Weather in Cancun in November. The average maximum daytime temperature in Cancun in November is a warm 29°C (84°F) with high heat & humidity. There are usually 6 hours of bright sunshine each day, which represents 57% of the 11 hours of daylight. The average sea temperature in and around Cancun in November is 28°C (82°F). Expect 91mm (3.6 inches) of rainfall across the whole of November with 8 days with some rain falling. Maximum UV levels will be very high (8 UV index) at midday when the skies are clear.