We have described thermal responses of jumping (Forms I and III) and blasting (Form II) in dichloro N-salicylidene (compound A) polymorphs due to the sudden phase transition at high temperature. The bromo and iodo halogen derivatives did not exhibit any thermal responses. The significance of weaker Cl⋯O interactions in an invariant amide dimer N—H⋯O structural family of polymorphs is the reason ascribed to the mechanical response of chloromolecular crystals. This study demonstrates the utility of hydrogen- and halogen-bonded molecular crystals in exhibiting the thermosalient effect under thermal stress and also presents a rationale for the design of thermoresponsive crystals.