The weather warning says: “On top of the widespread 20-30 mm of rain, and with some places seeing as much as 40mm of rain, a further 20-30mm, and very isolated totals of 50-60mm, are expected through Monday and Tuesday, before rain and showers finally begin to ease.”
The warning has been extended until Tuesday evening.
The Met Office said: “Spray and flooding will likely lead to difficult driving conditions and possibly even some road closures.
“Bus and train services probably affected with journey times taking longer.
“Flooding of a few properties is possible.”
Follow live updates on the weather to keep up to date with disruption and potential flooding here: Storm Herminia brings strong winds to South Wales | South Wales Argus
Here is the hour-by-hour chance of rain:
1pm: 50%
2pm: 60%
3pm: 60%
4pm: 40%
5pm: 40%
6pm: 60%
7pm: 70%
8pm: 80%
9pm: 90%
10pm: 80%
11pm: 70%
