2020 Global Model Runs Discussion (Out thru day 16)

[northjaxpro]

Per the GFS and Euro, there might be a chance that something briefly comes off the Panhandle and attempts to form as it ejects ENE.

Here's tonight's 00z Euro closing it off @ 1009mb:
https://i.imgur.com/DKPWGEF.png

The last 3 runs of the GFS, including this morning's 06Z run, have been consistent in showing a potent vorticity max droppng south from the Tennessee River Valley to the coast of the Florida Panhandle by Sunday (July 5). GFS closes off a 1008 Low Pressure near Apalachicola and slowly moves it across North Florida, and then moves it just off the SE U.S. Coast by next Tuesday (July 7).

So, we have agreement and model support with GFS and EURO of potential of seeing some development across the region from Apalachee Bay to off the Southeast U.S. coast.

So, this is worthy of a seperate thread discussion!

[ronjon]

So far GFS is the only model developing low pressure in the northern GOM. Let's see if other globals jump on board.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=us&pkg=mslp_pcpn_frzn&runtime=2020062906&fh=174

[northjaxpro]

00Z Canadian picks up that vorticity max dropping south toward the Gulf Coast with 1010 mb Low Pressure into South Alabama by 18Z Sunday.

So, CMC is on the GFS heels so to speak. Just keep folowing the future runs ....

[NDG]

So far GFS is the only model developing low pressure in the northern GOM. Let's see if other globals jump on board.

https://www.tropicaltidbits.com/analysis/models/?model=gfs&region=us&pkg=mslp_pcpn_frzn&runtime=2020062906&fh=174

The Euro also agrees with the set up over all but has disturbance inland over NE FL before moving offshore of S.C. and then somewhat intensifying.

[northjaxpro]

Right. There could be a severe weather potential across North and Northeast Florida next Monday as the potential Low Pressure area crosses this reigon. I am already beginning to take notice of this.

But, yes NDG, both the GFS and EURO really pull the system together just off the SE. U.S. coast on July 7.

[TheStormExpert]

Well I’m keeping my fingers crossed that whatever this is kicks itself out into the Atlantic sooner rather later as I’m hopefully heading up to Gainesville next Sunday through Wednesday.

[northjaxpro]

12Z GFS still showing 1011mb Low Pressure forming in Apalachee Bay (4th run in a row), emergizes off Mobile Bay actually late Friday and drifts slowly eastward to just south of Panama City by this upcoming Sunday. It intensifies the cyclone to 1007 mb before landfall near Dixie County in the Big Bend regon by 16Z Sunday morning.

A very wet period in store for North and Northeast Florida and portions of the Northeast Gulf Coast region going into the upcoming weekend.

[MGC]

From Monday morning LIX AFD:

.LONG TERM...The mid and upper level ridge axis will shift to the
west on Thursday as a strong upper level trough digs into the
eastern third of the nation. A deep layer northerly flow regime
will set up across the region and remain in place through Sunday.
Both the GFS and the ECMWF indicate that a strong vort lobe will
slide down from the Ohio Valley Thursday into Thursday night. An
MCS is expected to accompany this vigorous upper level feature,
and have increased POP of 40 to 60 percent in the forecast during
this period. This MCS could bring strong to severe storms with
damaging wind gusts to the area late Thursday into Thursday night.
Temperatures will warm into the middle 90s Thursday afternoon in
advance of this system as a weak downslope component allows for
some compressional heating to occur.

Could we witness another Barry type system similar to last July?....MGC

[TheProfessor]

From Monday morning LIX AFD:

.LONG TERM...The mid and upper level ridge axis will shift to the
west on Thursday as a strong upper level trough digs into the
eastern third of the nation. A deep layer northerly flow regime
will set up across the region and remain in place through Sunday.
Both the GFS and the ECMWF indicate that a strong vort lobe will
slide down from the Ohio Valley Thursday into Thursday night. An
MCS is expected to accompany this vigorous upper level feature,
and have increased POP of 40 to 60 percent in the forecast during
this period. This MCS could bring strong to severe storms with
damaging wind gusts to the area late Thursday into Thursday night.
Temperatures will warm into the middle 90s Thursday afternoon in
advance of this system as a weak downslope component allows for
some compressional heating to occur.

Could we witness another Barry type system similar to last July?....MGC

I was thinking something Barry like, however with an eastward movement like the GFS shows instead of a westward movement it wouldn't get as much time over water as Barry did.

[TheProfessor]

The 18z GFS doesn't push the energy as far south, thus it doesn't strengthen as much as the 12z. It does however park the energy over Georgia, which is concerning. Not only could that lead to a flooding issue, but if it's a sign of very little steering currents occurring and you possibly get a storm slowly moving either in the Gulf or Atlantic, then there could be a significant increase in impacts.

[Kingarabian]

The 18z GFS doesn't push the energy as far south, thus it doesn't strengthen as much as the 12z. It does however park the energy over Georgia, which is concerning. Not only could that lead to a flooding issue, but if it's a sign of very little steering currents occurring and you possibly get a storm slowly moving either in the Gulf or Atlantic, then there could be a significant increase in impacts.

Yeah. Eventually pushes it off ENE where it eventually ends up over waters and slowly deepens.

[northjaxpro]

5th run in a row by the GFS showing development in Apalachee Bay by 12Z Saturday morning. 18Z GFS shows it developing and re-emerging just off shore the Georgia coast by 12Z next Monday at 1007 mb.

18Z ICON also has a weaker 1013mb Low Pressure in Apalachee Bay late Saturday.

Time for separate thread on this potential development. There is sufficient model support for it now.

[TheProfessor]

The 0z Canadian trended stronger and a bit east with the 850mb vorticity compared to the 12z Run. Although it doesn't make it off shore, it drops a ton of rain in Mississippi, Alabama and Louisiana.


The 0z GFS is a little further east but west of it's 12z run and parks the low level energy over Alabama.


Right now the models are keeping this energy just off the coast. This will need to be watched closely as we could see a Barry-esque situation where the energy moves into the Gulf and strengthens into a storm. There have been previous model runs that have shown this and with quite a bit of variance for something that's still 3-7 days out, it can't be ruled out. Of course we all know it doesn't take a named storm to cause devastation. All it takes is a slow moving system to take advantage of the warm waters of the Gulf and dump rain.

[Ubuntwo]

The 0z Canadian trended stronger and a bit east with the 850mb vorticity compared to the 12z Run. Although it doesn't make it off shore, it drops a ton of rain in Mississippi, Alabama and Louisiana.
https://i.imgur.com/sQ1QjzA.gif

The 0z GFS is a little further east but west of it's 12z run and parks the low level energy over Alabama.
https://i.imgur.com/9jKChz5.gif

Right now the models are keeping this energy just off the coast. This will need to be watched closely as we could see a Barry-esque situation where the energy moves into the Gulf and strengthens into a storm. There have been previous model runs that have shown this and with quite a bit of variance for something that's still 3-7 days out, it can't be ruled out. Of course we all know it doesn't take a named storm to cause devastation. All it takes is a slow moving system to take advantage of the warm waters of the Gulf and dump rain.

Many runs have had this continue east after stalling, emerging off the EC with another window for development.

[Kingarabian]

00z Euro:

[northjaxpro]

We will have a very slow moving system which will meander either right on the coast of the Florida Panhandle or get just south of the area into Apalachee Bay beginning Friday and continuing right through Monday.

At the very least, it will be a potential heavy rain maker across the Northeast Gulf of Mexico during this holiday weekend as this system moves very slowly. GFS runs for the most part have had the system drift just off the coast of the Florida Panhandle and drift slowly east , with pressures generally in the 1009 mb to 1011.mb range. Thereafter, GFS moved the energy across North Florida and South Georgia during Monday, and then that is where the GFS and the other models diverge thereafter.


Most earlier runs of the GFS and EURO had the system emerging just off shore the Southeast U.S. Atlantic Coast beginning Monday July 7, and possibly slowly intensifying, while the Canadian and ICON model runs over the system inland over Georgia by Monday instead of moving off shore the Southeast U.S Coast..

However, the 00Z GFS and EURO for this run cycle have backed off the system emerging.off the Southeast U.S. coast by Monday as well. Each model moves the vorticity inland, with the GFS lagging the vorticity over South AL and over South GA Sunday, and then move it northeast, delaying moving the system off the Souiheast U.S. Coast until either on July 9.or July 10. This system will be very interesting to monitor and it is one that will really vary day by day. It definitely will be a very slow mover and the rain potential could be very significant across the Northeast Gulf region and North Florida area this weekend into early next week.

[cycloneye]

 https://twitter.com/BigJoeBastardi/status/1277964227248963584

[TheProfessor]

The 6z GFS does send some energy off the Mississippi/Alabama coast, but it quickly moves eastward/east-northeastward back on shore.

[aspen]

12 GFS is significantly more aggressive with the SE coast system, having a pretty substantial TS by the 150-170 hour range. It starts forming as early as 114 hours.

The next EPac system also starts forming as early as the end of the week, and doesn’t get very strong.

[northjaxpro]

A quick glance at the 12Z GFS

The 850 mb vorticity never makes it into Apalachee Bay this run.

GFS has moved up the time frame with the development of the system this run compared to the previous ones.
850 mb vorticity never makes it into Apalachee Bay this run .
It keeps the vorticity strung out across South AL Friday and into Saturday and later into South GA.

However, the vorticity consolidates as it drifts to near the Northeast Florida /Southeast Georgia region by Sunday. GFS shoesa 1006 mb potential cyclone developing just off the Georgia coast by 12Z Sunday morning.

I will check out and analyze the other 12Z model runs a bit later ..