There is no universal answer to this.

There are a few sites that will do future fare estimates -- like Kayak, Skyscanner, AirfareWatchDog, Farecompare, ....

A lot depends to future sales: if seats don't selling as the airline would like, then fares may drop; if sales are doing good, prices may raise further.

Basic supply and demand (well a bit more than "basic" but similiar).