The warning is set to come into force at 1pm on Wednesday, June 8, and is set to last until 8pm as forecasters state that “thunderstorms are likely to develop during Wednesday afternoon”.
The Met Office said: “Rain gradually clearing during the morning to give a brighter afternoon with sunny spells and occasional showers, these heavy and slow-moving in places with a chance of thunder and hail.
"Showers gradually dying away into the evening to leave a drier night for many with some clear spells.”
Despite the wet weather being forecast, temperatures are set to hit daily highs of 18°C meaning that it could feel quite humid in some parts of the region.
Forecasters have warned that the yellow weather warning means 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.
Should flooding or lightning strikes occur, then there is a chance of delays and some cancellations to public transport services such as trains and buses.
Road conditions could also be affected due to spray and sudden flooding, resulting in difficult driving conditions and some road closures.
The Met Office also says that there is a slight chance that power cuts could occur in some areas affecting both homes and businesses.