Observation of electrometeors

(Section 3.3.5)

Records of lightning should include information about the type, intensity, frequency of flashes and the range of azimuths over which discharges are observed. Time between lightning and thunder should also be noted. Care should be taken to distinguish between lightning and its possible reflection on clouds or haze. In the case of Saint Elmo's fire, it should be stated whether the phenomenon appears in a cloud, precipitation, clear air, etc. Exceptional polar aurorae should be described in detail, accompanied if possible by photographs, time-lapse images or videos.