Wednesday, February 3, 2016

Wednesday Morning Storm Outlook: Case Study Storm Now on Most Models

Good morning everyone. Well we have come a long way since I started my case study last Tuesday focusing on the period following the Superbowl. Here is quick summary:

  • Big cold surge moves in over the weekend
  • On the heals of this cold surge a coastal storm can develop Tuesday
  • This is supported by a very large scale ridge of high pressure out west which is causing the jet stream to buckle over the east coast. 
  • Many details have to be ironed out including who gets the hardest impacts if this storm does in fact develop
    • At this time everyone in northern Mid-Atlantic and New England is in play
    • No storm is also still a possibility 
  • More details to come as I continue to break this down

We have gone from pure speculation to now staring down a legitimate storm threat for next week. To review, the image below where my initial thoughts from early last week..

Fast forward to this next image valid for the same time (only much closer range)...

So what does this mean? It means the upper air pattern has trended towards a potential major storm developing early to middle of next week. The key thing to look at in the image above is the strength of the tough in the east seen by the blue and green colors compared to my original image. This shows the strong trend. 

As always we have a spread of model outcomes and we can not nail down specifics yet. However, I have seen enough to start to discuss in more detail.

All models right now are starting to agree with two main elements. The first element is an initial area of low pressure that will drift off to sea on Monday..

There still are some modeling differences with this initial low pressure center and it will cause the overall prediction of next week to be very difficult. However, most guidance does suggest this  stays out to see clearing the way for the main storm. In the wake of this, here is the set up that evolves for the main storm..

Now if, where, and when this storm forms will depend on the features I outlined above. For example, the stronger that ridge of high pressure to the west the greater chance that big trough of low pressure to the east digs more and amplifies. If we start to see that ridge out west trend less amplified, then our projected storm will form more out to sea due to a more progressive pattern and flatter trough. When this trough digs and amplifies it causes a surface low pressure center to form directly to its east as I indiced by the low pressure symbol above. That is our potential storm. So bacially the key to this whole set up is one, how does that lead system behave and two, how amplified does the actual pattern become in its wake.

Models right now at the surface look like this...

Again, depending on how amplified the upper air pattern gets will dictate the actual position of this storm. That means yes, inland areas are in play as well as coastal areas. The image above is just one model projection. To sum this up better, here is a spread of outcomes..

I am showing to drive home the point that there are many possibilities to this storm including no storm at all.

Regardless, it seems my ideas are starting to show some merit here and I will be watching closely how this evolves over the next few days. If I had to make a guess right now I would say this is a storm that develops around the Delaware bay or just over NJ and tracks due north effecting areas just to the west of the I-95 corridor into New England with snow.

I will start cutting nightly videos discussing this threat as it evolves. Stay tuned!


  1. Hmmm, mid-day Euro seems to be flip flopping, a bit less "bullish" than last night about the Tuesday / Wednesday system. Also, it seems to get us out of the Arctic trough by Saturday the 13th, heading back into a ridge! Mid day CMC still sees significant snow, but GFS and GEFS accumulations are meh, 5 or 6 inches, could be partly slush given lower atmosphere temps a bit above 32/0. Not yet seeing the early convergence that happened with "Jonas". NAM will pipe in on Saturday, that should be interesting. If and when the Euro can make up its mind, then maybe we'll have something to talk about.

    PS, interesting article today from the Capital Weather Gang in the Wash Post, as to whether global warming is being reflected in snowfall patterns in the northeast. Points out that a strong majority of the big storms since 1889 have happened in the last 37 years. Interesting quote: "Storms that unload at least 16 inches of snow are now happening every five or six years, nine times as often as they did before 1979 when they only occurred once every 45 to 50 years." At the same time, the trend in total snowfall per season is going down. So, less snow overall but more big storms? This ain't exactly a rigorous scientific study covering the entire planet, but still pretty interesting IMHO. P.S., the "Gang" isn't very bullish on the Tuesday/Wednesday storm just yet. Jim G

    1. So I was looking at a lot of analogs for this potential storm Tuesday. Feb of 1988, Jan of 2001 and to a certain extent the storm of late December 2000 look decent. I think this things forms Jim, the jackpot might be more in New England though. Time will tell!