6.3 Amendment Criteria
Amendment criteria are specific meteorological element thresholds used to determine when TAFs should be amended (updated) due to changing or expected changes in conditions. When the weather conditions cross these thresholds, they can be operationally significant to air traffic managers, airline dispatchers and pilots.
Categorical Amendment Criteria (CAC)
The NWS worked with the FAA to implement ceiling and visibility criteria thresholds for each TAF site. The thresholds are based on the airport's "lowest standard approach minimums as published" that apply to the majority of the aircraft using that airport. These thresholds can be different for each airport depending on the amount of traffic flow, type of runway approach (precision or non-precision) and runway configurations.
Review Categorical Amendment Criteria (CAC) categories and thresholds.
Additional Amendment Criteria
In addition to the CAC for ceiling and visibility, there are amendment criteria for weather, wind and low-level wind shear (LLWS).
Review additional TAF Amendment Criteria.