A high-pressure system developing off the coast for the rest of the week will make the air especially humid and spawn scattered showers mixed with thunderstorms, forecasters say.

Skies will be cloudy with a chance of showers today. In the afternoon, there will be spurts of sunlight, but overnight, it is likely thunderstorms will pop up throughout the state, the National Weather Service says.

When an area sees sunlight over the next few days, it is likely rain will soon follow. Weather service meteorologist Charlie Foley said sun hitting an area will cause the air to heat up and rise. That rising air will then trigger showers or even a thunderstorm.

“With that sun comes the possibility that [people are] going to get wet,” he said.

Western parts of the state are expected to see more rain. If there are large thunderstorms, up to three inches of rain could fall. On average across the state, an inch of rain is expected to fall this week.

For the rest of the workweek, highs will linger in the low 70s along the coast and in the upper 70s in Western Massachusetts.

Saturday will be partly sunny and temperatures will rise to the mid-80s.

Sunday will also be in the 80s with a mix of sun and clouds.

“The majority of the holiday weekend looks to be favorable. The big question is Memorial Day itself,” said Foley.

A funnel system coming from the north may pull down temperatures and bring sunny skies, or it may keep temperatures high and lead to more clouds and showers, Foley said.