Clear skies should follow fog this morning, but an approaching cold front will bring showers and thunderstorms by midweek, said National Weather Service meteorologist Bill Gartner.
"Sunday's nice weather will hold out for one or two more days, with a weak front coming through about midweek, bringing with it the chance of showers or thunderstorms," he said.
It will be mostly sunny today with fog in the morning and highs in the low 70s, Gartner said.
"Nights are getting longer and cooler, but it will get pretty warm this week with highs in the 80s Tuesday and a high near 90 Wednesday, so we will go back to summer for a day or two," he added.
Following the midweek warmth, it will cool off again to the low 70s Friday and Saturday with a "good deal of sunshine."
According to Gartner, ups and downs like this are normal for this time of year.
"We cool off for a couple days and then it is not unusual for it to get warm again," he said.
The front approaching will cross New England, bringing storms through, then another big area of high pressure looks to move in through the end of the week and into next weekend, Gartner added.