ShakeAlert and similar systems are awesome, but not exactly what most folks mean by a prediction, FWIW. They're meant for warnings of seconds, but not for things on the scale of minutes or hours or days.
Not to take away from ShakeAlert in any way though! Just clarifying that in terms of another comment I made about earthquake precursor signals.
ShakeAlert and similar aren't about precursors, but instead are about "the earthquake has happened, let's tell folks before the damaging surface waves reach them".
I heard this on Audacy from the Philadelphia area.