Environment Agency Wales is urging people to be alert as heavy rainfall may cause localised flooding across Wales.
Forecasts indicate that strong winds and persistent heavy rainfall are due to affect most Welsh counties from this evening, continuing into Friday.
On the South Wales coast, strong winds this evening and tomorrow morning may result in coastal surges, large waves and sea spray.
Four flood alerts have been issued for the Wye estuary, the Usk estuary, Swansea Bay and the coast from Aberthaw to the Severn Bridge.
As river levels rise, further flood alerts may be issued as well as some localised flood warnings.
Strong winds may also damage trees and cause debris to block drains which could lead to localised flooding.
Agency officers are currently checking flood defences and clearing blockages that may pose a flood risk.
The Agency is advising people to listen to local weather and traffic reports and updates on the radio or TV, or if able to, view the latest information on the Met Office website.
Care should also be taken as driving conditions may be hazardous, particularly on Friday morning, and people should listen to traffic reports for advice and for any disruption locally.
People are reminded that flood water can be extremely dangerous, and under no circumstances should people attempt to walk or drive through flood water or attempt to remove any blockages they may come across.
If people are concerned about a blockage in their local river they should contact the Agency’s incident hotline on 0800 80 70 60.