The latest monitoring report, which brings together the most recent data on traffic speeds, journey times and air quality, was published by Transport for Wales (TfW) in September 2024.
Cafodd yr adroddiad monitro diweddaraf, sy’n cynnwys y data diweddaraf am gyflymder traffig, amseroedd teithiau ac ansawdd aer, ei gyhoeddi gan Trafnidiaeth Cymru ym mis Medi 2024.