) and averages around 28°C (83°F), whereas January sees cooler conditions with minimums dropping to 20°C (69°F) and an average of 24°C (76°F). September also experiences more rainfall, totaling 117 mm (4.6 in) over 19 days, compared to January's 62 mm (2.4 in) spread across 12 days. Despite the slight increase in humidity in January at 79%, September’s humidity is still high at 76%, contributing to a more oppressive feel in the air. For more specific details on January weather, you can check this link: Isla Mujeres weather in January.

In comparing the weather between September and February, September tends to be warmer and significantly wetter. Average temperatures in September range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 28°C (83°F). It also experiences substantial rainfall, totaling 117 mm (4.6 in) over 19 days, alongside relatively high humidity at 76%. In contrast, February offers milder conditions, with temperatures ranging from a low of 21°C (70°F) to a high of 27°C (81°F) and a lower average of 25°C (78°F). The precipitation in February is considerably reduced at 30 mm (1.2 in) spread over just 10 days, with slightly higher humidity at 78%. For more specific details on February's climate, you can check Isla Mujeres weather in February.

In comparing the weather patterns of September and March, September tends to be notably warmer and wetter. The average temperature in September hovers around 28°C (83°F), reaching a maximum of 30°C (86°F), while March is slightly cooler, with average temperatures around 25°C (78°F) and highs of 27°C (82°F). Additionally, September experiences significantly higher precipitation, accumulating 117 mm (4.6 in) over 19 days, compared to March's modest 21 mm (0.8 in) spread over just 5 days. Both months share the same humidity level of 76%, but September's increased rainfall makes it feel more humid overall. For a detailed look at March weather specifics, you can check Isla Mujeres weather in March.

When comparing the weather in September and April, it is clear that September tends to be warmer and wetter. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 28°C (83°F). The month also sees significant rainfall, with 117 mm (4.6 in) of precipitation over 19 days. In contrast, April is slightly cooler, with temperatures ranging from 23°C (73°F) to a maximum of 28°C (83°F) and an average of 26°C (79°F). This month experiences much less rainfall, totaling only 34 mm (1.3 in) over 5 days. Both months share a humidity level of 76%, making them quite sticky. For more detailed information on the weather in April, you can refer to Isla Mujeres weather in April.

When comparing the weather in September and May, both months exhibit warm temperatures, but September tends to be slightly hotter. In September, the minimum temperature is around 25°C (77°F), with an average of 28°C (83°F) and a maximum of 30°C (86°F). In contrast, May offers a bit cooler experience, featuring a minimum of 24°C (75°F), an average of 27°C (81°F), and a maximum of 29°C (84°F). Both months experience similar levels of precipitation, with September receiving 117 mm (4.6 in) over 19 days, while May has a comparable 118 mm (4.6 in) spread over 16 days. Humidity levels are also quite close, with September at 76% and May slightly lower at 75%. For more detailed information about May weather, visit Isla Mujeres weather in May.

When comparing the weather in September and June, both months exhibit similar temperature profiles, with a minimum of 25°C (77°F), an average around 28°C (83°F), and a maximum of 30°C (86°F) in September and slightly lower at 29°C (85°F) in June. However, September sees less rainfall than June, with 117 mm (4.6 in) over 19 days compared to June's 166 mm (6.5 in) over 18 days. Both months maintain the same humidity level of 76%, indicating a consistently humid atmosphere. For those looking for more detailed insights into June's weather specifically, Isla Mujeres weather in June provides further information.

When comparing the weather in September to July, we see some notable differences despite similar temperature averages. Both months have a minimum temperature of around 25°C (77°F) and an average temperature of 28°C (83°F), but September tends to be slightly warmer with a maximum of 30°C (86°F) compared to July's 29°C (85°F). A significant contrast lies in precipitation, as September experiences much higher rainfall at 117 mm (4.6 in) over 19 days, while July is much drier, receiving only 44 mm (1.7 in) across just 10 days. Interestingly, the humidity remains consistent at 76% for both months, making them feel equally tropical. For a more detailed look at July weather, check out Isla Mujeres weather in July.

In comparing the weather between September and August, we see that both months maintain similar average and maximum temperatures, hovering around 28°C (83°F) and 30°C (86°F) respectively. However, September experiences slightly cooler minimum temperatures, dropping to 25°C (77°F) compared to August's minimum of 26°C (79°F). Another notable difference is the increase in precipitation in September, with 117 mm (4.6 in) over 19 days, while August has less rain at 100 mm (3.9 in) over 14 days. Both months share the same humidity level of 76%, creating a consistently warm and sticky climate. For more details on the weather in August, you can check Isla Mujeres weather in August.

In comparing the weather of September and October, we see a slight decline in average temperatures—September maintains an average of 28°C (83°F) while October averages around 27°C (82°F). However, October experiences an increase in precipitation, with 214 mm (8.4 in) falling over 23 days, compared to September's 117 mm (4.6 in) across 19 days. Notably, humidity remains constant at 76% for both months. For more details on the specific weather conditions in October, you can visit Isla Mujeres weather in October.

September and November display a subtle shift in weather conditions. In September, the temperatures range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 28°C (83°F). This month also sees higher precipitation, with 117 mm (4.6 in) over 19 days and a humidity level of 76%. In contrast, November presents slightly cooler temperatures, with a minimum of 23°C (73°F) and a maximum of 29°C (84°F), averaging 26°C (79°F). Precipitation remains comparable, totaling 118 mm (4.7 in) over 16 days, but the humidity increases to 78%. For more detailed insights on November weather, you can check Isla Mujeres weather in November.

In September, the weather tends to be warmer, with average temperatures reaching around 28°C (83°F) and maximums peaking at 30°C (86°F). This month also sees higher precipitation levels, averaging 117 mm (4.6 in) over 19 days, resulting in a humidity level of 76%. In contrast, December brings a slight cooling, with average temperatures dropping to 25°C (78°F) and maximums at 28°C (83°F). Rainfall is reduced significantly to 73 mm (2.9 in) over 13 days, coupled with a slightly higher humidity level of 80%. For a more detailed look at December weather, you can visit Isla Mujeres weather in December.

Compare Isla Mujeres's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Isla Mujeres

As September rolls into Isla Mujeres, the weather becomes distinctly more humid and wet compared to the drier months of summer. With an average temperature that hovers around a pleasant 28°C, it's still warm enough for beachgoers, although the increased precipitation—with nearly two-thirds of the month seeing rain on average—can put a damper on outdoor plans. The lush greenery flourishes under these conditions, creating a vibrant landscape that's perfect for exploration. If you’re planning your visit, be sure to check out more about the seasonal changes and what to expect by visiting Isla Mujeres Climate.