Figure 6: As in Figure 4 but for the incremental horizontal velocity (arrows) and incremental potential temperature (contours every 1 degree, dashed for negative values) in the boundary layer (at z = 0.5 km) from (a) the 10-minute prediction (integrated from the analysis at 2108 UTC) in Test 1 and (b) the third analysis in Test 3 with respect to those produced by the control run valid at 2118 UTC.