The CSU/CHILL radar operated from about 1843Z, 20 July to 0315Z, 21 July. The STEPS area was included in SPC's moderate severe weather risk and a tornado watch was issued for most of the afternoon. Initial storm development was along a line extending roughly from Ft. Morgan through Limon to Colorado Springs. These storms had only a slow eastward progression; at least two of the storms were observed to split. The CSU hailstone van eventually took data at Anton CO, approximately 100 km NW of CHILL. They observed heavy rain and a few small hailstones. At this same time, new echo development began to occur along an east-west axis near Idalia. These storms grew to become the primary convection in the area. They eventually formed an east-west oriented squall line that crossed both Burlington CO and Goodland KS. Very high rainfall rates were observed at CHILL. Additionally, total differential propagation phase shifts greater than 200 degrees were observed when the CHILL viewing azimuths were along the axis of the convective line. STEPS operations ended as the squall line exited the area. It persisted overnight, becoming the fourth consecutive overnight MCS with origins in the STEPS domain.