Millions of hay fever sufferers are to ensure further days of misery as pollen levels continue to be at the highest they've been all year.
Soaring temperatures - which topped 31C yesterday in Ballywatticock, County Down - are triggering the huge pollen surge.
Speaking to Mirror Online, Ben Stroud, meteorologist at Met Office, said: "We are pretty much at the peak of pollen levels at this moment in time. It's the height of the grass pollen season but we are seeing weed pollen prevalent too.
"We are likely to see pollen levels remain so high through the week until they subside next weekend, in line with a change in the weather.
"Pollen levels are high across the board, across the country, with the exception of the north of Scotland."
The expert said the balmy weather has helped plants across the UK develop pollen and this weather is expected to continue for some days yet.
He added: "Sufferers should try to stay out of the sunshine in the peak of the day.
"As difficult as it is, it is best to try to stay indoors."
Allergy experts have echoed forecasters' warnings.
"Hay fever sufferers will bear the brunt of the highest pollen counts of the year," airborne allergens expert Max Wiseberg said.
"Although a lot of people have complained about a terrible year for hay fever, the pollen counts so far have infrequently been high across the UK.
"But in the coming days we'll see very high pollen counts across England and high in most other regions of the UK, which hasn't happened yet this year."
Warm air has moved northeast across the UK from the tropical Azores islands. It's caused the mercury to rise rapidly and Brits were finally able to enjoy parks, beaches and tourist attractions yesterday.
Met Office, though, says pollen levels are high today for each region of the UK, except Orkney and Shetland, Grampian and Highlands and Eilean Star. They remain high all week, particularly bad in Wales and southwest England.
Grass pollen levels are at their highest, but it is weed pollen season currently too. The tree pollen season typically ends in June but sufferers have reported symptoms this month.
Mr Wiseberg added: "This pollen explosion will be happening because we've had hot weather followed by a lot of rain, repeatedly this year.
"This is perfect for creating the most amount of pollen possible."
After a clear night, especially in the south, Brits will continue to bask in glorious sunshine on Monday.
But it is reported the heatwave will come to an abrupt end on or around Friday.
Tom Morgan, meteorologist at the Met Office, said: "We have got quite an extended hot spell of weather to come through the next several days lasting much of this week, nighttime temperatures will be in the high teens Celsius and daytime temperatures will be in the high twenties or low thirties.
"It's going to mean that people are really going to feel the effects of the heat as we go through this week."
