Be careful, there's trouble coming.
It means Get prepared for an imminent threat.
It was/is called a bar. The expression "Katie, bar the door" comes directly from this usage. Up until the early 20th century, this was a common method of securing a door for the night.
This is more commonly said as "Katy" or "Katie" - it means to take precautions because trouble is coming. To "bar" a door is to fasten the lock. This is an Americanism that has been around since the 1800's, but the actual origin is unclear.
Next Door with Katie Brown - 1998 Fuss Free was released on: USA: 24 January 2000
To bar someone at the door of a night club means they are not allowed into the night club. also a guy might say I have a bar (As in erection)
Next Door with Katie Brown - 1998 Into the Light was released on: USA: 4 December 1999
Next Door with Katie Brown - 1998 Apples was released on: USA: 1 May 1999
Next Door with Katie Brown - 1998 For the Birds was released on: USA: 21 April 1999
Katie Sketch owns a bar in Toronto together with her ex-band mate Jenny Smyth.
Katie MacDonald
The name Katie does not have a direct translation in Polish, but it could be associated with the name Katarzyna, which is the Polish equivalent of Katherine.
Next Door with Katie Brown - 1998 The Perfect Gift was released on: USA: 8 February 2000