Normal cloud formation is formed from the evaporation of water, whether from a body of water or over land from plants and animals alike. The moisture is lifted due to natural updrafts and combines with dust in the atmosphere to create clouds. The moisture freezes in the colder layers of the atmosphere, and the ice crystals reflect all light it interacts with, which is why clouds are white. Any number of different cloud types may result based on the conditions and location of the cloud formation.
Thunderstorm formation depends on the amount of moisture of an area, the strength of the updrafts, and the temperature. A warmer day will result in more powerful updrafts and a larger cloud height, often seen in thunderheads. Large updrafts are also seen around mountain ranges, which is why rain will fall on the mountains or the other side, an occurrence typically responsible for some desert conditions. This is because the large updrafts create bigger ice particles within the clouds from combinations through collisions, then on top or after, the updrafts are insufficient to keep the particles up and they fall from the formation. The pieces of ice that melt completely fall to earth as rain, while the other pieces that do not melt fall as hail.
An increase of temperatures around the planet create faster evaporation, stronger updrafts, and greater melting temperatures for falling ice pieces, which means greater occurrences of heavy rainfall. More lightning will result from these storms as the colliding ice particles are also responsible for charge generation within the thunderhead clouds. The stronger updrafts will create more collisions, which means more charges that will yield more lightning. As long as there is enough ambient ground temperature to create updrafts, these storms will form.
Another factor of temperature increase will do is manipulate the jet stream and create changing systems that would deliver more storms to a wider range of places. Changing weather patterns will mean more flooding in some places, while increasing drought and desertification from areas that are semi-arid and receive little additional rainfall. Older irrigation methods would also contribute to increased evaporation, which is why it is important to irrigate crops at night when it is less likely for evaporation to take place. Soil and then the plants, are more likely to retain the moisture compared to the day. Open holding ponds and urbanization of land also contributes to increased evaporation and less water that makes it into the ground, which results in more surface water over time, that will evaporate and create more storm systems.