The onset of the heat burst activity was also very rapid. Radar observations show the emergence of 11 descending pockets of reflectivity beneath the anvil base, close to the convergent flow region of the MCV. Individual cells about 4 km in diameter exhibited a relatively uniform spacing of 5-8 km within a 30 x 30 km domain. Corresponding surface-based videos at this location and time recorded multiple microbursts associated within the reflectivity cells (15-20 dBZ) that descended to low levels in the form of dry microbursts. The large number of microbursts over such a small region resulted in numerous inferred collisions of microburst outflows, and the spin-up of relatively intense vortices, two of which were sampled in the surface time series. The picture that emerges during the height of this activity is an extremely turbulent, deep, and chaotic boundary layer.
The surface instruments recorded very warm (T = 36 aC) and dry (Td = -2 aC; relative humidity of 8%) air. A maximum wind gust of 32 m/s was associated with a microburst, while a secondary wind gust of 24 m/s was measured near the outer periphery of a vortex that passed just south of the observation location.