Designed to alert drivers when schoolchildren are present, especially in low-visibility conditions, school-zone flasher signals are typically updated manually at each school. The switching is based on the school calendar and manually changed when an unexpected early dismissal occurs, as in the case of a weather-event altering the normal schedule. The process to reprogram the flashers requires a significant effort by school district personnel to implement due to the large number of warning flashers installed across an entire school district.