Summer and early Autumn. Only time of the year when it's actually possible to get clear skies in Melbourne.

Winter is a write-off, approaching Macquarie Island levels of cloudiness and daily drizzle for weeks on end, not to mention skin-penetrating wind straight off the tropical 10C waters of Port Phillip Bay and the Southern Ocean, and spring is like a crappy sequel to a crappy movie.
Oh, and in summer atleast I can talk my dog for a walk beyond the concrete path as I don't have to fear sinking shin-deep into mud