yes. I’m not sure how worried I would be about this threatened rain

the only part I would be truly concerned about is the blue mountains, a) because I personally think they’re a bit overrated and b) because they are a bit more weather dependent.

the various walks/ferries around Sydney I would still do, ideally early-ish in the mornings to miss weather. Have some museums and galleries lined up to do when the weather closes in

canberra is good and semi-nearby for lots of museums, important landmarks and galleries, could be an option for a “couple of days” trip- although the weather there looks to be even worse than Sydney