The future of Categorical Amendment Criteria in support of aviation services

Categorical Amendment Criteria (CAC) is aimed at improving aviation forecast services to all customers who use the Terminal Aerodrome Forecast (TAF) for flight planning purposes. CAC accomplishes this by tailoring ceiling and visibility criteria to meet specific airport requirements, grouping them together into categories to match FAA Regulations, and checking TEMPO groups immediately against METARS to notify forecasters of resulting customer impacts. CAC is scheduled to replace standard amendment procedures currently outlined in National Weather Service Directive by the end of calendar year 2011.