Definition
A system that provides pilots and dispatchers with current and forecast weather information across a flight's route, including conditions such as icing, turbulence, thunderstorms, winds aloft, and altimeter settings, used to support decisions about route, altitude, and the lowest usable flight level.
Plain English
A weather tool that pulls together up-to-date weather along the planned route so pilots can see what's happening and decide how to fly through it safely.
Context Anchor
Seen in instrument flight planning and altitude-selection discussions, especially where pressure information affects the lowest flight level that may be used.
Derivation
"Enhanced" simply means improved or expanded — this system goes beyond a single weather report by combining many sources into one route-based picture.
Why Pilots Care
Accurate weather data from this system prevents choosing unsafe flight levels that could lead to icing or turbulence.
Grounding Statement
This term points to an approved source of weather and pressure information, not just a general weather display.
Intuition Check
Do not read “enhanced” as simply meaning “better” or “more detailed.” Here it means a specific approved system for supplying operational weather information.
Example Sentence 1
Before departure, the dispatcher reviewed the Enhanced Weather Information System to check for low altimeter settings along the route.
Example Sentence 2
Enhanced Weather Information System updates allowed for a lower flight level than initially planned due to improved pressure readings.