The lunar month’s highest tide occurred between 5th and 6th July 2020 for Waitemata habour and Great Barrier Island.
The Waitemata harbour tidal gauge measured a mean level of 1.72 metres between 7:00pm and 7.15pm on 5th July which is right on average for the 2015 to 2019 July period. The air pressure at the time of the reading was 1006.1 hPa, so when using the inverted barometric adjustment calculation method of 1cm for every 1 hPa, the projected height would have been 1.65 metres at the mean sea level pressure of 1013 hPa. More on meteorological effects on tides can be found here.
The ongoing trend between 2014 to 2020 for the Waitemata harbour sea level peak is a slight downward trend. The tidal gauge data used for this analysis can be found here.
The Great Barrier Island tidal gauge measured a mean level of 1.17 metres between 8:00pm and 8.15pm on 6th July. The air pressure at the time of the reading was 1005.81 hPa, so when using the inverted barometric adjustment calculation method of 1cm for every 1 hPa, the projected height would have been 1.10 metres at the mean sea level pressure of 1013 hPa. More on meteorological effects on tides can be found here.
The ongoing trend between 2014 to 2020 for Great Barrier Island sea level peak is a slight upward trend. The tidal gauge data used for this analysis can be found here.
