The possibility of measuring the neutral gas temperature profile of a weakly ionized plasma using ultraviolet Rayleigh scattering together with an atomic resonance filter containing mercury vapor is discussed. The plasma is illuminated with a high power, very narrow linewidth, pulsed ultraviolet laser, which is tuned into resonance with mercury atomic vapor. For density measurement, the laser is frequency tuned very close to the cut-off edge of the mercury vapor filter. Model calculations show that the temperature dependence of the signal ranges from T^0.8 to T^1.5. Since the measurements are made through an atomic vapor filter, imaging can be preserved, and a profile can be measured.