The Met Office has issued a yellow weather warning for thunderstorms, threatening a number of Platinum Jubilee celebrations set to take place across the country.
Wales is braced for thunderstorms until around 6pm today (Friday), while the weather warning also covers south west England from midnight tonight through to Saturday morning.
While many places will stay dry as the Queen's Jubilee celebrations continue, thunderstorms will bring heavy rain and lightning to some places early on Saturday.
There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds. Power cuts could also occur at some homes.
Over the course of the bumper bank holiday weekend, some 16,000 street parties are due to take place up and down the country, with local councils saying they received "a huge number of applications" from residents wanting to celebrate the Queen's 70 years on the throne.
On Saturday evening, a platinum party will be held at Buckingham Palace. The huge event will include live music from the likes of Queen, Hans Zimmer, Alicia Keys and Craig David.
It kicks off at 8pm and is expected to last between two to three hours and will be broadcast live by the BBC. 22,00 tickets were available for the event, including 7,500 for key workers and members of the armed forces.
Those holding events on Saturday morning will be hoping the rain keeps at bay, although the Met Office's latest warning for the south west could dampen spirits.
There is also the possibility of thunderstorms moving north into southern counties of England during the early hours of Saturday, although these are expected to ease come later in the morning.
Many places will miss the worst of the thunderstorms but the areas that are hit could face frequent lightning and heavy rain.
Some places could even see 20-30mm of rain fall within an hour, with a small chance of 50mm rainfall in two to three hours, most likely near the south coast, as thousands are set to enjoy street parties and celebrations.
The weather warning in the south west is in place from midnight tonight through until 10am Saturday morning.
The Queen's Platinum Jubilee celebrations got underway on Thursday with Trooping the Colour and a spectacular Red Arrows flypast over Buckingham Palace.
After Trooping the Colour, the Queen met her great-granddaughter Lilibet, who celebrates her first birthday tomorrow, for the first time, and had a private lunch with Prince Harry and Meghan Markle at Windsor.
The event was the first time that Prince George, Prince Louis and Princess Charlotte took part in a military procession together, with Louis stealing the show after clasping his hands over his ears as the roaring flypast soared overhead.
The momentous day concluded when the monarch, 96, led the lighting of thousands of platinum jubilee beacons.
The Queen pulled out of today's thanksgiving service at St Paul's Cathedral, with the monarch saying she suffered "some discomfort" during the celebrations.
It's hoped the weather will clear as Saturday progresses, with further street party lunches set for Sunday alongside the Jubilee Pageant, with a 3km carnival procession taking place down The Mall.
It will feature a performance from Ed Sheeran, the singing of the national anthem and tributes to the Queen's reign.
