HEAVY showers and thunderstorms have been forecast by the Met Office as it issues a yellow weather warning for tomorrow, Saturday, June 7.

Frequent heavy showers and thunderstorms are expected for much of Saturday before fading from the west during the mid to late afternoon, the Exeter-based forecaster has said.

The warning comes into force at 9am and lasts until 6pm.

Between 10 and 15 millimetres of rain could fall in less than an hour, while some places could see between 30 and 40 millimetres of rain over several hours from successive showers and thunderstorms.

Frequent lightning, hail and strong, gusty winds will be additional hazards.

There is a good chance driving conditions will be affected by spray, standing water and/or hail, leading to longer journey times by car and bus.

And there will probably some damage to a few buildings and structures from lightning strikes, with some short term loss of power.