There was developed 1.5 D-model of relativistic runaway electron avalanche (RREA) in selfconsistent electric field above thundercloud. Multigroup approach was adopted to simulate runaway electrons. Luminosity of optical emissions into 1P and 2P bands of N2 and 1N band of N2+ above thundercloud was calculated. It was shown that Blue Jets are excited directly by RREA, Red Sprites are produced by low-energy background and secondary electrons, Elves are due to background electrons and their secondaries. Inherent to Red Sprites inhomogeneity was explained qualitatively. Computed magnitudes of the luminosity and space-time behavior of the luminescence appeared to be in agreement with observational data. The results obtained completely corroborated RREA capability to account for Blue Jets and Red Sprites and provided strong arguments in favor of the general idea of Roussel-Dupre and Gurevich on RREA.