Thursday, March 17, 2016

Thursday Morning Storm Discussion: My Preliminary Thoughts

Good morning everyone. As I discussed in my video last night we had some pretty big developments yesterday with the evolution of our storm threat for Sunday into early Monday. In particular, models began a westward trend. Over the next few days they still might wobble back and forth, but I am ready to give you guys my first speculation on what I think will happen with this system. Obviously I will have to update this as the days go on. 

Here is a summary:

  • Big late season winter storm effects the east coast Sunday into Early Monday
  • The storm is by no means a lock but Weatherwilly is gaining confidence on this occurring
    • There is still a scenario on the table where this goes out to sea
  • An outbreak of arctic air precedes this storm on Saturday
    • This will aid in supplying the fuel necessary to produce snow for many areas
  • Low pressure then develops in the Gulf of Mexico and tracks northeast as it rapidly intensifies aided by approaching northern jet stream energy
  • For estimates on impacts, I would not be surprised to see this storm trend a little more west
  • This would mean..
    • All areas start off as snow Sunday
    • Mixed precip and some rain develops in areas south and east of interstate 95, especially along coastal areas
    • Areas NW of I-95 up into New England gets the brunt of this system in terms of possible accumulations
Here is a visual representation of my projected impact zone. No accumulation maps yet, but significant accumulations are possible in highest impact zone. 

The map above is my take, not just what the models are spiting out. If the storm shifts away from my ideas I will be adjusting this.

So lets dive in to some updated modeling.

The GFS is still playing games trying to keep this storm just off the coast..

The European, UKMET, and European Ensemble System are all to the west of this. Below is the UKMET model which looks very similar to the European...

I really like the track the UKMET is showing, it makes a lot of sense to me. This model has done an excellent job this winter and usually when blended with the European is a good tool to use. 

So why am I not buying the GFS? Is it because I just want it to snow? Well, I try my best to eliminate that bias but let me show you what I am looking at..

What you are looking at above is energy in the atmosphere at 18k feet. This energy comes together to produce storms. The two circles areas represent the GFS model's prediction of how this energy is handled. Notice how it looks stretched out. This is an error that the GFS tends to make and the result is a storm that is projected to go out to sea due to the energy not consolidating properly. Below is what I think this should look like instead..

Might be hard to tell but in this image that energy is not as sheered out and results in a storm that is closer to the coast. We should start to see the GFS correct west next 2 days. If it does not then that will be a red flag to me that my ideas might be wrong. 

So thats all for this morning. We have a very exciting late season snow threat on the boards and we will get even more helpful data today. 

I will have an update tonight up around 830.

1 comment:

  1. Cool! But still a tricky set up. Euro yesterday was the farthest east solution, now the farthest west and most phased (and most accumulation). I know that the Euro is still the king of the model skills ratings, but it's not always the Rock of Gibraltar. A little farther west on that UKMET run and you have an inland runner. But hey, why not one last hurrah to winter? NAM chimes in later today, the 6z run ends with the low pretty close to the Carolina coast. Could be an interesting way to celebrate the Spring Equinox! Happy St. Patrick's Day. Jim G