The Solomon Star newspaper reports the 20-year-old mother of two was working outside the family home in Baegu, North-East Malaita when she was struck, dying on the spot.
A close relative of the family told the paper the family was shocked by the incident and the entire community was in mourning.
A chief from a nearby village said the thunderstorm had raged over the area all of Tuesday and Wednesday.
It is unclear whether a police investigation will be launched into the death.
