Don't they have sirens for this sort of thing?

So apparently yesterday we were briefly under a tsunami watch.

Of course we didn't find out until it was over, and no tsunami actually struck. Come to think of it, Nelson was out surfing during said "watch", but that is not the point. We live in New Zealand, a highly developed nation, not some tiny island of 50 inhabitants. We are advised of every rugby league and cricket score from around the world and often given play by play accounts. Shouldn't they have some way of letting us coast-dwellers know that a ginormous wave could come smashing down on us at any moment?

Granted the quake that could have spawned the psuedo-tsunami (not often that you can use 2 non-phonetic "s" sounds in the same sentence) happened in Tonga, which is 1,000 km away. And granted the tsunami warning was only 1 hour long. But still... I would like to know.

Luckily we live at the top of a large cliff. I think we'd be ok.