TEMPERATURES have been set to hit 28C as Brits welcome a slightly cooler day than yesterday's scorching 38C.
Brits suffered overnight as they battled roasting conditions, but woke up this morning to showers. But what lies ahead for the rest of today? We take a look at the latest forecast.
How hot will it be today and will it rain?
The hot weather is blasting in from an African plume of Saharan air, but showers today across Wales and southern England could see a much cooler-feeling day, despite temperatures in the high twenties.
There won't be much sunshine across the UK today, with lots of grey cloud everywhere but the Western Isles of Scotland.
Thunderstorms are expected in central and east England, but temperatures will remain hot.
Overnight, heavy rain is set to continue and unfortunately, in Northern, Eastern and central England humidity will be high.
Yesterday was the second-hottest day ever, reaching 38C in parts of England.
The high heats sparked travel disruption accross the country with many trains in particular cancelled or delayed.
Public Health England has issued a warning advising vulnerable people, especially older people and young children, to stay hydrated and stay indoors to keep cool.
Medical experts are warning that few hospitals are prepared for the impact of the intense heat.
People are being urged to take precautions against the heat by avoiding exercise and wearing loose, light clothing.
Experts at the Met Office say there is "no doubt" climate change is playing a role in the unprecedented temperature highs.
What is the summer forecast?
has predicted a warmer than average summer in most of the UK
It adds: "The driest and warmest periods are expected to be in August.
"Over the three-month period the forecast is for central England temperature to be 0.5C to 1.5C above the average.
"Precipitation levels of between 95 per cent and 115 per cent are suggested."
What is a heatwave?
The World Meteorological Organisation definition of a heatwave is "when the daily maximum temperature of more than five consecutive days exceeds the average maximum temperature by 5C, the normal period being 1961-1990".
They are most common in summer when high pressure develops across an area.
High-pressure systems are slow-moving and can persist over an area for a prolonged period of time such as days or weeks.
They can occur in the UK due to the location of the jet stream, which is usually to the north of the UK in the summer.
This can allow high pressure to develop over the UK resulting in persistent dry and settled weather.
When was the hottest heatwave in UK history?
The scorching summer of 1976 was the hottest summer since records began.
It led to a severe drought owing to the exceptionally dry conditions, although it is thought that 1995 was drier.
In the summer of 1976, Heathrow had 16 consecutive days over 30C from June 23 to July 8, and for 15 consecutive days from June 23 to July 7 temperatures reached 32.2C somewhere in England.
But the single hottest temperature of 38.5C was set on August 10, 2003.
What should you do during a heatwave?
When the mercury shoots up there are several obvious precautions to take.
It is advised to make sure you drink a lot of water to make sure you stay hydrated during the hot spell.
Keeping feet cool and running cold water on your wrists can also help.
Keeping a bottle of sunscreen with you to soak up those UV rays is also highly advisable as is ensuring you have a hat to prevent sunstroke.
If you are working in an office, ask whether there is air conditioning that can be used.
If you're travelling by public transport, try and travel at hours which will be less crowded, so the risk of overheating is less likely.
There are no maximum temperatures in place for work and school environments but employers and education facilities have to provide "clean, fresh air".
The National Union of Teachers said special measures should be put in place to reduce temperatures as soon as staff complain about feeling uncomfortable.
Special measures can include electric fans and relaxing uniform restrictions.
Parents should also make sure their kids are well equipped in a heatwave, with a hat and sunscreen if they are likely to be playing outdoors.
Using electric fans - including hand-held ones - can help move the air and cool a person down.