THE MET Office has issued two weather warnings for thunderstorms covering the majority of Friday, September 20 and Saturday, September 21.

The yellow warning, which warns people to be prepared and is the lowest level of the coloured warnings issued, will be in place between 12pm and 9pm on the Friday and then from 1am until 11.59pm on Saturday.

A Met Office spokesperson said: “A few thundery showers may be present across southern and southeast England early on Friday, but from the middle of the day they are expected to develop more widely within the warning area. Whilst some places will remain dry, where thundery showers do occur, they will bring frequent lightning, gusty winds, potentially some large hail, as well as brief spells of heavy rain. 15-25 mm of rain fall may fall within an hour, with a very small chance of 30-40 mm falling in three hours; the latter most likely across southwest England. Showers will tend to ease and fade during Friday evening.

Regarding Saturday, they added:“Whilst there is some uncertainty in the details , scattered showers and thunderstorms are likely to develop and spread northwestwards at times later on Friday night and through Saturday. While much of the time it will be dry, and not all places will see these, where they do occur 20-40 mm could fall in less than an hour, with a small chance of isolated accumulations of 50-70 mm over the course of a few hours. In addition, hail and frequent lightning may accompany the most intense storms, especially during Saturday afternoon and evening in parts of the Midlands, southern England and east Wales.”

A forecaster for independent service Kernow Weather Team observed of the thunderstorm potential: “While most of Cornwall will, remain dry, during late afternoon, showers will gradually move towards Cornwall from an easterly direction. Where thundery showers do occur, they will bring frequent lightning, gusty winds, potentially some large hail, as well as brief spells of heavy rain. This could lead to some locations seeing plenty of standing water on our road networks. Showers will tend to ease and fade during Friday evening.

“As mentioned above thunderstorm could start outside of the yellow weather warning zone, due to the complexity of the set up for this weather event.”