Tsunami alert but no wave

Earlier today, Eric came in from collecting the mail and said, "Have you heard about the tsunami threat to the Queensland coast?" Me: "What? Is this an April Fool's joke?" (At that time it was still April 1 in Hawaii, where the warning came from.) Eric: "No, it was a genuine warning from the Pacific Tsunami Warning Center in Hawaii, because of an earthquake near the Solomon Islands, but no reports of significant sea level rises have been received, so no tsunami is now expected." We then looked it up on the web, which said "some rises of about 20-30 cm have been observed". So we kept an eye out for any sea level rises here, but we didn't notice anything (not that we expected to). A very small rise was recorded on the instruments at Sydney Harbour. According to the evening news, schools were closed on much of the east coast and lots of people headed for high ground, as a precaution, remembering the Indian Ocean tsunami. By the time we heard about it, the wave (had it existed) would have been on us. Fortunately our apartment is well up on a hill, so we'd probably not be washed away, but a true tsunami would wreck havoc on the town and the road out, and the power supply etc. At least our cyclone preparations (food, water, camping/cooking gear) would serve us well in such a situation! [Edit] In the Solomon Islands themselves, big waves (up to 10 metres?) did occur.