It's sunset, and you don't really have a fire going yet, and you are right outside their range of vision, so they know you're there, but they can't make you out too good. (Ever seen Reign of Fire? Remember the "magic hour" same idea here...?
ok, so Sleet Storm, Javelin of Lightning, and what is Demetrius doing? Also, the npc's are technically at your command, so what do you want them to do? (Lorethel still has 8 charges from his Call Lightning spell from before, just an fyi...)