A MONTH'S worth of rain could fall in just a few hours in Essex as forecasters warn of possible "flash flooding" in the county.

The Met Office has issued a severe weather warning for rain, valid from midnight until noon on Tuesday.

Once a thundery storm from the continent arrives in the south-east of England, it will bring the risk of nearly an inch of rain in the space of an hour, which could become nearly three inches within a few hours.

The Met Office forecast said: "A band of rain, heavy and thundery in places, will spread westwards from the early hours of Tuesday morning.

"There is the risk that rain will turn torrential in places, with frequent lightning.

"Winds will also increase, with northerly gales on coasts. Whilst most places will miss the worst of the weather, please be aware of the risk of flash flooding.

"A thundery low over the continent will pass close to the southeast of England, bringing a band of rain with it.

"This is likely to contain thundery elements and locally very intense rain, bringing the risk of 20mm in the hour and more than 60mm in a few hours.

"As it comes west it should weaken, so the greatest risk of disruption is in eastern parts during the early hours."