December 1, 2020 – A very active month in the East as a series of storms will be moving through about every 3-5 days. December will go down in some places as a snowy month. Now understand, the snows will occur for at least the first 3 weeks of the month then I think after the 24th, winter backs off for a week and then comes roaring back the beginning of January. The highest frequency of storms will be centered over the Great Lakes, Appalachians and Northeast.
The PNA will remain positive which means a trough in the eastern part of the country. For coastal storm lovers, the NAO will be negative for at least the first tow if not the first 3 weeks of the month. That means the potential is there for snows all the way to the coast. We may see one good storm wind-up along the coast that brings what I term a “Big Daddy” snowstorm.
The one issue that can ruin the entire forecast is the strength of the La Nina. Notice that the La Nina as of Nov 30 is moderate to to strong and that could force the jet and troughs too far east so that storms end up winding-up well off the coast. That certainly is a concern I have.
If you are looking for prolong cold weather, well not going to happen. Snowstorms that do occur will occur with marginal temperatures i.e. 28-34 degrees followed temperatures rebounding back in the 40s and 50s. So snow cover may come and go quickly with each storm. I do think that same pattern will hold in January and may even get more active and colder.
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