Stay in Perth vs. Fremantle?

Mid March can still be pretty warm up north and perhaps too hot for Coral Bay (Exmouth, the nearest town has a dgree Celsius range of 23-36 at that time of the year but has been known to hit the mid 40s) . It can be done in a (long) day but most people break in Carnarvon which you'd get to about 5ish if you leave Perth early and then take another half day to get to Coral Bay. You don't really want to be driving at night as the risk of hitting roos, goats or cattle, all of which abound on the roads up there, is pretty high. A cyclone would be unlucky but possible at that time of year. A good stop on the way is Northampton which has some nice historic buildings and would be attainable by lunch time.
Personally I'd head south as distances are shorter and the weather will certainly be better. Apart from vineyards and good dining there is some good timber country and short through to multi day walks easily accessible. Try Pemberton for the world's tallest fire observation platform (located on top of a vast tree and not for the fainthearted - https://en.wikipedia.org/wiki/Gloucester_Tree)
Freo has a pretty good train service into Perth so it probably doesn't matter much where you stay, suggest go for cost and quality of accommodation and closeness to public transport.

Great & helpful info about weather and north vs. south, stay in Fremantle vs. Perth. Thanks so much. Also, does cyclone mean lots of rain (like our hurricanes in U.S., typhoons in Taiwan) or just wind...not sure what sort of measures one takes for riding out a cyclone...bad to be in a car? Hot by the ocean sounds really nice to us right now being in grey, rainy Taipei, but maybe we'd melt in that heat!

A cyclone can be pretty variable and depends where you are in relation to where it crosses land. If near the epicentre you are talking about evacuation into a regional strongpoint of which there are quite a few so unlikely you'd have to ride it out in a car. Most towns up there are now cyclone worthy but I've been through one up there that wiped out 2/3 of the town. More likely though that you get an awful lot of rain and stuck in your hotel/tent with perhaps a fair bit of local flooding and roads closed for several days. If you had a choice I'd recommend leaving it to the WA winter and then heading north and you could then do Karajini as well as Ningaloo which makes a pretty good 10-14 day road trip.

It's a great time of year to explore the south west and south coast of WA. Margaret River, Pemberton, Denmark and Albany are all at their best.

Stay in Fremantle, no question as it is much nicer and more interesting than Perth city, with plenty to see and do within mostly walkable distances - you can pop over to Rottnest Island too, for a day or two.

Have you looked at a map to see how far Coral Bay is? Put it this way, most people who go there, probably fly unless you have plenty of time for slow travel. You can fly to Exmouth (Learmonth) and hire a car there and fly back - it's probably the best way to do it.....

Otherwise the south west as has been said above, is wonderful and the right time of the year to visit - and very different from Taipei.

Thanks for the cyclone information. Good to have a local's knowledge of weather and how to deal with it. Can't change our dates so we'll have to consider all those factors. Thanks so much!

This is why I love this forum -- the details a foreigner just doesn't get are made clear by folks in the know! Thanks so much. I'll check into Exmouth flights/car rentals...& Fremantle it is!

'Stay in Fremantle, no question as it is much nicer and more interesting than Perth city' But what about Elizabeth Quay? (in Perth joke)

Thanks all for the input. Very curious about Elizabeth Quay joke...please explain. We decided to head up to Ningaloo because the idea of seeing marine critters there and in Shark's Bay too tempting to resist. Hours on hotel sites lead me to decide on first night stop in Port Denison-Dongara. Accomodations don't look so great in Shark Bay Area -- would you advise staying two days in Kalbarri where accomodations better & to visit national park, then visit Shark Bay Area just briefly, (many online reviews felt Monkey Mia, though personally would love to see those Dolphins!) with overnight in Coral Bay? Not sure how to divide our time here, seems to be dependent on available lodging, but if you have any suggestions on where would be better for renting kayaks, nice beach hikes, snorkeling, would love to hear your opinions...We are for sure spending two nights in Ningaloo/Exmouth before returning south.