Heavy rain will move in through Wednesday afternoon and evening, becoming persistent in places during the evening. 20 to 30 mm may fall within 3-4 hours in a few locations.

Rain may also turn to snow over the higher routes in south Wales towards midnight, perhaps with a few cm accumulating.

What to expect

Spray and flooding on roads probably making journey times longer
Bus and train services may be affected with journey times taking longer
Flooding of a few homes and businesses is possible

Regions and local authorities affected

Blaenau Gwent
Bridgend
Caerphilly
Cardiff
Carmarthenshire
Ceredigion
Merthyr Tydfil
Monmouthshire
Neath Port Talbot
Newport
Pembrokeshire
Powys
Rhondda Cynon Taf
Swansea
Torfaen
Vale of Glamorgan