Pittsburgh endures cloudiest May in recent history

In May 2025, Pittsburgh, Pennsylvania, faced an unusually high number of cloudy days, contrasting with its typically fluctuating weather patterns. This month recorded 18 cloudy or mostly cloudy days, significantly surpassing the usual average of 17 cloudy days for May. Additionally, the city only saw two mostly sunny or completely sunny days, with some missing climate data from May 13 and 14 suggesting these days also leaned towards being cloudy. The statistics indicate a marked deviation from what Pittsburghers expect, demonstrating the city's infamous reputation for overcast conditions. Geographical factors contribute to Pittsburgh’s cloudiness, making it one of the cloudiest areas in the United States. Situated downwind from the Great Lakes, the city experiences frequent cloud formation, especially during the colder months. The interaction of cold air traveling over warmer lake waters creates atmospheric instability conducive to cloud development. Moreover, the hilly terrain of the Laurel Highlands allows moisture to rise, further promoting cloud formation in the region. As the month progressed, temperatures in Pittsburgh saw a decline during the last two weeks, averaging only 56.8 degrees Fahrenheit, which was well below average. However, warmer weather was anticipated to return shortly after the cooler stretch, with highs expected to reach the low 70s. This temperature fluctuation has shaped the local experience significantly, as residents await sunnier days. In summary, while Pittsburgh tends to have a high number of cloudy days throughout the year, May 2025 has presented an exceptional case of overcast weather, prompting discussions among locals about the extended lack of sunshine. This trend could potentially influence outdoor activities and general mood, as the city's inhabitants often cherish the few sunny days they receive in the spring and summer months.