Storm-tide "red-alert" dates are "king-tide" days that Emergency Managers and Coastal Hazard Managers should write in their diaries and keep an eye on adverse weather (low barometric pressure, onshore winds), river levels and sea conditions (waves and swell).
Generally speaking, a drought is defined as a rainfall deficit which restricts or prevents a human activity – for example, farming or power generation.
Heavy rainfall is one of the most frequent and widespread severe weather hazards to affect New Zealand. It is defined as rainfall greater than 100 mm in 24 hours.
Due to its position in the 'Roaring Forties', a belt of strong winds in the Southern Hemisphere which generally occur between the latitudes of 40 and 49 degrees, as well as its small size, New Zealand is a windy country.
Risks from natural hazards are part of every day life for New Zealanders, whether it is from floods, storms, tsunami, landslides, severe weather or earthquakes.
Coming from the Japanese word 'harbour wave', tsunami are a series of waves – with wave lengths up to hundreds of kilometres between crests - caused by undersea seismic disturbances.
The waters around New Zealand have some of the highest waves in the world, being exposed to swell coming up from the Southern Ocean, as well as storms in the Tasman Sea and Pacific Ocean.
