What is the proper name of a city that has unpredictable weather?
Most - climate - is predictable. Climate is long term weather, so it's 'evened out' or 'averaged over time', so it's more predictable. Does the question involve itself with 'a city' or 'unpredictable'?
If you're in Denver and don't like the weather, wait a minute.
No such thing as unpredictable!