Is there a way to redirect output to a file without buffering on unix/linux?

I have a long running batch process that outputs some debug and process information to stdout. If I just run from a terminal I can keep track of 'where it is' but then the data gets too much and scrolls off the screen. If I redirect to output to a file '> out.txt' I get the whole output eventually but it is buffered so I can no longer see what it is doing right now. Is there a way to redirect the