Poor graduate student to Principal Investigator (PI) ratio.
PIs with anger and behavioral issues that are protected by tenure, no matter how inappropriate they are or what they do to graduate students.
Lack of activities (other than drinking downtown) outside of work hours. If you like to drink, then Downtown Syracuse is the place for you - areas outside of Downtown are unsafe. Food options are not great and lack diversity.
Source of stipend: graduate students receive a stipend that just covers the cost of rent and utilities and not much else. Graduate students receive that stipend in one of two ways: the Foundation or through the State of NY. For their first year, all students are paid through the State of NY. After you join a lab (usually end of year 1), you are usually paid through the Foundation (which comes out of your lab's pocket). If your lab is running out of $$, your PI may try to prevent you from passing your qualifying exam so that you are no longer a mouth to feed. But of course those PIs were willing to have you rotate in their lab because you were being paid by the State of NY (not their pocket) and they will tend to take on multiple rotating graduate students at once, and those graduate students have to compete for 1 space. If your PI decides to keep you in their lab but has no money, then you would have to be paid by the State of NY, which would be dipping into the money that is used to pay 1st year graduate students. This means that if you take longer than 1 year to find a lab that's the right fit or you need to change labs at 2nd or 3rd year, the Graduate Program will make little effort to help you find a lab.
The snow. And the snow, which goes from ~end of Oct - May. Don't be shocked if you see snow on Mother's Day. Even after salting, walkways within and around the Graduate School are extremely icy, slippery, and soupy. Be careful.