Definition
A pilot's deliberate review of current and forecast weather conditions along a planned route of flight, conducted before departure and updated en route, to confirm that conditions remain within the pilot's and aircraft's capabilities and within legal flight rule minimums.
Plain English
Looking at the weather — at the airport, along the route, and at the destination — to make sure flying is safe and legal before going, and continuing to keep an eye on it during the flight.
Context Anchor
Used during preflight planning, before takeoff, and anytime changing weather may affect the flight.
Derivation
“Weather” comes from an old word meaning the state of the air. “Check” here means to examine or verify, not to stop something. Together, “weather check” means verifying the air and sky conditions before making a flight decision.
Why Pilots Care
It directly affects go/no-go decisions and helps avoid encounters with hazardous conditions such as low ceilings, strong winds, or icing.
Intuition Check
Do not read “weather check” as just looking out the window. In aviation, it means using reliable weather information and your own observations to make a safe go, no-go, or change-of-plan decision.
Example Sentence 1
During his preflight, Marco completed a weather check and found that ceilings at his destination were forecast to drop below VFR minimums by mid-afternoon.
Example Sentence 2
Mid-flight the pilot radioed flight service for an updated weather check to confirm conditions at the alternate airport.