What is the maximum forecast period for AIRMETs?

What is the maximum forecast period for AIRMETs? The maximum forecast period is 4 hours for SIGMETs and 6 hours for AIRMETs. The G-AIRMET is issued over the CONUS every 6 hours, valid at 3-hour increments through 12 hours with optional forecasts possible during the first 6 hours. How long are AIRMETs valid for? six … Continue reading What is the maximum forecast period for AIRMETs?