Isolated thunderstorms in mT air masses. Common in SE US summer. Lifting mechanism is thermal convection. Thunderstorms along a mountain front. Orographic lifting in summer time, as mT air lifted from Great Plains up into the Rockies.
Thunderstorms form along squall lines and associated cold fronts.
Strengthened by jet stream and strong thermal contrast. Especially prevalent in the spring. Some common features 1. Lightning is nothing but a rapid redistribution of electrons across this voltage gap. During mature stages of thundershowers, both updrafts and downdrafts are well developed.