The Isle of Wight, and in particular the South East corner between Ventnor and Sandown, enjoys the sunniest weather of anywhere in Great Britain.  The average weather for Ventnor, Shanklin and Sandown is 5.1 hours per day across the whole year as opposed to inland Hampshire with 4.1 hours per day.

Driest months	April, May, July
Wettest months	January, November, December
Sunniest months	May, July, August
Dullest months	January, November, December
Warmest months	June, July, August
Coldest months	January, February, December

Mean maximum temperatures in the warmest month are 21.5ºC in Newport - the inland county town of the Isle of Wight and 19ºC at St Catherine's Point - the southern most point of the Island.

 

source - Medina Valley Centre