The City of Boston is bracing for an intense bout of extreme heat set to take hold of the region this week. The National Weather Service in Boston/Norton has issued a Heat Advisory effective from tomorrow noon through Friday evening, cautioning of heat index values that may reach as high as 104 degrees.

Residents have been advised to mitigate the upcoming swelter by staying indoors, preferably in air-conditioned environments, and to maintain hydration with ample fluids. This advisory emerges as NBC Boston reports the more temperate conditions of Monday will give way to a surge in temperatures starting Tuesday, escalating into a heatwave with consecutive days of 90-degree highs, peaking on Thursday with an anticipated 98 degrees. The mercury rise is accompanied by high humidity, rendering the air oppressive and the real-feel temperatures even hotter, particularly inland.

The extreme heat is expected to span across multiple areas including regions of northern Connecticut, central, eastern, northeastern, southeastern, and western Massachusetts, as well as northern Rhode Island. Nighttime relief will be scant as temperatures remain stubbornly elevated, with lows in the 70s, providing minimal reprieve from the day's scalding weather.

Greater Boston and the Merrimack Valley are already under an Excessive Heat Watch, underscoring the severity of the anticipated conditions. The elderly, children, and those with preexisting health conditions are especially vulnerable in such extreme weather scenarios, and local services are on alert for an increased demand on health and emergency provisions during the heatwave. The NWS forecast suggests a slight chance of showers and thunderstorms could offer a brief interruption to the relentless heat on Wednesday night and Friday, though chances for precipitation are variable.

As the city steels itself for the swelter, public health officials continue to stress the importance of taking preventative measures against heat-related illnesses. Community centers and public buildings are expected to extend hours and services to serve as cooling centers for those in need. The forthcoming days demand a level of preparedness and solidarity as Boston faces the furnace of this early summer heatwave.