Sunday night remains muggy and warm as a heat advisory from the National Weather Service stays in effect through Monday. Heading into Monday morning, temperatures start in the low 70s before quickly climbing back near 90, pushing heat index values near 100 once again. While most of Monday daytime stays dry, an approaching cold front from the west brings a line of strong to severe thunderstorms late Monday afternoon into the evening, starting across western Long Island, with risks of localized damaging wind gusts, frequent lightning, and heavy downpours that could impact the evening commute along the Long Island Expressway, Sunrise Highway, and the Long Island Rail Road.

A stray shower or storm remains possible early Tuesday morning before skies clear out and temperatures settle closer to normal in the mid-80s. Wednesday starts mostly fair before a strong cold front dropping down from Canada brings another round of rain and storms Wednesday evening into Thursday. Once that front moves through, a significant cool-down arrives just in time for the weekend, bringing sunshine, low humidity and crisp temperatures in the upper 70s to around 80 starting Friday.