Tailbacks clear after M4 Brynglas tunnels floods
Tailbacks on the M4 in Newport, after one lane in each of the Brynglas tunnels was blocked due to flooding, have now cleared.
Strong winds also closed one lane of the M48 Severn Bridge in both directions, but they have reopened.
Dyfed-Powys Police has reported a number of flooded roads in Powys, Pembrokeshire and Carmarthenshire.
A yellow 'be aware' weather warning was re-introduced in parts of Wales on Sunday.
The Met Office warned of heavy rain in the morning, followed by heavy showers, from 04:00 GMT. This latest band of heavy rain is expected to last until Tuesday.
The chief forecaster said a greater risk of localised flooding than normal might be expected given the already saturated ground following weeks of heavy rain.
Dyfed-Powys Police tweeted there was flooding on the A40 both between Corner Piece Inn and Puncheston, Pembrokeshire, and near Talybont-on-Usk, Powys.
The force also said there was flooding on the A479 at Cwmdu and the A4138 at Talyclun, both Carmarthenshire, and just off junction 48 of the M4 at Pontarddulais.
Officers in the area also warned of flooding on many smaller roads, as well as surface water.
Mid and West Wales Fire and Rescue Service said they were inundated with calls about flooding, both in houses and on roads.
The service tweeted about crews attending flooding incidents in Neath, Margam, Swansea, Llanelli and Pembroke.
South Wales fire service said it had been called out to flooding in Newport, Cwmbran and Abergavenny.
Natural Resources Wales has multiple flood alerts in place.
The weather warning covers Blaenau Gwent, Bridgend, Caerphilly, Cardiff, Carmarthenshire, Merthyr Tydfil, Monmouthshire, Neath Port Talbot, Newport, Pembrokeshire, Powys, Rhondda Cynon Taff, Swansea, Torfaen and Vale of Glamorgan.