Metropolitan Line: No service between Chalfont & Latimer and Chesham due to a signal failure at Chalfont & Latimer, this service is not expected to resume until after lunch time today. SEVERE DELAYS between Baker Street and Watford, and MINOR DELAYS between Harrow-on-the-Hill and Amersham due to a signal failure at West Hampstead. Tickets are being accepted on London Buses. GOOD SERVICE on the rest of the line.