Regression of the lunar nodes | National Tidal and Sea Level Facility National Tidal and Sea Level Facility Tides Storm surges Products About About tides Tides – questions and answers Sea level – questions and answers The Doodson-Légé Tide Predicting Machine Tide clocks and watches Tidal river bores The River Dee / Afon Dyfrdwy The River Mersey UK National Tide Gauge Network Data availability Tidal predictions – UK and Ireland UK South Atlantic Network Gibraltar sea level station Tidal predictions – South Atlantic Tide gauge instruments Definitions of tidal levels Chart datum and ordnance datum Permanent Service for Mean Sea Level (PSMSL) (external link) Engineers’ page Proudman Building, Liverpool weather station About storm surges Tide-surge model Surge model forecast Surge model archive Surge model archive: 2004–2019 Surge model ensemble forecasting Skew surges Skew surge history: England – south Skew surge history: England – east Skew surge history: England – west Skew surge history: Wales Skew surge history: Scotland Skew surge history: Northern Ireland Skew surge history: Isle of Man Skew surge history: Channel Islands Sea level trends Sea level trend charts Software Regression of the lunar nodes Highest tides for 18.6 years Many places along the UK coastline will experience the highest tide for 18.6 years between 19–30 September 2015, as a result of the coincidence of a series of astronomical factors. This unusually large spring tide is due to the moon and sun becoming aligned directly over the equator at the same time as the moon’s ‘nodal cycle’ reaches a stage favourable to high tides. In this video, Prof. Kevin Horsburgh explains the ‘regression of the lunar nodes’. No video playback capabilities, please download the video below Download video closed format: MP4 127MB