Philadelphia’s Snow Drought: A Winter Without White
The city of Philadelphia experiences its longest snow drought in history, raising questions about the changing climate patterns and the absence of winter weather.
As winter settles in, Philadelphians are left wondering when they will see the familiar sight of snow-covered streets and the joy of building snowmen. It has been 668 days since the city has seen even an inch of snow, surpassing the previous record set in 1973. The absence of snow has left residents longing for the winter wonderland they once knew, and meteorologists are trying to understand the cause of this unprecedented snow drought.
A Winter of Snow Deprivation
The winter of 2022-23 in Philadelphia will go down in history as one of the least snowy seasons on record. With a mere 0.3 inches of snow, it finished second in the city’s all-time snow-deprivation derby. The lack of snow has had a significant impact on the city’s snow removal efforts, with PennDot’s Philadelphia region using a record low of 10,385 tons of salt on state roads, compared to the 10-year average of nearly 90,000 tons.
The Role of La Niña
Meteorologists believe that the absence of snow in Philadelphia can be attributed to the La Niña weather pattern in the tropical Pacific. For three consecutive winters, sea-surface temperatures in the region have been below normal, creating conditions that are not conducive to snowfall. The consistent cooling of the air over North America, driven by the west-to-east upper-level winds, has resulted in a lack of cold high pressure systems to the north of the region, which are necessary for the formation of snow from coastal storms.
The Traffic Light Theory
Bob Larson, a senior meteorologist with AccuWeather Inc., offers the “traffic light” theory to explain the lack of snow. According to Larson, it’s as if the cold air from the north has a red light when storms come along. The absence of extremely cold air and the consistent presence of warmer temperatures have prevented the necessary conditions for snowfall. Larson suggests that the only way for snow to occur is if the “lights malfunction,” which has not been the case in recent years.
Changes on the Horizon?
Contrary to the past three winters, the sea-surface temperatures in the tropical Pacific are now trending towards El Niño conditions, characterized by warmer temperatures. Long-range forecasters predict an active coastal storm track as winter progresses, but this does not necessarily guarantee snow for Philadelphia. During El Niño, the jet stream winds that bring snow and cold air to North America are often split into two branches, making it difficult for major snowstorms to occur unless the branches meet along the coast.
Conclusion: As Philadelphians endure another snowless winter, the question remains: when will the snow return? While the changing climate patterns and the absence of snow may be disheartening for winter enthusiasts, there is hope on the horizon. The transition from La Niña to El Niño conditions in the tropical Pacific may bring about a change in weather patterns, potentially leading to more snow in the future. Until then, residents will have to make do with memories of winters past and hope for a snow-filled future.