While radar itself is a generally reliable tool for weather prediction, the signals must pass though multiple computers, networks, and internet routes before they reach the screen on a user's mobile device or computer.
As a result, there are occasional "blips" or data corruptions that can result in unusual and unpredictable display results. These resulting patterns may be anything from blank grid squares to light flashes.
The data-stream is self-correcting and should return to a correct display within several scan-cycles and data-refreshes, which may take 5-15 minutes depending upon the radar station involved.