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**Figure 12:** Vertical cross-sections of the different polarization variables through the center of a small but intense New Mexico storm, at 15:20:37 MST on September 15, 1998. The vertical and horizontal distance scales are in km above and from the radar, respectively. The color bars show the data values in the indicated units. The lower right panel shows range profiles of the different quantities along the path of the radial cursor. The vertical scale of each profile is as indicated by the vertical color bar, except for the $\phi$ profile, whose total vertical scale was $90^\circ$ ( $5.6^\circ$ per tic mark).
$\begin{figure} \begin{center} \epsfig{file=figure1.eps}\end{center}\end{figure}$

**Figure 13:** A vertical cross-section through the same storm as Figure 12, at the same azimuth but 3 minutes later at time 15:23:05, and showing the polarization trajectory on the Poincaré sphere.
$\begin{figure} \begin{center} \epsfig{file=figure3.eps}\end{center}\end{figure}$

**Figure 14:** Same as Figure 13, but another 3 minutes later in the storm, at 15:26:35. Note the permanent decrease in $\rho _{HV}$ on the far side of the main precipitation shaft, indicating that the radar signal developed a unpolarized component in propagating through the precipitation shaft.
$\begin{figure} \begin{center} \epsfig{file=figure4.eps}\end{center}\end{figure}$

**Figure 15:** Observations of vertical electrical alignment in the upper part of the north side of storm, at 15:25:43. The alignment region is indicated by the dark radial band in the $\phi$ panel (upper middle) and by the red/blue region in the alignment direction panel (lower middle).
$\begin{figure} \begin{center} \epsfig{file=ad_plot4.eps}\end{center}\end{figure}$

**Figure 16:** Alignment direction vectors at three ranges from the radar, reconstructed from a three-dimensional volume scan of the storm between 15:24:07 and 15:27:18. The observations are in a plane perpendicular to the scan plane of the radar and show the storm as it would be viewed from the radar location. Vertical or near-vertical alignment is indicated by the black lines and shows strong electrification in the upper part of the leftmost precipitation shaft, and in the middle upper part of the main precipitation region (see text). The altitudes are now in kilometers above mean sea level.
$\begin{figure} \begin{center} \epsfig{file=trimap.eps}\end{center}\end{figure}$