The deeply pained, often agonizingly somber mood of “The Outcasts of Poker Flat” at first seems at odds with the stiff, lawyerly tone of its narration. For example, at the end of the story, when the Duchess discovers that Mr Oakhurst has restocked their fuel enough for a couple more days' survival, the mood becomes very sentimental as it becomes clear that the remaining "outcasts" cannot survive:
[...] the Duchess, feeding the fire, found that some one had quietly piled beside the hut enough fuel to last a few days longer. The tears rose in her eyes, but she hid them from Piney. [...] That night the storm reached its greatest fury, and, rendering asunder the protecting pines, invaded the very hut.
The story by this point has become utterly tragic. The situations the characters find themselves in as they battle the elements are sad and hopeless, and the reader is presented with catastrophe after catastrophe as the “outcasts” careen towards a snowy death. Because of this, the mood is melancholy, and increasingly so. Oakhurst has replenished the fuel as a last act of bravery before departing into the storm for help, the Duchess is hiding her tears from Piney in an effort to prevent the younger girl from despairing, and even the minimal shelter of the hut has been destroyed by the ravenous tempest. The reader is made to feel both the harshness and "fury" of the environment which "rends" apart any shelter, and the concurrent brutality of the society in which the story is set.
Through this, the reader is nudged to think about whether the “outcasts” could possibly have deserved the hand they were dealt by fate. The dry, solemn voice of the narrator is also often juxtaposed with the melodramatic, emotional, and colorful language of these characters, as they bemoan their situations and attempt to help or hinder each other’s progress. The tone and mood of this piece initially contradict each other.
There are a few moments of light relief in "The Outcasts of Poker Flat," but even Tom’s stories of Achilles by the fire, or Piney’s unwitting closeness with the Duchess, a woman she’d never be allowed to speak to at home, are quickly followed by compounding difficulty and hopelessness. The "outcasts" encounter challenge after challenge from the weather, from the theft of their possessions, and from starvation, none of which are directly caused by their own actions or choices.
Toward the end of the story, as the mood and tone of the piece align, the mood becomes elegiac and reflective while still remaining morose. The tragedy inherent to Harte’s story encourages readers to think about the relationship between morality and goodness, and to decide that morality is not black and white, as the "secret committee" of Poker Flat has done. The story presents several characters (like the prostitutes The Duchess and Mother Shipton, for example) as “good” in this situation, although they are deemed “improper” by the town that has decided to exile them. The mood is emotionally provocative throughout, and forces the reader to question their own assumptions about the nature of people’s moral alignments.