Simulators like LTSpice allow the power generated by dissipative components to be computed for the individual parts in free air allowing the total power dissipation of the system to be found.
However, power dissipation and temperature rise are not simply related, for example, once the schematic is transferred to a physical layout on a PCB, heat transfer comes into play. Electronic assemblies are normally on a PCB in an enclosure, heat transfer in the PCB and in air will elevate the temperature of adjacent components, change the efficiency of heat sinking, and the whole board will be affected by the orientation, air flow etc. in an enclosure. Ambient temperature comes into play here as well.
Therefore it is normal practise to only worry about the power dissipated by higher power devices, and their relationship to the rest of the PCB, i.e. are there other parts that need good thermal stability, which may include such things as precision resistors and op amps. This is where experience comes into play.
Perhaps the most realistic way is to use a simulator based on finite element analysis, which adds a further quite complex layer to the simulation, and is based on the physical layout of the PCB .
Therefore the simple answer is that it is not generally possible from the schematic to work out what the actual temperature rise will be with any certainty, but the power dissipation certainly can be, and if that is low enough, then the temperature rise may be inconsequential. Not knowing what you are trying to achieve I really can't comment any further.
Cheers,
Richard
