  The luminosities and effective temperatures, as well as the whole bolometric
lightcurves of nonlinear convective RR Lyrae models with 0.0001<Z<0.006 are
transformed into the SDSS photometric system. The obtained ugriz lightcurves,
mean magnitudes and colors, pulsation amplitudes and color-color loops are
shown and analytical relations connecting pulsational to intrinsic stellar
parameters, similarly to the ones currently used in the Johnson-Cousins
filters, are derived. Finally the behaviour in the color-color planes is
compared with available observations in the literature and possible systematic
uncertainties affecting this comparison are discussed.
