The phenomenon, which scientists call a 'perigee moon,' occurs when the moon is near the horizon and appears larger and brighter than other full moons.
When the moon reaches its closest approach to earth at around 6pm it would be just 221,765 miles away and would appear 16 per cent larger and 30 per cent brighter than usual. Astronomers are expected to be lapping up the event which would see the moon travel 863 miles closer to the earth than normal.
Supermoons have been proven to cause sea levels to rise as the gravitational pull of the Earth's closest neighbour increases as it gets closer. Such events have been linked to earthquakes, volcanic eruptions and devastating tidal waves including the Boxing Day tsunami of 2004.
This super moon would also coincide with the arrival of Storm Bertha currently hurtling across the Atlantic and due to rip into Britain on Aug 10.