Jon Snow has been mumbling about the coming cold for seven seasons, the citizens of King's Landing have been pulling their winter woollies out of the back closet and now it's finally time.
Cersei Lannister promised to join the fight against the White Walkers, but *psyche* she plans on reneging and leaving the rest of Westeros to fight them up north while she chills in King's Landing.
Tyrion Lannister has betrayed his fam, and is still advising Daenerys.
Jon Snow has pledged his allegiance to Daenerys (oh he pledged alright) and the two have officially entered the bone zone.
The undead have officially breached the wall and are marching south.
Daenerys' armies are on their way north and that means it's time for everyone to descend on Winterfell and take stock before the battle against the undead starts.