Charge separation during the rupture of small (1-2 mm) drops in the flow behind a shock wave was measured in a laboratory shock tube. The results are consistent with charge separation results measured for larger drops in steady airflows. Such charge separation could account for the lightning observed near volcanoes and above-ground thermonuclear explosions. A charge regeneration also occurs in common thunderstorms due to thunder-induced drop fragmentation, but this effect probably gives only a minor contributions to the charge distribution in a thundercloud.