What is the validity period for an FA weather forecast?

The validity period for a Flight Advisory (FA) weather forecast is indeed 18 to 24 hours. This time frame is critical for pilots and dispatchers as it provides a reliable forecast for the operational planning of flights.

The 18 to 24-hour range allows for sufficient time for pilots to anticipate potential weather changes that could affect their flight path, fuel decisions, and scheduling. This range is based on typical weather forecasting models and provides a balance between the detail needed for short-range weather and the inevitable uncertainties that arise in forecasting longer-term weather patterns.

While options like 12 to 15 hours may not provide enough breadth for comprehensive flight planning, and longer periods like 24 to 30 hours and beyond may compromise accuracy due to rapid shifts in weather, the 18 to 24-hour validity period strikes an essential balance, making it the most practical choice for aviation operations.