Strong gusts of wind are predicted to cause travel disruption with forecasters predicting gusts of up to 40-50mph.
Temperatures will range between 13C (55.4F) to 14C (57.2F) on Bank Holiday Monday, below normal temperatures for this time of year of closer to 16C (60.8F)
Meanwhile, today will continue to be cold for the time of year, with sunshine and scattered showers.
Temperatures will range between 10C (50F) and 13C (55.4F)
Met Office meteorologist Craig Snell, added: “Monday will see a bright start in the east.
“Rain will be moving in from the west in the morning and spread to all parts over the course of the day.
“The rain will be accompanied by strong winds.
The Met Office forecast is backed up by charts from The Weather Outlook showing large swathes of blue indicating rain covering the UK throughout the day.
The forecasting service described the outlook for tomorrow as the “Bank Holiday Monday horror show”.
Next week, the Met Office said that going into next week and towards polling day on Thursday the weather will return to a mixture of sunshine and showers.
Mr Snell added: “Going into next week we get rid of this area of low pressure around early Tuesday and go back to where we are now, a cold flow from the north with a mix of sunshine and showers.
“In the south, we might well see another band of rain coming in from the southwest so it might be a bit more gloomy and wet in the south of the UK but it’s a little bit uncertain.”
As of Friday, the UK had seen 218.8 hours of sunshine in April, making it the second sunniest on record.