It`s pretty predictable what will happen.
Iran launches some ballistic missiles, probably targeting greater Tel-Aviv. Most of the missiles will be intercepted by Hetz, but some get through nevertheless.
Galilea and Haifa will be showered by rockets from South Lebanon like we have seen in 2006.
I see no reason for the airport to be closed completely. Many flights will be cancelled for sure.
Mycara, you might want to go to Israel sooner than later! Seriously, I don't think anyone of us knows what will happen. But if things do start up, I agree, all bets are off. It is a good bet that Hizbollah will launch missles, as might Hamas. Time will tell, I guess. We'll know soon enough - it's already February.
I heard a report on Israel TV a few days ago saying that things are so boring here now that a lot of foreign correspondents have packed up and gone to more "exciting" places!
And I agree with a1. Bristolnewbie, looks like you're a big fan of Hizbollah. When I think of what Muginyah did to Buckley and others, and his history of violence - I could not in good conscience support such an organization. Just one man's humble opinion.
Mycara, you're not going to Europe, you're going to the Middle-East. No one can predict whether or when Israel will attack Iran, and what will be the scale of retaliations.
The Israeli Governement has been speaking of attacking Iran for years so chances are it will never happen or not before a long time, but there are no guarantees.
I suggest you travel to Israel / Palestinian territory as planned, there's no reason to worry. Make sure you have a cancellation policy. Should anything happen, the US embassy will evacuate you so keep their number while travelling.