NIWA has a range of online tools and information relating to tides, including a tide forecaster, yearly tide envelopes and storm tide "red alert" days.
Use this utility to forecast high and low tides anywhere in open coastal and ocean waters around New Zealand for up to 28 days. It also predicts historical tides back to 1830. This current version does not cover tides inside harbours and estuaries.
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). Includes dates for 2022 and links to previous years.