Thunderstorms are possible in Sussex and Surrey: Weather map reveals when storm is most likely to hit

According to the Met Office, ‘scattered heavy showers’ are forecast for most of the day in the South East.

The localised forecast for Wednesday, May 21 reads: “Mostly cloudy this morning with patchy rain slowly easing. Turning brighter from the north during the afternoon but some heavy showers and thunderstorms developing. A little cooler than yesterday but still feeling warm in any sunshine with light winds. Maximum temperature 20 °C.

“Showers dying out this evening leaving a mostly clear and colder night than the last. A chance for one or two fog patches to form, mainly in southern coastal counties. Minimum temperature 4 °C.”

The BBC weather forecast for Sussex adds: “Spells of rain will gradually move off to the south through this morning.

“Heavy scattered showers are then expected to develop during the afternoon, with a risk of thunder.

"Showers will ease this evening. Tonight is there expected to remain dry with predominantly clear skies and just the odd patch of cloud in places. Thicker cloud may move in close to dawn.”

According to www.netweather.tv, a storm is most likely to hit West Sussex between 7pm and 10pm with the risk percentage stated as 42 per cent.

In East Sussex, there is a 32 per cent chance until 10am and a 35 per cent chance at 6pm.

In Surrey, there is a 42 per cent chance of a storm at 2pm, 5pm and 6pm.

According to the Met Office, the weather will ‘turn slightly less settled’ this week, before the ‘real change in type’ comes at the weekend.

The outlook for Thursday to Saturday added: “Turning mostly cloudy Thursday, perhaps briefly with showery rain. Dry with sunny spells on Friday. Turning more unsettled this weekend, becoming breezy with outbreaks of light rain on Saturday.”

The bank holiday weekend will see a ‘marked change in weather type’.

Deputy chief meteorologist Mark Sidaway explained: “The high pressure that has been around for the last few weeks will slowly lose its grip on the UK this week, bringing a change to more unsettled conditions with many areas seeing rain or showers, ending the prolonged dry spell.

“The change comes this weekend, with weather systems moving in from the Atlantic, arriving from the west probably later on Friday and through Saturday. They will bring with them spells of rain, which may be heavy at times, with a risk of strong winds in places. These conditions will gradually spread across the UK on Saturday, with Sunday and Bank Holiday Monday likely seeing sunshine and showers.

“So, whilst the bank holiday won't be a complete washout, with some sunshine expected, this weekend represents a notable shift from the fine and settled weather pattern that has dominated so far this month.”

As we head into the half-term week, conditions are ‘likely to remain unsettled’, the Met Office warned – with rain and wind in the forecast.