Which environmental condition is least likely to contribute to the development of thunderstorms?

Stable air masses are least likely to contribute to the development of thunderstorms. Thunderstorms typically form when warm, moist air rises and cools, leading to cloud formation and precipitation. Stable air masses, by contrast, resist vertical motion and thus inhibit the rising of warm air at the surface. This stable condition tends to quench the atmospheric instabilities necessary for thunderstorms to develop.

On the other hand, high temperatures and excessive humidity can provide the energy and moisture needed for thunderstorms. In particular, high temperatures can create a significant temperature difference between the surface and the upper atmosphere, increasing the likelihood of instability. Low lifting mechanisms, such as fronts, mountain ranges, or sea breezes, can also facilitate the ascent of air and contribute to thunderstorm formation, making stable air masses the least conducive to such development.