Don’t the tornadoes usualy start a little east of tornado alley before settling in to the west later in the season?
Actually, it's more of a south to north movement - the tornadoes early in the season tend to strike in the south and the threat migrates north as we move into May and June. The difference this year is that the La Nina spring has kept Texas and Oklahoma below normal for outbreaks by moving storm systems farther north and east.
Our local NWS office is hinting of a major pattern change starting next week, which should finally allow Ohio to dry out.