If you’re at the beach on Sunday, don’t be alarmed if you hear an unusual siren. At noon on April 6, Auckland Civil Defence will run the first of its twice-yearly tsunami siren checks on the north and west Auckland coasts to coincide with daylight saving ending. The test sequence will be three sets of tones, each signalling a specific action. They will sound for one minute each and there will be 15 seconds between each set. In an emergency, tones will sound for longer.