Measurements of local astroclimate parameters in specialized rooms of the Large Solar Vacuum Telescope (Baikal Astrophysical Observatory ISTP SB RAS) are presented. It is shown that temperature gradients in the telescope rooms cause a Benard cell and the incipience of the turbulence in the pavilion of astronomical spectrograph. It is shown that the measurements confirm main stochastic scenarios (Landau-Hopf, Ruelle-Takens, Feigenbaum, and Pomeau-Menneville). The bifurcation Feigenbaum diagram is confirmed experimentally. The main vortex in the Benar cell is decomposed into smaller ones as a result of ten period-doubling bifurcations. The incipient turbulence is stated to be almost determinate. The fractal character of the turbulence spectrum is found. The actual atmospheric turbulence is shown to be a mixture of determined vortices of different scales, observed in the incipient turbulence. It has been found that the incipient turbulence introduces large errors into spectral measurements. The horizontal random shifts of spectral lines, appearing due to the pavilion effects, can reach 1 arc-second. The incipient turbulence approximates to the regular refraction by its optical properties due to low frequencies of line shifts.