adjective
BAD : The summer in Japan is very hot and damp.
GOOD : The summer in Japan is very hot and humid.
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damp = slightly wet, especially in a cold and unpleasant way: 'Our hotel room felt cold and damp.' 'On damp days, we have to dry the washing indoors.'
humid = warm and full of water vapour: 'The air in tropical forests is extremely humid.' 'I didn't expect Singapore to be so humid.'