My hemoglobin has been on the high side for about 6 months at 16g/dl. red blood count is 4.95, white blood count is 7.1. my mchc is also on the high end at 35.3 g/dl. what could this indicate?

All laboratory results need to be interpreted in the clinical context and the doctor who ordered the tests is usually in the best position to do that. Talk to the doctor who ordered the tests. Having said that, hemoglobin may be elevated due to dehydration, lung disorder, residence at high altitude and polycythemia. If you level is stable it is not a cause for concern. Wish you good health!

Your blood work suggests polycythemia that most of the time is secondary to other conditions. Further work up will be needed, your current physician remains your best reference at this point.