Easterly often describes winds in weather reports, indicating a cooler climate due to eastward winds. The forecast says we'll have an easterly bringing rain this weekend.
Pro Tip 2/3
Not Always Literal
Easterly can describe any general movement from the east, not necessarily a strict eastward direction. The birds flew in an easterly across the sky, from northeast to southeast.
Pro Tip 3/3
Metaphorical Use
Easterly can be used metaphorically to suggest something, like a change, originating from the east. We felt an easterly shift in policy after the new leadership in the eastern headquarters.