You should bring your umbrella...

...just in case.

Today we will be looking at this expression. Have you heard it before? It is often used by parents, teachers and friends when giving advice or suggestions about what you should do. Most often, the case we are talking about is not mentioned because it is clear from the context.

You should call her before going to her place just in case.
(...she is out and you waste your time)

You should bring an umbrella just in case.
(it rains)

Billy bring your jacket just in case.
(you get cold)

According to bablefish, the online translation program ,it means ちょうど場合で. A more formal way to say the same thing is: to be on the safe side. Which babelfish translates as: 大事を取って.

You should go to the station now to be on the safe side.
(so you don't miss your train)

Tom don't forget to bring extra socks to be on safe side.
(so you don't run out of clean socks)

I always write down a grocery list before going to the store just to be on the safe side. (so I don't forget to buy anything)

So we use these two expressions in pretty much the same way. Have a nice weekend!

Phil