January in Oneonta is the windiest and the coldest month of the year. In January, the weather in Oneonta is typically cold. Average daily high temperature in January is about 8 degrees above zero. On average, Oneonta has 12 sunny, 9 rainy, 9 partly cloudy, and 1 cloudy day in January. The rains are usually heavy. January as well as February, July, and December is considered the most uncomfortable time to visit Oneonta.