Keep a weather eye on somebody/something

Pro Tip 1/3

The phrase is often used metaphorically, suggesting careful attention without implying actual weather.

As the debate heated up, the moderator kept a weather eye on both speakers.

Pro Tip 2/3

It implies a need for persistent vigilance, not just a single check.

With the recent increase in cyber attacks, IT managers must keep a weather eye on network security.

Pro Tip 3/3

The phrase originates from sailing, hinting that one should be ready to respond to changes.

As they approached the stormy cape, the captain kept a weather eye on the swells.