Clipper Snowfall

Still looking at a volatile and challenging system for the Northeast tomorrow and Saturday. My first and final accumulation map is below:

Snowfall Forecast: Thursday Night-Saturday Evening (Click to enlarge)

There could still be some significant variability in the snow totals, especially in the area bounded by Syracuse-Albany-Worcester-Hartford-Newburgh, NY. Snow will move in tomorrow morning. From about Trenton, NJ south this looks to be a very low impact event. There may be a brief period of heavier snow to cause some havoc on roadways, but accumulation will be limited. The main area of impact for this storm should be the Catskills, Mohawk Valley, Adirondacks, Berkshires, Litchfield Hills, and perhaps parts of SW Connecticut and Long Island. The main event will wind down Friday evening, but lake enhancement will begin to deliver heavier snow to parts of Upstate NY through Saturday night, leading to the chance of higher amounts there. The Norlun trough effect could take over in Maine and southern New Hampshire Saturday night, leading to higher totals than advertised above (remember this map ends Saturday 7 PM). Max amounts could top off around 12″, with a few higher amounts, primarily in the mountains/upslope of Upstate NY courtesy of lake enhancement or pure lake effect.

Models continue to show a favorable pattern for a large storm for midweek next week. More on that after this system passes.

Select snow amounts through Saturday evening:

DC/Baltimore, MD: Trace
Philadelphia, PA: Coating-1″
Trenton, NJ: Coating-2″
New York City: 1-2″ average
Morristown, NJ: 1-3″
Bridgeport, CT: 2-5″
Syracuse, NY: 3-6″
Utica, NY: 4-8″
Albany, NY: 3-7″
Hartford, CT: 2-5″
Boston, MA: 1-3″


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First Significant Storm in the East Coming?

Last Night's Initialized Euro 500 mb and Surface Map (what's happening "now") - All model images from Allan Huffman's Model Site:

Well, after that lengthy post-Thanksgiving post, I got slammed with flu-like symptoms. So no posting since last week. But, now we’re on the up and up, and the weather looks interesting to say the least.

Let’s start with what’s up right now. We’ve had an interesting couple days with an awfully far south traveling clipper system bringing snow from the Midwest into parts of the Southeast. If you look at the map to the left, it shows what was happening last night, as initialized by the European model. The bulging green/yellow colors on the right indicate  a “block” in the atmosphere centered near and over Greenland (-NAO). As a result, we’re seeing colder air drain out of the higher latitudes on the western side of the block (and, if you’ve heard a bit about cold in Europe, the eastern side too). This is a similar scenario to what was seen  for much of last winter. We appear to be in a long-term phase of this North Atlantic Oscilliation (NAO) being more negative.

84 Hour NAM Snowfall Projection for Maine/Quebec - From Earl Barker's Model Site:

So we’ve got the cold hanging in. We’ve had some snow. Now that one clipper system is going to arc back inland over southeast Canada and deliver some nasty weather to northern Maine and Quebec, and you can see “projected” snow totals from the NAM model to the right (Earl Barker’s model website for the original graphic…great site to bookmark). That be a lot of snow if it materializes, which it should.

Friday Morning's European Model Map (

Beyond this point, things get interesting. The first fly in the ointment comes Thursday night through Saturday morning, as another Alberta Clipper system drives across the Lakes. You can see that at left. Based on my past experience, this right now appears to be a 1-3″ or 2-4″ type of snowfall for areas north of I-80, with higher amounts possible in the mountains and on the coast of New England. Obviously, we’re still a good five days out, so that’s just a VERY rough guess. For what it’s worth, the GFS model also shows this. So far so good.

Now it gets real interesting next week:

European Model Map for Next Monday Morning (
Next Sunday Evening GFS Model Forecast Map (

So here we go…the top image is the European model’s forecast from this morning for next Monday morning. It shows a strong low pressure system over Upstate NY, dropping heavy snow in the Lakes and likely a cold, miserable rain to the Big Cities. However, the GFS model to the bottom image, shows the low off the coast. This implies (and if you translate it out further) heavy snow possibly from I-95 East to the coast, especially as you get into Southern New England. Now, this is over a week away, we still have light years (in meteorological terms) to go until we reach any sort of confidence in the forecast, but there’s a decent signal right now showing up that suggests a significant storm is going to form somewhere in the East within about 10 days, and it could deliver the first decent snows of the winter to some areas. Stay tuned!