Hey, I didn't get this one, but then I realised Dutch lets you say: "overday", just like English allows: "overnight". I wonder why we didn't keep: "overday"; it's more concise than having to say: "during the day".
Why doesn't this translate to "during the day, is it warm?" it sounds like it's asking, does the word Warm always have Het in front of it?
"Het" in this case is just "it" - as in English: "It's warm". But Dutch word order is indeed different, which is probably what's confusing you. In Dutch, the natural order is, in effect: "During the day is it warm". Unlike English, this does not make it a question. In older English (Shakespeare, King James Bible, old nursery rhymes etc.), the Dutch word order sometimes still survives.
Ah ok, so would it be like saying something similar to, “by golly is it warm!”
I'm not sure, because your example is still really a question, just not one that expects an answer. I'm trying to think of some examples for you.
In the English nursery rhyme, Little Jack Horner, he says: "What a good boy am I!"
He's boasting, not asking, although the subject/verb order is reversed compared to the modern way, which would be: "What a good boy I am!"
And to take a famous quotation from Shakespeare:
"Now is the winter of our discontent Made glorious summer by this sun of York".
Again, it's not a question, but if it was rewritten in modern word order (which I don't recommend, as it sounds terrible), it would read: "Now the winter of our discontent is made glorious summer by this sun of York". - the verb moves much further from the beginning.
So in Dutch and older forms of English, the word order "Nu is het warm"/"Now is it warm" is absolutely fine. In modern English, however, the verb moves: "Now it is warm". Don't assume Dutch has the same word order as modern English.