Continuity mistake: When they first bring the girl to the house with the storm and lay her on the bead the there candles next to her. First the tallest one blows out then the middle one blow out then the shot changes and the middle candle blows out again.
Audio problem: In episode 1x08, "Swimming With Boyd", when Lucas is talking to Julie on the street, the audio looping as he says "Listen to me" is quite noticeable - his lips don't even come close to matching what we hear.
Factual error: Sarah's tour ends at Point Pleasant's light house. Point Pleasant, NJ, does not have a light house. The nearest one is in Sea Girt, about five miles away.
Factual error: When she's giving the historical tour, Sarah talks about how the Puritans who settled in Point Pleasant faced hardships during their first winter there. But the first village at Point Pleasant was built in 1817, a century and a half after Puritans ceased to exist as a distinct group.
Plot hole: In episode 1-7: "Unraveling," Christina and Jesse get on a bus to New Haven, first thing in the morning. Christina left the Kramers's house before breakfast. Then, they ride on the bus all day until getting trapped in a terrible storm in the dark of night. But New Haven, CT, is less than a seven hour bus ride from the Jersey shore, so anything that happened to them on the way there should have been in full daylight.