Well, the main difference between caliente and caluroso is that Caluroso is only used when you are talking about the weather from some place or day and also can be used when you are talking about a welcome or a greeting , and Caliente is used when you talk about an object or weather also.
For example:
Es un día caluroso-weather
La playa es un lugar muy caluroso-weather
Le mando un caluroso abrazo-greeting
El día esta caliente-weather
El cafe esta caliente-object
La plancha esta caliente-object
caliente is the adjective of an object, instead of caluroso, it is a condition. You can't say "la taza de cafe esta calurosa". "Ayer estuvo caluroso" stats more for a weather condition.