State and federal officials want to know why the National Weather Service (NWS) didn’t issue a tornado watch before deadly twisters hit southwest Michigan on March 6, 2026.A supercell thunderstorm developed rapidly over Cass County, spawning four tornadoes. The strongest tornado, with winds up to 160 mph, killed three people in Union City, MI in Branch County. Michigan senators Gary Peters and Elissa Slotkin wrote a letter to NWS Director Ken Gr…