Storm chaser David Piano captured this amazing
'bolt from the blue' lightning flash from western Lake Ontario to
the Burlington, Ontario, area at
approx. 0541 UTC on 18 Jul 2015.
The flash was isolated in the Southern Ontario
Lightning Mapping Array database, and the resulting VHF 'sources'
and their evolution over time are shown above. The entire flash
occurred over approx. 1.5 seconds, with sources at
the beginning of the period shown in blue and sources at the end
shown in red. The part of the flash visible in the
photo extends rapidly from over the lake to the Burlington area to
the northwest. The green triangle shows where the
Canadian Lightning Detection Network (CLDN) detected a negative
cloud-to-ground (CG) flash. The green square
is the location of one of the SOLMA ground stations. The grey line
is the outline of western Lake Ontario.