It's extremely hot outside. Used in the northeast of the United States of America mainly used by outside workers; construction workers, etc.

When somebody cuts a fart in a room with people in it and blames it on the Barking spider

When you fart real loud around other people and tell them that was a barkin spider

When someone is looking at any of your social networking sites (usually Facebook), being nosy. The "up" may drop in short sentences