Thunder and showers are expected across the country today, according to the Met Office .
Forecasters predict rainfall throughout the day and potentially even thunder in some parts of the UK.
There will likely be heavy rain for the next few days, with downpours likely on Tuesday, Wednesday and Thursday.
Temperatures are set to average 20C in London today, although they could drop to 10C in some parts of Scotland.
Windy weather can be expected in certain places, although there will also be sunshine continuing this weekend's warm weather .
The north will bear the brunt of the bad weather, with temperatures dropping below 13C in some areas.
Downpours will get worse on Tuesday with large swathes of the country facing wet conditions, although there will still be sunny spells.
Forecasters think the mercury will drop to 19C in London and below 10C in Scotland on Tuesday, with thunder likely in certain areas.
The south of england and the north can expect temperatures between the low and mid teens.
Tony Wardle, the Met Office's deputy chief meteorologist, said: "By Monday it’ll feel notably cooler as fresher air from the Atlantic spreads to all parts of the UK.
"There’ll be frequent showers and some heavy, thundery bursts at times too, although it’ll be drier and brighter in the south at times, with some sunny spells. "
Conditions will not improve towards the end of the week as the wet weather is set to continue, with Thursday set to be a complete washout.
