Storm-Tide Red-Alert Days 2011
Science Centres: Coasts, Natural Hazards
The “red-alert” dates are proposed as days that Emergency Managers and Coastal Hazard Managers should write in their diaries and keep an eye on weather, river and sea conditions (low barometric pressure, winds, rainfall and waves).
Dates averaged across New Zealand – check tide forecasts for specific locations.
| Red-alert Dates (highest high tides) | Carefree Dates (lowest high tides) |
|---|---|
| [actual perigee] | [actual apogee] |
| 21-24 January [22 Jan] | 13–15 January [10 Jan] |
| 18-23 February [19 Feb] | 11–13 February [7 Feb] |
| 19-24 March [20 Mar] | 13–14 March [6 Mar] |
| 17-22 April [17 Apr] | |
| 16–20 May [15 May] | |
| 24-26 July (22 July) | |
| 1–3 August [3 Aug] | 21-24 August (19 August) |
| 29 August–3 September [31 Aug] | |
| 27 September –3 October [28 Sep] | 20–22 September [15 Sept] |
| 26 October - 1 November [27 Oct] | |
| 25–29 November [24 Nov] | |
| 25–28 December [22 Dec] |
In 2011 the Moon's closest perigee occurs on 20 March and coincides with a Full Moon.
For the year 2011, "red-alert" dates cluster around very high tides (perigean-spring tides) that peak 1-2 days after New or Full Moon, when the Moon is in its perigee and "carefree" dates cluster around lower high tides after the first or Third Quarter when the Moon is close to its apogee.
The “red-alert” dates are proposed as days that Emergency Managers and Coastal Hazard Managers should write in their diaries and keep an eye on weather, river and sea conditions (low barometric pressure, winds, rainfall and waves).
For further information see Red-alert days for coastal flooding.