The Vatican climate is the same as Rome's; a temperate, Mediterranean climate with mild, rainy winters from September to mid-May and hot, dry summers from May to August.
Vatican City is a city state that came into existence in 1929. It is therefore to be clearly distinguished from the Holy See, which already was in existence for many centuries before that date.
Vatican City State is a landlocked sovereign city-state whose territory consists of a walled enclave within the city of Rome, the capital city of Italy.