LONDON Heathrow Airport has told airlines to cancel one in five flights during a two-hour period later on Saturday afternoon, as Britain faces further heavy storms and lightning that have hit many parts of the country in the last 24 hours.
Britain's Met Office said on Saturday that heavy, thundery showers will move across England and Wales, with amber warnings in place across much of the country.
Torrential downpours, frequent lightning, large hailstones and strong winds are expected where thunderstorms form.
A spokeswoman for Heathrow, the world's third busiest airport, said that one in five flights will be canceled between 4 p.m. and 6 p.m. (11.00 a.m. EDT to 1.00 p.m. EDT), when there is a strong likelihood of poor weather conditions.
"There is severe weather forecast at Heathrow for Saturday 19 July with a 70 percent risk of thunderstorms, lightning strikes and hail storms," she said.
Among the roughly 20 expected cancellations are flights from destinations including Madrid, Dublin and Prague, according to the airport's website, with delays on a small number of other routes so far.
There are currently over 50 flood alerts in place across the country.