CONDITIONALS

If you carry an umbrella, you won't get wet.
If you don't carry an umbrella, you'll get wet.
Unless you carry an umbrella, you'll get wet.
You'll get wet unless you carry an umbrella.

You should carry an umbrella. Otherwise, you'll get wet.
You should carry an umbrella. On the other hand, you can wear a raincoat.
The other side of the coin is (that) it might not rain.