Madge said there is a 50% chance that temperatures will reach 40ºC somewhere in the UK, probably along the A1 corridor.
“If we get to 40ºC, this is a very iconic threshold and it shows that climate change is with us now,” he said.
“This is becoming much more likely due to climate change.”
The UK Health Safety Agency has increased its heat health warning from level three to level four: a “national emergency”.
It reaches level four “when the heat wave is so severe and / or prolonged that its effects extend outside the health and social system … At this level, illness and death can occur among people fit and healthy, and not just in high-risk groups, ”he said.
“Substantial changes to daily routines”
A “substantial disruption” to travel and power supply is expected, while there may also be widespread damage to property and infrastructure, according to the Met Office website.
People will have to make “substantial changes in work practices and daily routines,” the weather agency said.
Britain will suffer “delays in roads and road closures, along with delays and cancellations of rail and air travel, with major welfare problems for those experiencing even moderate delays”.