YELLOW weather warnings could put a damper on any weekend Jubilee celebrations.

On Saturday morning, thunderstorms should miss Gwent but are expected in the Severn Estuary.

But a second weather warning on Sunday could spell 18 hours of rain in South East Wales.

READ MORE: Hour-by-hour Jubilee weekend weather forecast for Newport and Gwent

"Thunderstorms developing over parts of England and Wales from early Sunday may cause travel disruption and, in a few places, flooding," the Met Office said of the yellow warning that will last from midnight tonight until 6pm on Sunday.

And this evening could bring further bad weather over a certain Buckingham Palace, where the Platinum Jubilee celebrations are expected to draw a crowd of more than 20,000 people.

Forecasters are predicting the second bout of storms will arrive after the Jubilee event in London, which will feature performances from the likes of Craig David, Alicia Keys, and Sir Rod Stewart.

Met Office meteorologist Steven Keates said: “It will be late evening so I think for events in London I wouldn’t want to completely discount a shower for, say, the Party at the Palace. I think at the moment it looks like a mostly dry picture and quite pleasant conditions.”

It comes after Friday brought sudden, heavy downpours to northern parts of Wales, with the seaside town of Criccieth receiving 92mm of rain in just six hours.

Homes and businesses were left damaged and some roads impassable while many were celebrating the Platinum Jubilee.

Mr Keates said the overall picture for the UK showed “big contrasts” as Scotland recorded its warmest day of the year on Friday at 21.6C.