One of the most common dragonflies encountered this time of year in the northeast is the Autumn Meadowhawk, Sympetrum vicinum (formerly known as Yellow-legged Meadowhawk). They emerge in late summer and are typically the last dragonfly around into November.
The males usually have red adbomens, but they may vary from orange to brown depending on the temperature. The thorax and face are brown to black. The males have minimal black markings on the abdoment, separating them from another common red skimmer, Needham's Skimmer. The male's legs are yellow or brown, but never black. The females have a brown thorax and a brownish red abdomen.
They have a habit of flying far away from water so they can turn up anywhere. They also like to perch on clothing, so you may find one clinging to you on a late fall day. The Latin name for this genus, Sympetrum, means "with rock" and refers to their habit of basking on rocks to absorb heat early in the day.
A similar, less common species, that may be encountered is the Saffron-winged Meadowhawk.
Thanks to Susie from JerseyBirds for the pic.