I think the latter has a correct sentence structure, though I think 天気は暑いから is much clearer as a first part.
The first sentence should be treated like the sentence order of のに, so cause before, then consequence after the keyword.
Also, to say that an action is some adverb, it would be better to use こと in the structure. For example, ご飯を食べる is “to eat rice”, while ご飯を食べること is the concept of eating rice. So if I wanted to say that eating rice is amazing, I would say ご飯を食べることがすごいです
Similarly, I think a better structure for your sentence would be
Another option is to simply use the structure of Verb[stem] + にくい which means “it’s hard to verb”.
Hope that helps