In chapter 14 of And Then There Were None, the weather is quite pleasant. Obviously, the circumstances on the island are something like the opposite of pleasant. However, the weather appears to be rather agreeable. The narrator tells the reader that “the wind had died down completely and the sky must have cleared.”

The implications of the nice weather are extensive. You might start off by talking about how the nice weather reinforces the isolation and paranoia of the four remaining guests. Remember, at the start of this chapter, the four living guests lock themselves in their own rooms. They’re forced to be by themselves with their own thoughts and speculations about what’s happening.

It’s almost as if the lack of tumultuous weather in chapter 14 serves as a reminder for how helpless the four remaining guests are. They’re on the island because of choices they made. There doesn't seem to be any external influence coming to their rescue. The burden falls squarely on them. Christie, at least in chapter 14, doesn’t even give her four remaining characters the benefit of a storm or rainfall that might temporarily distract them from their sinister situation.

You could also talk about the implications of the moonlight in chapter 14. Remember, Blore says it’s “clear as day” due to the strong moonlight. You could say that the moonlight lets Blore and Lombard look for Armstrong on the island. If not for the moonlight, it might not be so clear where Armstrong is or isn’t. The moonlight allows them to get some certainty about the whereabouts of Armstrong. Alas, that certainty appears to only stir up more mystery.