Fortunately what you said applies mostly to LGA. JFK generally is able to manage some level of snow.


With severe snow/ice storms, the big risk to aircraft is not being able to fly for days while the airport runways, taxiways, and ramps are out of service. I remember during one of the crazy storms of a couple of winters ago, AA sent all the 762s out to LAX and SFO and they sat there for at least 48 hours, until JFK was ready to receive flights again. No flights in the interim.

Tropical storms are different....serious aircraft damage can occur from flying debris. But the response might be the same--it would make sense for AA to keep aircraft clear of the affected regions by storing them elsewhere in the system. So I suspect that most of the cancellations to/from MIA resulted in the equipment sitting at the OTHER hubs/focus cities in the system.....NYC, CHI, WAS, LAX, etc....maybe even some outstations.