Fig. 1. 3D volume rendering of simulated cloud water content in a 7.5 x 7.5 x 3 km sub-domain, showing the tornado condensation funnel reaching the ground. Bottom: time series data. Note that the above image was created by Greg Foss of PSC, using my simulation data created on a PSC machine. More recently, Xue completed a set of numerical simulations of tornadoes embedded within a supercell storm, using ARPS at up to 12.5 m horizontal resolution (Xue 2004; Xue 2006).
Figure 1a shows a 3D visualization of the volume rendered cloud vapor field, showing a well-defined condensation funnel, from a 25-m horizontal grid spacing (x) simulation initialized using the 20 May 1977 Del City, OK, storm sounding. When an even higher 12.5-m resolution is used, the tornado becomes more intense (reaching F5 intensity), giving sustained wind speed of over 120 m s-1 and maximum pressure drop of over 90 hPa.
