In September, Cancun has an average daily high temperature of 89 to 90 degrees Fahrenheit, and an average daily low temperature of 76 to 77 degrees Fahrenheit. The weather is slightly cooler than during the summer months and noticeably warmer than during the winter. September tends to be the rainiest month of the year in Cancun.
Cancun receives an average of 23 centimeters of rain in September. September is in the middle of Cancun's rainy season, which runs from May to October.
Cancun's highest sea temperatures occur between July and October. During each of these months, the average sea temperature is 84 degrees Fahrenheit, a comfortable temperature for swimming.
September is also part of Cancun's hurricane season. In addition to more frequent rains, dangerous storms may occur at this time of year. People in Cancun must be prepared to stay inside and find a safe place of refuge if there is a storm forecast.
Since Cancun's September weather is less desirable than weather at other times of year, hotels may be less crowded and cheaper. It is still possible to enjoy the beach at this time of year since there are some sunny days. Even though Cancun has a rainy season, it averages 240 sunny days each year.