Warbler Guy, is it common to see warblers during the winter? Are sightings of non-breeding season warblers typical in the East and Midwest?

Greg (in Baltimore), I could provide you details, yet definitely not better than the following fine article at Nemesis Bird that provides an explanation of "winter" warbler abundance for the East:

http://www.nemesisbird.com/birding/rarities/winter-warblers/

As for the West, say, in northern California where I live, the most typical warbler species to see (from most common to rarest in the order shown below) include:

- Yellow-rumped (both Myrtle and Audubon's subspecies occur in diverse habitats in great abundance, though Audubon's far outnumber the former);
- Common Yellowthroat (considered a resident throughout parts of n. CA, including the SF Bay Area) (male, immediately below and female below the male);

- Orange-crowned (although most depart annually be each autumn, a small number remain throughout the non-breeding season before they are again joined by returning migrants in February/March);
- Hermit (similar in abundance to the explanation noted for Orange-crowned, above);
- Palm (rare to absent during the non-breeding season, though often seen during the fall migration window....considered a vagrant sighting by many birders who observe this species in n. CA);
- Wilson's (even less common to detect during the non-breeding season than Orange-crowned and Hermit);
- Nashville (a few occur during the non-breeding season, but it's typically rare to absent)
- Black-throated Grey (rare to absent during the non-breeding season); and
- Yellow (although this species is common to see as a fall migrant throughout much of n. CA, it is usually rare to absent by November - March in this region).