This week’s high temperatures will be bolstered by blasts of heat near the Continent
With thermometers poised to rise close to 80F the Government has issued another raft of pollution alerts.
Parts of the UK including Devon, Cornwall, London and the southeast will see levels creep up from tomorrow (Tuesday) towards a ‘high’ by the end of the week.
Once again people with breathing and heart problems have been warned to avoid outdoor activities and carry medication.
It comes as Britain prepares to bake in another early-summer heatwave with the mercury expected to rocket into the 70s.
Tomorrow (Tuesday) is tipped to be the hottest day of the year so far beating the 21.9C (71F) recorded in London at the end of last week. Then Wednesday is predicted to get even warmer.
The warm weather is partly thanks again to high pressure dragging hot air in from France and Spain.
However it will be loaded small particles and chemicals thrown into the air from motor vehicles and fires.
The Department for Environment Food and Rural Affairs (DEFRA) warned Thursday and Friday will see the highest levels.
A spokesman said: “Light winds may allow high air pollution levels to accumulate across southeast England.
“Friday – further areas of high air pollution are possible, this time across southwest England as air from the Continent arrives.”
Chris Burton forecaster for The Weather Network, said the mercury will hit 77F (25C) by the day after tomorrow (Wednesday).
However he warned heavy downpours in the north and Scotland is likely to dump up to two inches of rain over the next two days.
He said: “25C is possible in a few places across southern England during Wednesday afternoon.”
It won’t be warm and sunny everywhere however, with Scotland, Northern Ireland and northern England plagued with more cloud and outbreaks of rain through Tuesday and Wednesday.
“Some of the rain will be heavy, particularly across western Scotland where more than two inches (50mm) could fall over the next 48hrs.
“Pollution levels are expected to remain fairly low through Tuesday and Wednesday but as we go into Thursday and Friday, southern England could see elevated pollution levels as easterly winds drag heavily polluted air off the near Continent.
“Current forecast suggest pollution will be in the Moderate category through Thursday and Friday in southern England and south Wales with local pockets of High pollution.”
The Met Office said pollen levels are also set to hit ‘moderate’ this week meaning a double-whammy of misery for allergy sufferers.
Hay fever treatments have been flying off the shelves over the past week with the often cool and wet March blamed for a surge in symptoms.
Allergy expert Max Wiseberg of HayMax balms, said: “We have seen a large increase in sales compared to this time last year.
“There is definitely a rise in the number of people with symptoms, and consequently people buying treatments this early on.
“This is partly due to March being cool and then immediately warm soon afterwards causing birch trees to release high levels of pollen.”
Experts say air pollution, especially in London, kills around 4,000 people in the capital and almost 30,000 nationwide each year.
Allergy UK warned high levels of allergens and pollutants can trigger potentially fatal asthma attacks.
Clinical director Maureen Jenkins said: “Hay fever can bring on symptoms in people who suffer from asthma and this is made worse when pollution is high.
“Pollen and particles in the air cling together and have a joint effect, high pollution levels can certainly be a problem, especially in people with existing conditions.”
After today’s (Monday) brief lull in the fine weather Britain is about to enjoy another dose of early summer sunshine an blue skies.
Some long-range outlooks suggest the good weather could be here to stay right through until the end of June.
The Met Office is predicting temperatures of up to 77F (25C) in the south this week with highs of 16C (61F) elsewhere.
Under clear skies and sunshine it will feel close to 80F (27C) in the south – more than double the 11C average for the time of year.
This week’s high temperatures will be bolstered by blast of heat from the near Continent where pollution levels are forecast to hit ‘very high’.
The south will enjoy the best of the weather this week although the UV index, which indicates the sun’s strength, will push ‘5’ in sparking warnings to use suncream.
Temperatures double the average maximum (11C) this early in the month mean Britain could yet see the hottest April day in almost 70 years.
With more than a fortnight until the end of the month the mercury could top the 29.4C (84.94F) recorded in Camden, London, on April 16, 1949.
Defra said pollution levels will start to creep up tomorrow (Tuesday) with ‘low’ to ‘moderate’ levels forecast in central and eastern regions before hitting ‘high’ in the south on Thursday and Friday.
Met Office forecaster Dan Williams said: “Tuesday is likely to be the hottest day of the year so far and then Wednesday may top that again.
“We have a warm tropical maritime coming air mass coming in from the Azores with temperatures of 25C likely by mid week.
“There is also some warm air coming in from northern France.”