In almost all instances, super-cell thunderstorms that produce long-track, dangerous tornadoes move to the northeast. But, on this day in history, the storms that were part of a deadly outbreak in Central Texas moved in the opposite direction.
A weather phenomenon known as a mesoscale convective complex developed over the Midwestern United States on May 27, 1997. An outflow boundary from that storm stalled out over Texas.
Super-cell thunderstorms developed along the line and followed along it, causing them to move in an atypical fashion to the southwest.
One of these tornadoes would be rated an F5 and impact the community of Jarrell, Texas. This slow-moving tornado would prove to be extremely destructive and deadly, completely destroying a subdivision of Jarrell, debarking trees, sending cars hundreds to thousands of meters through the air, snapping power lines and even tearing asphalt directly off the roadway.
Nineteen other tornadoes were produced by this storm system, five total F3 or above.