The time-resolved discharge patterns generated in a gaseous dielectric breakdown (DB) are imaged using a fast optical imaging system ( approx 40 ns exposure time). The discharge patterns from various gases (He, air, and SF6) show general features consistent with their known dielectric strength. A new stochastic pattern-forming model that explicitly includes time is presented and is shown to produce theoretical DB patterns in qualitative agreement with the present experimental discharge patterns for air (N2). The stochastic DB model (with time) also provides an approximation to the discharge current, which is in good agreement with published current wave forms.Key words: gas discharge, electron scattering, fractal.