Good morning. This storm has been a lot of fun to track and will be extremely challenging. There is a balancing act that needs to be down between an extremely powerful storm and a sharp cutoff in snowfall. The idea that the European model was too far west seems to be working out as there was a shift east in most modeling yesterday. However, that does not mean a low impact storm. It just means snowfall will not make it well inland. I will explain below.
Here is my updated forecast map. There will be one more final update tomorrow morning
As you can see I am still favoring eastern New England for big impacts with notable impacts along coastal NJ into central CT, Mass, Maine. I tried to nail down where I think the sharp cutoff will be. The tricky part about this forecast is a 15 mile shift makes a massive difference. I tried to estimate where this will settle out and this map does not reflect any particular model run.
Here's a summary:
- Overall this is a major storm for many areas along the coasts
- As always (hate saying this but I need to), things can change and there is still the chance the storm just makes a glancing blow
- Snow approaches the area Friday evening. For most, this is after the rush hour outside southern areas
- I want to note there is a small disturbance on the arctic cold front that could cause some light snow in areas like NNJ on Friday afternoon so be on the lookout
- By late Friday night into the early morning the storm really cranks up for areas in the Delmarva and coastal NJ.
- At this time we will see how far west these snow bands get into interior NJ
- By day break the storm is continuing to strengthen and all areas are seeing accumulating snowfall
- By Saturday afternoon the storm starts to pivot over eastern New England causing signifigant snow accumulations and snowfall rates 1-3" per hour.
- At this time we will need to evaluate how much of this heavy snow falls back onto areas like NYC eastern NJ etc
- Storm tapers off by Saturday night for most
The GFS is east of this, likely too far. This model sometimes has issues jumping storm energy too far off the coast. Just as the European yesterday had the error of bring the storm too close, GFS has the opposite problem...
Notice how much more east the GFS is and how its just a glancing blow for many. Can this happen? Of course but this where we need to use forecasting techniques to make a prediction.
This whole storm comes down to how fast upper level energy pivots around the trough and how quickly the trough goes negative...
Based on this, is where the upper level low will form and how close to the coast it gets. Heavy snow will fall just to the north and west of upper low....
In any event, I do not see a scenario where eastern New England escapes this. The areas that can be spared are NJ and interior New England if GFS is correct.
Along the coasts there will be high surf and wind from this storm. The low is expected to "bomb" out which means it rapidly deepens. When this occurs the winds pick up along with the tides.
Stay tuned more updates to come.
Hey Willie, imagine if the NAO had been negative, had there been a blocking high off the coast of Newfoundland -- this one might have bombed out near us and we'd be shoveling into February! Very tricky situation at the bottom of that trough, but maybe the Euro is gonna ace it once again. Canada models this AM looking at a strong and quickly forming storm on a coast-grazing track, GFS sees a weak diffuse storm out to sea, Euro coming in between (NAM too, more or less, while HRRR sides with GFS). Kind of unusual and interesting for this much divergence at 48 hours out. Jim G, still here.
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