What is the primary service provided by EFAS?

The primary service provided by the En Route Flight Advisory Service (EFAS) is to offer weather advisories that are tailored specifically to the flight type, route, and altitude of aircraft. This service is crucial for pilots during their flight, as it helps them make informed decisions based on current weather conditions that may affect their safety and operational efficiency. EFAS generates real-time information regarding a range of weather phenomena, including turbulence, thunderstorms, and other significant weather events that could impact a flight.

This targeted advisory approach is essential for enhancing situational awareness and optimizing the flight experience, ensuring that pilots remain informed of any weather-related challenges throughout their journey. The other options, though related to weather services, do not capture the specific focus of EFAS, as it does not primarily provide passenger updates, surface reporting, or long-term forecasts but rather concentrates on the immediate weather impacts relevant to in-flight operations.