The influence of electrode temperature on the time delay of electrical breakdown in an argon-filled (13.3 mbar) diode at electrode temperatures of 300, 523 and 673K has been investigated by measuring the electrical breakdown time delay (t_d) dependence on both the time interval between two successive measurements ( tau ) ('memory curves') and the applied voltages (U_w). The results obtained show that values of t_d at 673K are about one order of magnitude smaller than those at 300K, whether cathode or anode was heated. It was shown that the complete curve t_d=f(U_w) moved towards smaller values of t_d with increasing temperature. Conclusions on the change with temperature of the temperature equilibrium concentration of metastables are drawn.