A speaker sits alone in a cold hut, hunched over a clock, and the short poem turns that small scene into a feeling of loss. The title promises "cold comfort," meaning a consolation that hardly consoles, and the poem delivers exactly that.
The clock is the center of everything. The speaker huddles over it almost the way you would huddle over a fire, as if it might give off warmth, but it only gives off the passing of time. Then it gets two harsh names: a "rogue theater" and a "thief." The first suggests the clock puts on a show that nobody asked for, drawing the eye and holding it. The second says what it takes: "wife and moons." Judging by those words, the speaker is separated from a wife, and the months are slipping away with her absence.
The mood is lonely, tense, and quietly bitter. Cold and waiting are felt in just a few lines.