Large parts of the UK were under yellow weather warnings as a “plume of thunderstorms” moved into the country from across the English Channel.
Forecasters have predicted parts of England could see flooding and power cuts over the next few days amid the bad weather, which has seen weather warnings put in place for southeast and central England throughout most of Thursday.
A Met Office spokesperson said parts of East Anglia, the Midlands and the South East could be drenched with up to 50mm of rain in just two hours on Thursday, and up to 70mm on Friday.
“The storms will most likely be coming in on Thursday afternoon and lasting into the evening,” they said.
It came after forecasters said there was a possibility that Wednesday would be the hottest day of the year but the sun did not deliver.
What are the risks from incoming thunderstorms?
The Met Office Yellow weather warning says “there is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail and strong winds.”
Alex Burkill, from the Met Office, tells The Independent that rainfall is a concern in the incoming thunderstorms due to the rate, rather than total amount.
“Lots of people are going to see heavy storms,” he said, “the total rainfall is not expected to be high, the risk of flooding is all due to the rate of rainfall.
“Because of how intense the downpours will be, with 30mm in one hour expected, we could see localised flash flooding.”
Why is hail forecast at 30C?
Among the extreme weather events being warned of on what still could end up the hottest day of the year is hail, frozen balls of ice that seem to only fall around the time of year we can see our breath.
But, Alex Burkill from the Met Office tells The Independent, hail is not unheard of in summer. In fact, it’s usually bigger.
“During summer is when we are most likely to see large hail,” Mr Burkill explains.
“This isn’t the beach ball size hailstones we see in the US, but in the UK they can get to the size of golf balls.”
Mr Burkill said hail grows larger in summer because there is more energy in the clouds when there is more heat.
The small balls of ice form in clouds and merge together as they drop. Due to updrafts of wind, the merged hailstones go back up into the clouds, allowing them to drop and merge again.
In summer, when updrafts are more powerful, this process repeats more times, allowing for the stones to reach a larger size.
Thunderstorms crossing the channel
The Met Office has posted an update showing the thunderstorms approaching. As of 5PM we can see that the violent weather is making its way across the English channel.
Across northern France, 28 areas were placed on “orange alert”, the second highest threat level.
Brace yourself - weather warnings take effect
Yellow weather warnings covering much of the UK are now in effect as forecasters expect thunderstorms to arrive soon.
The below map shows the areas covered by weather warnings. Vertical lines indicate where the Met Office told The Independent conditions will be harshest. Please note that the differentiation seen here is ours, Met Office maintains a blanket yellow warning across the board.
Temperatures will remain high despite thunderstorms
The Met Office forecasts that temperatures will remain high overnight despite the heavy rain.
London and the southeast (set to bear the brunt of the storms) will see highs of 21C overnight, putting to rest hopes of an easy night’s sleep. Elswhere in England, temperatures are set to remain in the high teens overnight, with some parts staying above 20C.
Those celebrating in Cardiff after Wales’s win over Turkey in the Euros could see temperatures remain in the high teens well into the night. Scotland will be cooler, mostly in the low teens overnight with some areas dropping below 10C.
The dip in temperature is unlikely to put an end to the incoming thunderstorms though. Alex Burkill from the Met Office explains: “Though it will get cooler, the thunderstorm risk doesn’t disappear because there is still enough heat and energy in the atmosphere to maintain the storms.”
We want your weather pics
Lightning makes for incredible photographs and we want to see and share as many of these as we can.
So we are asking readers to share their photographs (and video) from the coming storms with The Independent on Twitter. Please! We will make sure to credit any of the posts we use.
Just tag: @Independent
Reports coming in of rain around the south of England now. Anecdotally, I can tell you that it is raining in London. Not extremely heavy, but very big drops.
Lightning nears UK
Lightning strikes should be visible off the Sussex coast at the moment. (Remember we asked for your pics!)
Though it is now raining across much of southern England, the lightning has not yet reached these shores.
LightningMaps.org shows where strikes are recorded live. If you are scared of thunder and lightning, you should avoid heading to their site and looking at the west coast of France and northeast Spain.
A lightning strike has now hit England. The strike was recorded at Arlington Reservoir in Berwick, East Sussex.
Many more expected throughout the night.
Here’s the Met Office’s latest forecast across the UK for early on Thursday morning:
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