Rain Foot
When precipitation cores hit the ground, some of it spreads outward along the edges, forming a flared bottom, also known in storm observer's lingo as a "rain foot." Rapidly moving ones -- especially if they raise scud clouds or dust, or are accompanied by power flashes -- signal damaging downbursts. In this case, however, the foot was kicking only slowly, and the outward rush of winds away from the core appeared to be non-severe. Being inside a rain foot, one can experience very heavy precipitation even though little or none is falling from the cloud base directly above.
S Hayes Center NE (12 Jun 7) looking S