The Met Office has issued two separate weather warnings for Thursday, one for heavy rain followed quickly by one for Thunderstorms.
Both are likely to lead to some localised flooding
Rain WarningValid 3am until 12pm
Heavy rain may lead to some localised disruption
What to expect
Flooding of a few homes and businesses is likely
Bus and train services probably affected with journey times taking longer
Spray and flooding on roads probably making journey times longer
Some interruption to power supplies and other services likely
An area of rain is expected to move westwards overnight giving some locally heavy rain during Thursday morning, before gradually clearing northwards.
Many places will see 5 to 10 mm during this period, with a few places perhaps seeing 30 to 40 mm in 3 to 6 hours which may lead to some localised disruption.
Thunderstorm WarningValid 11am until 11.59pm
Heavy rain over south-west UK and a few heavy and possibly thundery showers further east, may lead to disruption due to flooding.
What to expect
There is a small chance that homes and businesses could be flooded quickly, with damage to some buildings from floodwater, lightning strikes, hail or strong winds
There is a small chance of fast flowing or deep floodwater causing danger to life and there is a small chance that some communities become cut off by flooded roads
Where flooding or lightning strikes occur, there is a chance of delays and some cancellations to train and bus services
Spray and sudden flooding could lead to difficult driving conditions and some road closures
There is a slight chance that power cuts could occur and other services to some homes and businesses could be lost
Rain will be persistent and at times heavy across more southern parts of Wales, in South-west England and the West Country, where 30-60 mm could fall in a few places, dying out overnight.
Further east, a few slow moving heavy showers and thunderstorms may develop, possibly producing 20-25 mm of rain within an hour.
Lightning could be an additional hazard.
These dying out during the evening.