As Hurricane Matthew intensified into a Category 5 storm in the Caribbean this weekend, the tempest also produced vibrant colors in the sky. The rare atmospheric phenomena, known as lighting sprites, were photographed by an observer about 400 miles southwest of Puerto Rico.

The lightning sprites were seen as fleeting flashes of brilliant red light above the clouds. (See the giant sprite observed from the space station.)

Sometimes called "upward lightning" and "cloud-to-stratospheric lightning," sprites are momentary bursts of electricity that can literally reach the edge of space, about 50 miles above the ground. They're rarely documented because they are so short lived (typically about 10 milliseconds) and are often obscured by clouds. In fact, evidence of sprites is