When I summon a fireball, typically with a high directional speed, the rate at which I assume it detects when it hits something isn't always in-sync with the fireball's position.
/summon Fireball -225 16 -425 {ExplosionPower:3,direction:[-5.0,0.0,0.0]} is one of the commands I tried. It seems to happen with any number depending on the distance it travels before hitting.
Marked this one as dupe of MC-92175 since that contains more information.