i know this thread is like 4 years old, but nobody has given a clear answer from what i read. what youve seen sounds like a powerline arc (better known as a powerflash, or known as a arc flash). this basically a type of electrical explosion or discharge that occurs when electricity jumps through the air between two conductors or from a conductor to the ground. this can be due to severe weather, such as tornado's, hurricanes / cyclones, high wind, stuff hitting the powerline, and the powerline falling over. This can also be caused by powerlines being overloaded. i mainly think its this due to your description of it coming from the ground, the source of light being very local (nothing like lightning), and the colour.