As the Philadelphia region deals with feels-like temperatures in the single digits and teens all day Tuesday, and even colder temps Wednesday morning, a significant winter storm could be on its way this weekend.
Looking ahead to Sunday and Monday, there are several factors that are still coming into focus.
1. We are highly confident the air will be cold enough with highs in the teens and low 20s all weekend and lows in the single digits and teens. It will be the coldest air of the season yet. Any snow will be at a high ratio due to the cold, meaning the colder the air, the more snow is squeezed out.
A 20:1 ratio means 20 inches of snow would be produced from 1 inch of water. In comparison, so far this season, we have seen wet snow with ratios of 6:1 and 8:1.
We will be in a 20:1 ratio for light, fluffy snow. So, if there is half an inch of water, we will see 10 inches. If there is a quarter inch, we will get 5 inches. If there is three quarters of an inch, we will see 15 inches.
2. The biggest factor in how much snow we receive is the storm track, and that is still our biggest uncertainty.
Currently, both long-range models show the storm center sliding through the Carolinas and northeast into the Atlantic. Here in Philadelphia, we could be on the northern edge of the storm or close to the center.
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3. Models have the snow totals all over the place and could range from a coating to 3 inches if we are on the far northern edge, with higher amounts south of the city.
If we are closer to the center of the storm, we could see significant amounts of 6 to 12 inches or higher across the entire area.
Again, the amount of snow is all about location, location and location. Someone in the mid-Atlantic will likely see monster snow numbers. Will it be Philly? It’s too soon to say, and here is why.
Just like the story of “Goldilocks and the Three Bears,” imagine the porridge as snow.
One model has heavy snow, one model has smaller snow, and one model has medium snow.
- The first long-range model, the European (ECMWF), has the heaviest snow stretching from Virginia to Philadelphia to New York. Big snow totals
- The second long-range model, the American (GFS), has the heaviest snow stretching from Tennessee through Delaware. Lower, if any snow totals
- Finally, the National Blend of Models (NBM) has the heaviest snow stretching from Virginia through northern Delaware. Medium snow totals
Timeline for the winter storm
This large winter storm will take shape over the southern plains later this week. It will bring snow and ice across the Deep South, Tennessee Valley and through the mid-Atlantic sometime between late Saturday and Monday evening.
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The best advice is to stay with the NEXT Weather Team for frequent updates, each day to plan and prepare for the weekend. Have the shovels and ice melt ready. This could be the heaviest snow of the season.
Heads up, depending on the timing and track between Saturday night and Monday, there may also be school delays or closings next Monday, Jan. 26.
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