Spotting JFK these next couple of weeks

Hello,
I'm in town until the 6th of january and I was wondering, if the weather allows it, if someone could help me with some of the spotting points in JFK and/or LGA?

Last Saturday it took me about 2 and a half hours to get to the approach of runway 31L. I managed to take some good pictures from the Costco parking lot and security there were quite nice. However, I didn't see not one spotter even though I know now that a few of you where in the area :p

Thanks!

Pedro.-