It's the time of the season where the NFL can start flexing games into primetime. During weeks 5-10, the NFL can flex up to 2 Sunday afternoon games into prime time if they think that game is more interesting than the game that is already there.
There is a 12-day advance notice required to flex the game, so week 5's game(KC@Houston) will not be changed. I think all 5 of these games are with good enough teams that will be fairly competitive. Week 9 is probably the weakest match-up, especially if those teams do not look good in the next few weeks. However, there is not a stand-out game that day to replace it.
Bears and Packers are tonight. Sunday morning is another London game.