[weather eye] {n.}
1. Eyes that can tell what the weather will be.
* /Grandfather's weather eye always tells him when it will rain./
2. Eyes ready or quick to see; careful watch. — Usually used in phrases like "keep a weather eye on", "open", or "out for".
* /Mrs. Brown kept a weather eye on the children so they wouldn't hurt each other./* /Keep a weather eye out for Uncle George at the store./* /Keep a weather eye open for deer./* /The police have a weather eye out for the robbers./
Compare: LOOK OUT.