This study demonstrates that, for British Romantic authors writing in the 1815 – 1820 period, autumn—with its frequently nebulous weather, its variated atmospheric aesthetics, and its cultural clout as the season of both fruitfulness and decay—was an apt aesthetico-temporal trope to represent the tempestuous climate—or spirit—of their age. I argue that Mary Shelley's Frankenstein (1818), Jane Austen's Persuasion (1818), and John Keats's To Autumn (1820) depict autumn as the season of missed time: an interval during which Victor Frankenstein, Anne Elliot, and Keats's speaker find themselves in states of melancholy suspension in time and space, which is generative, at worse, of paralyzing and alienating perplexity, and, at best, of alleviating and grounding sensoriality in the here-and-now. The autumnal aesthetics and temporality of the three texts, I suggest, represent Shelley's, Austen's, and Keats's literary engagement with, and response to the temporality of acceleration and contingency, as well as the climate of elusiveness and uncertainty of the age 1815 – 1820.