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.
Every month, the temperature at Cancun usually drops to 75 Â°F (24 Â°C) or lower. Generally the Caribbean coast city gets no colder than 49 Â°F (9.5 Â°C). February, March and April bring the year's driest weather to Cancun, with averages of just 5 days and 1.6 inches (42 millimetres) of rain a month.