Natural disaster
A solar flare is a phenomenon where the Sun suddenly releases a great amount of solar radiation, much more than normal. Solar flares are unlikely to cause any direct injury, but can destroy electrical equipment. The potential of solar storms to cause disaster was seen during the 1859 Carrington event, which disrupted the telegraph network, and the March 1989 geomagnetic storm which blacked out Quebec. Some major known solar flares include the X20 event on August 16, 1989, and a similar flare on April 2, 2001. The most powerful flare ever recorded occurred on November 4, 2003 (estimated at between X40 and X45).
Hyder flare
A Hyder flare is slow, large-scale brightening that occurs in the solar chromosphere. It resembles a large but feeble solar flare and is identifiable as the signature of the sudden disappearance of a  solar prominence (a "disparition brusque"). 
These events occur in the quiet Sun, away from the active regions or sunspot groups, and typically in the polar crown filament zone. 
Hyder flares have a two-ribbon morphology and can be faintly observed in chromospheric emission lines such as Hα or as enhanced absorption in He I 1083 nm line.