Swimmers have been warned not to go into the sea at a beach over pollution fears.
Thousands gathered at beaches across the UK yesterday, which was the hottest day of the year as temperatures reached the late 20s for most parts.
But the Environment Agency has warned people flocking to Withernsea beach in Yorkshire not to swim in the water despite the heat.
It's because of pollution "from dredging or construction work" and was first recorded on June 15, HullLive reports.
They said the problem was expected to last until September 26, meaning beachgoers will be advised against swimming in the water there throughout the summer months.
On its website, the Environment Agency said: "This incident has been identified as an abnormal situation, water quality monitoring has been suspended. Monitoring will resume once the incident is over."
It comes as Brits prepare for another sizzling day as temperatures look set to reach 34C.
The mercury hit 32.6C at Heathrow yesterday, beating the previous record of 28.9C set at the end of May.
But that record could be beaten again today as Thursday is set to be even hotter than Corfu.
Sunseekers flocked to beaches and beauty spots yesterday and the same trend is expected today as Brits plan day trips to enjoy the sunshine.
Met Officer forecaster Alex Burkill told Mirror Online: "In the London area temperatures will probably be similar to yesterday, when it was 32.6C.
"They will probably be around 32C or 33C today.
"However, further West, particularly around Bristol and in Wales, we will probably get highs of 33C or 34C."
A heat-health alert, level two, has been issued for all of England as health officials advised the most vulnerable to protect themselves amid the "exceptionally hot weather forecast this week".
The Met Office raised the level of its heat-health alert to three for the West Midlands and East Midlands on Wednesday.
Mr Burkill said Friday will be another hot day, but less hot than today in many places.
The forecaster confirmed today will be the hottest day of the year so far.
However, he warned heavy thunderstorms will develop particularly tonight and tomorrow.
The Met Office has two thunderstorm warnings out which cover pretty much all of the UK because of a risk of torrential downpours - with hail, frequent lightning and heavy rain expected.
Mr Burkill said: "This marks the transition to something more changeable as we go into the weekend.
"We are going to see spells of rain, stronger winds and temperatures are going to be less hot."
The forecaster said some places will see temperatures dropping by 10C - remaining mainly in the low-20s.
The highest UK maximum temperature recorded in June is currently 35.6C, set at Mayflower Park, Southampton on June 28, 1976.
