If you're dealing with temperatures, a better name than minval or minValueForTemperature might be mintemp, min_temp, or minTemp depending on your style. One reason to use moderately short variable names is so that reading the name is faster. Include the most important information in the name, infer the rest from context. If you find you still need a lot of context, drop something less important from the name (e.g. minval->mintemp).
I'd also avoid putting prepositions into variable names, but that's just a personal preference for keeping things to one adjective plus one noun where possible (less parsing overhead for my brain).
I'd also avoid putting prepositions into variable names, but that's just a personal preference for keeping things to one adjective plus one noun where possible (less parsing overhead for my brain).