["Huge" sounds about like what Jon has been hearing so far, so his thoughtful expression turns, all at once, grim and dismayed.]

I hear it too. Think we can get them to take the horses and go, or stand back?

[The townspeople, so far -- among them a girl he recognizes from a tavern and a man who sells fruit in the market -- seem disinclined to move, but he doubts this will still be the case when a large creature with snake-like limbs and an orb for a body makes an appearance.

He turns to the crowd, raises his voice to the boom he would use to command troops, or quiet an assembly of fractious Northern lords.]

If something comes, we cannot aid you if the press of the crowd is too close.

[He's not sure that he's been heard, though.]