Live-aboard Coral Sea from Cooktown to Cairns

Dear down-under friends,

From the 16th of november I'm sailing 7 days the Coral Sea to dive the
Ribbon Reef and Cod hole.

Now at this moment in the Caribic hurricanes are going on, and also cyclones
in the environs of Japan / China, can I expect such a type of weather too on
the Coral Sea.

I heard a lot about the underwater-life on the GBR. Is it safe to dive
overthere.
What are the dangereous creatures, people told me about a blue octopus and
seasnakes.

Okay I know the principle, don't touch anything, but I like to have knowlege
about agressive and/or poisonous animals.

Thanks for your info

Henk,
The Netherlands