Replacement bus services are running on some trains between Bangor and Holyhead due to flooding between Llanfairpwll and Bodorgan.
It is hoped that rail services to Holyhead will be able to resume from around noon.
Icy by night, chilly by day - brace yourself for a cold week ahead.
High pressure keeps the weather chilly by day, icy by night, with an increasing risk of freezing fog.
High pressure this weeks means mainly cold bright days and icy cold nights.