Former Scunthorpe frontman Forte has yet to appear for Saints in the league so far this season but has scored twice in the Carling Cup.
He has been joined at Deepdale by 18-year-old Academy product Hoskins, who has top-scored for Southampton's under-18 team for the past two seasons.
Both players are available for Tuesday night's Johnstone's Paint Trophy meeting with Rochdale.
Hoskins will also be able to play in the FA Cup against Southend on Saturday but Forte will be ineligible to avoid becoming cup-tied.
Preston chairman Maurice Lindsay told the club's official website: "Jonathan is a quick and strong forward with experience at our level, whereas Sam is a young player with lots of potential, but his loan with us is more for his experience."