Sky gazers are watching weather forecasts closely in the hope of being able to see a rare blue supermoon for the first time in more than a decade.

A blue supermoon is the unusual combination of a supermoon - which appears bigger and brighter in the sky thanks to its close proximity to Earth - and a blue moon, the name given to the second full moon to take place in one calendar month.

A blue moon, which has nothing to do with the colour the moon will actually appear despite the name, happens around every two to three years, while there are around three supermoons every year.

However it is rare for the two events to come together in a year and co-incide, meaning that many budding astronomers view this week's occasion as rare and one not to be missed.

The last blue supermoon was in 2009.

How to see August’s blue supermoon?

The Royal Observatory Greenwich says this month’s blue supermoon will peak at 2.35am on the morning of Thursday, August 31.

It is the second full Moon of the month thanks to the Sturgeon Moon which appeared overhead on August 1.

Timings mean that with good weather conditions the best possible time to see the blue supermoon will be late on Wednesday evening into the early hours of Thursday.

As with all events in the night sky – a dry evening and less cloud overhead will also give those who are keen to see it - or even capture a photograph - the best chance of a good view.