There is a moderate risk of severe weather affecting northern and western parts of the UK on Thursday.
Heavy rain will spread to many areas of the UK during Thursday, particularly northern and western areas, where there will be rainfall totals of 15-25mm, and locally 40 to 50mm over higher ground.
Rain will be accompanied by strong to gale force southerly winds in places.
Issued at: 1259 Mon 18 Jan
Bydd y wybodaeth hon yn cael ei diweddaru wrth i'r sefyllfa ddatblygu.
Cynghorir y cyhoedd i gymryd gofal ychwanegol a ffonio Llinell Lifogydd Asiantaeth (cysylltiadau allanol) yr Amgylchedd am rybuddion o lifogydd a chyfeirio at Traffig Cymru (cysylltiadau allanol) am gyngor am gyflwr y ffyrdd.