Kenyan Sharon Cherop took the women's title with an unofficial time of 2:31:49.
The men's race saw the top three spots awarded to Kenyan runners with Levy Matebo and Bernard Kipyego finishing second and third, respectively.
American Jason Hartman came in fourth.
Monday's forecast, with temperatures in the 80s, prompted race officials to issue warnings to the 27,000 registered participants ahead of the historic race.
More than 4,000 runners opted to skip the race, while several others dropped out as temperatures soared, WBZ-TV reported.
Geoffrey Mutai, Wesley Korir, Sharon Cherop, Kenyan runners, Bernard Kipyego, Boston Marathon, Levy Matebo, Jason Hartman, high temperatures, race record holder