Thanksgiving in Baltimore could be anything: warm and dry/wet, cold and dry/wet, snow. Probably won't be bitter cold. Start checking your favorite weather site about week or so before you leave.

Lots of music happening in the Balt/Wash area. Start with the Baltimore Folk Song Society page
http://www.min.net/bfms/
and
The Folklore Society of Greater Washington page
http://www.fsgw.org/

Thanksgiving is not traditionally a time for gift-giving.