Introduction
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Forecasters say there’s a growing chance of another winter storm heading into the weekend in the Philadelphia area.
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The National Weather Service says Philadelphia has a 20%-30% chance of experiencing a moderate winter storm.
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As of Tuesday, the path of the still-developing winter storm remained uncertain.
Philadelphia – As Philadelphia continues to emerge from the icy remains of last weekend’s winter storm, forecasters say another system may be forming.
Forecasters monitor the possibility of more snow in the Philadelphia area this weekend
The National Weather Service Prediction Center said it’s too early to know details but encouraged the public to monitor forecasts this week.
what we know
Forecasters say frigid temperatures will continue to blanket the eastern half of the United States next week. By Thursday, an “upper-level disturbance” will break out of Canada on Thursday and deepen over the eastern United States on Saturday.
This will result in a strong surface low pressure system interacting with the cold air mass. The result is heavy rainfall.
Fox weather forecasters said one important signal they observed with this setup was an atmospheric traffic jam over Greenland, which could force the storm to meander along the coast, causing multi-day weather hazards.
The second is an impressive ridge between the western mountains. While temperatures there will be well above average, it provides a clear path for the jet stream to carry the system out of Canada, across the plains, and out somewhere along the Atlantic coast. This also helps ensure that cold air continues to flow from the Arctic into the eastern half of the United States.
Arctic weather coming to eastern US (Fox Weather)
If the timing aligns over the weekend, the stage could be set for another snowstorm in the Northeast rather than another cross-country storm like we saw over the weekend.
local perspective
The National Weather Service on Monday predicted a 20%-30% chance of moderate winter storm impacts from the still-developing system.
Meanwhile, parts of South Jersey have a slightly higher chance of being affected by a winter storm this weekend, according to the weather service.
Moderate impacts include hazardous driving and winter weather-related disturbances, the weather service explained.
what we don’t know
As of Monday afternoon, the location, intensity and timing of the unrest from Canada remained unclear.
The timing, track and intensity of the surface low pressure system will determine whether the storm brings rain, snow or a mix of precipitation. It will also determine how much precipitation occurs in the eastern United States before the storm moves offshore.
It’s too early to determine the impact of wind and snow on travel and infrastructure.
What are the models saying?
With several days of data left to collect, computer forecast models have a large degree of uncertainty about the system’s outcome.
Fox Weather meteorologists Bob Van Dillen and Jane Minar noted on Monday that both traditional and AI-driven European forecast models indicate a greater impact on the mid-Atlantic coast, while the U.S. GFS forecast model is less optimistic about significant impacts.
Comparison of computer forecasting models. (Fox Weather)
But if those forecast factors combine, it could bring another snowstorm to the northeast of the Interstate 95 corridor, where many parts of the region are already suffering from a decade-long snow drought.
By the weekend, a jet stream pattern will allow a weak speedboat system to move out of Canada and bring lake effect snow to the Great Lakes and western New York State.