A spring tide boosted because the Moon is near perigee, its closest point in its elliptical orbit, at the same time as new or full moon. The stronger tidal force raises high waters and lowers low waters beyond a normal spring, usually by several centimetres to a few tens of centimetres, enough to cause flooding where water already runs close to thresholds. They come in clusters a few times a year and are the tides the public calls king tides.
Perigean spring tide Saturday plus an onshore wind, so expect the low parts of Front Street to go under.
Also heard as
- perigean tide
Related terms
Spring tide
A tide of larger than average range, occurring around new and full moon when Sun and Moon pull in line.
King tide
Informal name for the highest tides of the year, usually perigean spring tides.
High tide flooding
Shallow coastal flooding that happens when ordinary high tides exceed a local flood threshold, often without a storm.
Tide-generating force
The small difference between the Moon's or Sun's pull at a point on Earth and its pull at Earth's centre.