WITH the mercury set to reach 30C on Thursday across much of Wales, the Met Office has today issued a yellow weather warning for thunder storms.

Thursday looks set to be the hottest day of the year so far with the temperature in Aberystwyth set to hit 32C, 30C in Porthmadog and 29C in Lampeter, but forecasters are warning that the hot air could lead to localised thunder storms later in the afternoon and through Friday.

A yellow warning is in place for all of West Wales from 4pm on Thursday through until Friday.

The Met Office says storms may develop across parts of western UK late on Thursday afternoon and into the evening.

They do say though that many places will miss the worst of the storms, but where they do occur, torrential downpours could bring up to 40mm of rain in less than two hours.

Lightning and hail are also possible.