Right Weather Pro

Computer Model Trends: Late weekend storm potential

It is only one computer model run, but, in a pattern this quiet, it is sure to generate some buzz. We’re not trying to turn the crank on the hype machine, and it is still quite possible that this does not come together as some computer models are projecting. You may remember last week there was a computer model run that brought a nasty Nor’easter to the New England coast for early this week. Obviously, that did not pan out. In this pattern, however, that is the kind of scenario we should be watching for. There is a blocky jet stream and slightly  negative NAO. If a storm forms off the Southeast coast, it can get sent up towards the Mid-Atlantic and Northeast.

The weather setup

The ECMWF and Canadian model both take what's left of the Gulf of Mexico disturbance (95L) and kick start it with an upper low moving from the Plains to the Southeast. It hits a roadblock in the Atlantic as it develops off the SE coast, and is forced northwest back to the Mid-Atlantic or SNE shore.
The ECMWF and Canadian model both take what’s left of the Gulf of Mexico disturbance (95L) and kick-start it with an upper low moving from the Plains to the Southeast. It hits a roadblock in the Atlantic as it develops off the SE coast, and is forced northwest back to the Mid-Atlantic or SNE shore.

The models

ECMWF

The ECMWF has the storm getting organized off the SE coast on Thursday
The ECMWF has the storm getting organized off the SE coast on Thursday

ECMWF develops the storm off the coast - probably a sub-tropical or tropical storm
ECMWF develops the storm off the coast – probably a sub-tropical or tropical storm

Ultimately, the ECMWF brings the storm to the Mid-Atlantic or SNE coast. There is support from some ECMWF ensemble members, but more than half do not have a storm impacting SNE.
Ultimately, the ECMWF brings the storm to the Mid-Atlantic or SNE coast late in the weekend. There is support from some ECMWF ensemble members, but more than half do not have a storm impacting SNE.

Canadian

Canadian (CMC) has two storms off the SE coast on Thursday - it makes the second in line the stronger of the two.
Canadian (CMC) has two storms off the SE coast on Thursday – it makes the second in line the stronger of the two.

CMC projects an intense storm off the Carolina coast early in the weekend - possibly a hurricane
CMC projects an intense storm off the Carolina coast early in the weekend – possibly a hurricane

CMC track is farther north than 00Z ECMWF run. Brings a tropical storm to SNE early next week.
CMC track is farther north than 00Z ECMWF run. Brings a tropical storm to SNE early next week.

GFS

GFS has two storms off the SE coast on Thursday - the front runner is the stronger system
GFS has two storms off the SE coast on Thursday – the front-runner is the stronger system

GFS lets the Canadian high pressure dominate in the Northeast while the second storm remains suppressed to the south and in the slow-cooker this weekend
GFS lets the Canadian high pressure dominate in the Northeast while the second storm remains suppressed to the south and in the slow-cooker this weekend

By the time the second storm intensifies and moves north it is far enough east that it misses the Eastern Seaboard by a large margin
By the time the second storm intensifies and moves north it is far enough east that it misses the Eastern Seaboard by a large margin

Bottom-line

It is still very early in the game. One run is one run, and it’s possible this is all for naught if the ECMWF and the Canadian are not handling the pattern correctly. Having said that, it’s a pattern that bears very close watching because of the strong blocking in place. We will be eagerly anticipating the next batch of computer model runs Tuesday afternoon.

For anyone that is thinking that this could be a Sandy sequel, there are some pretty big differences. First and foremost, Sandy was a mature tropical system in the Bahamas that grew into an extremely large and intense storm over the course of a week before reaching the United States. This storm is not forecast to be as large or intense as Sandy was, and it will not have as much time to strengthen. The final track of the ECMWF storm is similar to Sandy, but it is nowhere near as intense.

Fred Campagna

President and Chief Meteorologist - Right Weather LLC AMS Certified Consulting Meteorologist #756 AMS Certified Broadcast Meteorologist #126

Related Articles

Back to top button