Seattle's winters are cool and unpredictable, with temperatures often fluctuating between freezing and mild, averaging around 5-7°C in January and February. As spring approaches, temperatures gradually warm up, reaching averages of 11-13°C by April and May. Summer months bring warmer days, with June to August experiencing average highs around 19-20°C, but still not hot by many standards. Autumn brings a return to cooler temperatures, with September's averages dipping back down to around 16°C before November's chill sets in once again. Winters are marked by cold snaps, with December often seeing the lowest temperatures of the year, averaging just 4°C.