It could be because it is summer. Many dogs (and other animals for that matter) shed their winter coats in favor of a lighter, cooler coat for the summer. some dogs, such as Siberian Husky?s or Great Pyrenees, have double coats, so when they shed it can come off in big clumps. If it seems to be year round, which typically occurs with indoor dogs, It could be because of the contrast between the outdoor and indoor climate.With the artificial climate inside, their natural body regulation gets thrown off balance when they step outside and experience a sudden change in weather. Because this takes place every time they go in and out, their body registers smaller changes, thus the continuous light shedding.
Most dogs shed more in the warm weather months. And they'll shed again in the fall so they can grow in a thicker coat for winter. It's amazing how much fur they can lose and not be down to bare skin. If your dog is shedding unevenly and has patches of bare skin, you should take him to the vet. Could be something more going on than just regular shedding.
Some dogs shed a lot. It could be due to the change in weather since some grow fur when it?s cold and shed when it?s hot. If your dog stays indoors and it?s a seasonal shedder then it might shed a lot. You can go to http://www.dogbreedinfo.com/shedding.htm and http://www.2ndchance.info/dogshed.htm for more information. You should also go to a vet just to make sure everything is okay.