The Met Office warning for heavy rain has been raised to 'Amber - be prepared' for tomorrow (Saturday) .
A WARNING of flooding has been issued for much of Wales with heavy rain expected to fall overnight.
Thunderstorms could bring localised torrential downpours across the country during Saturday morning with only the extreme west and north west of Wales likely to escape the heaviest rain.
This could cause localised flooding of roads, and flooding from drains, ditches and small streams.
There is also a risk that that localised torrential downpours could cause smaller, faster responding urban rivers to rise.
Natural Resources Wales will issue Flood Alerts and Warnings if rivers reach trigger levels.
At this stage given the rainfall forecasts, Natural Resources Wales does not expect large slower responding rivers in Wales to be affected.
People travelling tomorrow are advised to take extra care and allow extra time for their journey as driving conditions may be hazardous.
Natural Resources Wales is advising people to keep an eye on weather reports and local news for details of any disruption in their area.
Organisers of outdoor events are also advised to check the Met Office website for the most up-to-date forecasts.