The Met Office has declared that Gogerddan, Wales, has reached 35.3°C (95.5°F), the hottest temperature ever recorded in the country. Meanwhile, the London Broil continues:
Met Office Chief Meteorologist Neil Armstrong, said “The extreme temperatures that we have been forecasting are now beginning to build and it is likely that today we will see values reach into the high 30s, possibly challenging the UK record of 38.7°C set in July 2019.
“Even higher maximum temperatures will develop tomorrow with a 70% chance of somewhere in England exceeding 40°C. A value of this level would exceed the current UK record by 1.3°C or more. This is akin to a marathon runner shaving 20 minutes off of the current record.
“Nights are also likely to be exceptionally warm, especially in urban areas. This is likely to lead to widespread impacts on people and infrastructure. Therefore, it is important people plan for the heat and consider changing their routines. This level of heat can have adverse health effects.”
This is the first time we have forecast 40°C in the UK. The current record high temperature in the UK is 38.7°C, which was reached at Cambridge Botanic Garden on 25 July in 2019.
Weather forecast models are run numerous times to help us quantify the likelihood of a particular event occurring and estimate the uncertainty which is always present in weather forecasting to some degree. Some models are now producing a 70% chance of maximum temperatures in excess of 40°C in isolated parts of the UK for the start of next week. Mid, to high, 30s Celsius will be seen more widely with a 95% chance we will exceed the current record.
At this writing, Heathrow and London City both report 36.0°C (96.8°F). They still have more livable weather than the world's hot spot right now: Abadan, Iran, reports 50°C (122°F), but its 6°C dewpoint and 8% humidity make it feel like a much cooler 45.6°C (114.7°F).
I arrive around 22:15 BST Wednesday, when temperatures should be closer to 22°C (74°F), which is still a very warm summer day in London.