  We investigate the effects of strain on a crystal surface close to the bulk
melting temperature T_m, where surface melting usually sets in. Strain lowers
the bulk melting point, so that at a fixed temperature below but close to T_m
the thickness of the quasi-liquid film is expected to grow with strain,
irrespective of sign. In addition, a strain-induced solid surface free energy
increase/decrease takes place, favoring/disfavoring surface melting depending
on the sign of strain relative to surface stress. In the latter case one can
produce a strain-induced prewetting transition, where for increasing
temperature the liquid film suddenly jumps from zero to a finite thickness.
This phenomenology is illustrated by a realistic molecular dynamics simulation
of strained Al(110).
