Weather Report

Weather patterns need to get more love in Fictionland.
It's one of those essential facets of what makes a setting unique, but often gets put aside unless the weather is being used to cause conflict or set a mood.
I'm not arguing that your novel should include constant updates about the weather. However, it should not be a forgotten aspect of the setting; furthermore, wildly improbable weather patterns or weather that's atypical of your setting will potentially scupper suspension of disbelief, unless there's some in-universe explanation. 
Don't just manipulate the climate in your setting to add dramatic emphasis (it was a dark and stormy night!) or cause conflict-- rather, think about how the characters interact with the weather as it would be naturally. Their mood could cause them to see the falling January snow as a cozy blanket, or as leaching away the colour from the outside world, or as freezing everything into stasis. The same snow, but viewed though the lens of the story and characters.
Also, think about the climate patterns and what that means for your characters. Rather than stir up a freak August snowstorm (or February, if you're in Argentina) why the characters traveling in winter (or the appropriate snow season for your setting). Did they intend to? Are they prepared? Maybe they came from a tropical latitude, and are totally taken aback by the snow, or maybe they got suddenly delayed. Think about the characters as having a relationship with the world around them, rather than the world (particularly the weather) acting around the characters. [image error]