Amber warning of extreme heat affecting London & South East England: Bracknell Forest, Brighton and Hove, Buckinghamshire, East Sussex, Greater London, Hampshire, Kent, Medway, Milton Keynes, Oxfordshire, Reading, Slough, Surrey, West Berkshire, West Sussex, Windsor and Maidenhead, Wokingham valid from 2300 Fri 26 Jun to 2000 Sat 27 Jun