Storm-tide red-alert days 2015

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).

The dates below are averaged across New Zealand – please check tide forecasts for specific locations.

2015

Generally across NZ (dates for specific locations will lie within these dates)

Red-alert Dates (highest high tides)  

Carefree Dates (lowest high tides)  

[actual lunar perigee date]

[actual lunar apogee date]


14–15 January  [10 Jan]

20–27 January  [22 Jan]

 

18–25 February  [19 Feb*]

28 February  [5 Mar]

19–25 March  [20 Mar]

28–30 March  [1 Apr]

17–22 April [17 Apr]

27–29 April  [29 Apr]

17–20 May  [15 May]

26–28 May [27 May]


25–27 June [24 Jun]

4–6 July  [6 Jul]

25–26 July [21 Jul]

31 July – 6 August  [2 Aug]


29 August –5 September  [31 Aug]


26 September – 4 October [28 Sep*]


26 October – 2 November  [27 Oct]

 5–7 November [8 Nov]

25–29 November [24 Nov]

 5–7 December [6 Dec ]

25–27 December [21 Dec]

 

A visual respresentation of this calendar is available on the right hand side. There is also a printable PDF available for download:

Download red-alerts days calendar 2015 [PDF]

High perigean-spring tides, colloquially known as "king tides", peak 1–2 days after New or Full Moon when Moon is in its perigee (i.e., when it is closest to the Earth during its 27½ day elliptical circuit around the Earth) but actual dates of the highest tides vary around New Zealand.

In 2015, the Moon's closest perigee occurs on 28 September and coincides with a Full Moon, with next closest on 19 February (on a New Moon). the year's highest high tides will occur in January to March and end of August to October.

For the year 2015, "red-alert" dates cluster around very high tides (perigean-spring tides) that peak 1–2 days after New or Full Moon when Moon is in its perigee and "carefree" dates cluster around lower high tides after First or Third Quarter when the Moon is close to its apogee. 

View times for perigee, apogee and New and Full Moon [external link] in UTC (add 12 hours for NZST).