Forecasters on Saturday predicted heavy rain for all of Leeds, Bradford, York, Harrogate, most of the Yorkshire coast and Barnsley.
Some flooding is possible, forecasters have warned, and there could be power cuts and poor driving conditions.
Although today will be largely clear in the morning, heavy rain is set to hit at about 11am to 1pm.
Some areas, like Sheffield, should avoid the worst of the rain.
What the Met Office says:
"A cooler feel to the day, with a moderate southwesterly breeze developing through the morning.
"Turning increasingly cloudy as outbreaks of rain push in from the west, turning locally heavy at times, before it clears east in the afternoon.
"Maximum temperature 18 °C."