Effects of high humidity. Humidity is considered too high when its level goes above 45% - 50%, sometimes as high as 80% and up. High humidity can be especially dangerous when combined with high temperature - as mentioned above, high humidity disrupts the body's ability to cool itself, which may lead to a heat stroke.
The average sea surface temperature in April 2017 for Cancun was 84.0Â°F. The maximum and minimum values were 83.0Â°F and 85.4Â°F respectively.
Summer Weather in Cancun The wet season in Cancun is much hotter than the dry season, primarily due to the increased humidity caused by intense rainfall. During this season, average temperatures range from 27Â°C (81Â°F) in May up to of 28Â°C (82Â°F) in June, July, August and September.