Turkey bought S-400 missiles from Russia
It's been a rough year for the Turkish lira and news of sanctions in the day ahead isn't going to help. Bloomberg cites people familiar who say that Trump has signed off on a series of sanctions against Turkey for buying Russian missiles.
The details of these sanctions are going to be important. If they're against individuals then it doesn't matter; that's basically a token gesture. However if they're against the country then TRY could have a problem. So far the reaction has been negligible.