What type of air does cold, dense air often converge with to form a thunderstorm

The type of air would be The cooler and denser air wedges under the less-dense warmer air,
When this air is lifted through the motion upward, it would cause the pressure on the cold front to be reduced. When there is enough moisture mixed within it, it will create Formation of Thunderstorms.

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen

Did you know it's illegal to own only one guinea pig in switzerland?   : )