For a heatwave in the county, the 26C heatwave threshold must be passed for three consecutive days which is set to be the case. It comes as the Met Office is warning that a widespread heatwave is likely to develop across large parts of England and Wales as high pressure builds through the week. Met Office deputy chief forecaster Mike Silverstone said temperatures are expected to steadily increase through the weekend and into next week. He said: "A fairly widespread heatwave is likely across large parts of England and Wales, with hot conditions developing in places." The Met Office says July was the driest on record for England and Wales, while the Environment Agency has reported falling reservoir levels across the country.