2020 Global Model Runs Discussion (Out thru day 16)

[GCANE]

so gfs want be active models of season it told us about Cristobal now want show some thing in sw carribbean

First one to ID Arthur as well.

[aspen]

:uarrow: Remains weak. It's likely we'll see a disturbance or two emerge from the WCaribb. That's a stark difference from prior years as its been a graveyard for TC's for most of the past decade.

Given the OHC in the WCAB, that is concerning

If this AEW/potential system were to get itself together, track through the western Caribbean’s high OHC pocket, and find itself in an area similarly favorable to Cristobal before its first landfall, I think it would have a good chance of becoming the first hurricane of the year. That’s if it is able to develop, though.

[StruThiO]

 https://twitter.com/webberweather/status/1270053976961138688




 https://twitter.com/webberweather/status/1270055565142765569




 https://twitter.com/webberweather/status/1270056497943281669

[GCANE]

As far as Earth Nullschool takes this out, i.e. 6/13

it shows an AEW at 47W.

One AWB NE of Hawaii, another over a good portion of Mexico.
The Hawaii one is the one currently east of Japan.
The AWB over Mexico will likely interact with AEW in the west Carib.
The AWB NE of Hawaii will likely be the one interacting with the MDR AEW later.

[Kingarabian]

12z Euro is on board showing a disturbance (disturbances?) emerging from the WCaribb.


One thing models seems to be unanimously agreeing is the steering, in that it will likely be lifted north no matter the strength of the disturbance.

[Aric Dunn]

Situations like this typically have high chances of development. large areas of convection in the western carrib the fester for days.. I mean how many times have we seen the GFS sniff these things out.. just ot have the Euro jump on later.

GFS typically fails in overall track forecasting but it shure is good at sniffing out long range condusive set ups..

and the fact that, even though weak, the euro does show something.

[northjaxpro]

Situations like this typically have high chances of development. large areas of convection in the western carrib the fester for days.. I mean how many times have we seen the GFS sniff these things out.. just ot have the Euro jump on later.

GFS typically fails in overall track forecasting but it shure is good at sniffing out long range condusive set ups..

and the fact that, even though weak, the euro does show something.

So many folks tend to lose sight on how well the GFS has performed through the years, in not only sniffing out early season development from large CA gyres, but a decent job modeling early season tropical cyclones , especially when they emerge into the Gulf of Mexico or off the Southeast U.S. Atlantic Coast. The GFS continues to do this very well, as we have clearly seen with this season's named storms. This time of the year, I usually rely on what the GFS indicates in my analysis in monitoring the tropics, especially in the Carinbean and the GOM.. Generally most times, the EURO eventually most of the time falls in line with it as the end result from those regions of the basin!

[Blinhart]

As far as Earth Nullschool takes this out, i.e. 6/13

it shows an AEW at 47W.

One AWB NE of Hawaii, another over a good portion of Mexico.
The Hawaii one is the one currently east of Japan.
The AWB over Mexico will likely interact with AEW in the west Carib.
The AWB NE of Hawaii will likely be the one interacting with the MDR AEW later.


https://i.imgur.com/6iV3E0t.png

https://i.imgur.com/VjMKnTH.png

https://i.imgur.com/iQbMDXX.png

I've never seen these and completely confused

[Kingarabian]

18z GFS trending stronger despite more land interaction:

[Kingarabian]

Hanging around north of the Honduras due to weak steering currents:

[Kingarabian]

Well I take back my previous comment lol about the lack of ridging agreement. GFS crashes this into CA on this run.

[aspen]

Even though this run takes the system into CA, the GFS has been predicting a decent TC within the 10-day time framed and the precursor could form as early as this Sunday.

[Kingarabian]

Even though this run takes the system into CA, the GFS has been predicting a decent TC within the 10-day time framed and the precursor could form as early as this Sunday.

Yeah for sure it's going to be a lot of model watching on this one.

[GCANE]

As far as Earth Nullschool takes this out, i.e. 6/13

it shows an AEW at 47W.

One AWB NE of Hawaii, another over a good portion of Mexico.
The Hawaii one is the one currently east of Japan.
The AWB over Mexico will likely interact with AEW in the west Carib.
The AWB NE of Hawaii will likely be the one interacting with the MDR AEW later.


https://i.imgur.com/6iV3E0t.png

https://i.imgur.com/VjMKnTH.png

https://i.imgur.com/iQbMDXX.png

I've never seen these and completely confused

First one is a tropical wave (AEW). This is at the 700mb level. Notice the kink in the winds.
Tropical waves move from east to west.

Next two are at 250 mb.
The trofs are Rossby waves, commonly called the Jet stream.
East of the bottom of the trofs are anticyclones.
An anticyclone associated with the Rossby wave trof is called an Anticyclone Wave Break (AWB).
Rossby waves move from west to east.

When an anticyclone gets over a tropical wave, or other forms of low-level vorticity, chance for tropical-cyclone genesis increases.

[GCANE]

00Z GFS shows interaction at 144 hrs.
The AWB appears not as vigorous and hence no development.
Waiting to see what 06Z run shows.

[GCANE]

The anticyclone sets up really well at 156hrs in the Carib.
However the wave is moving faster and is offshore of Honduras.
The wave needs to slow down for this to work or the anticyclone needs to setup faster.

[floridasun78]

we may not see any thing nw carribbean some time gfs over do it time will tell (( i look at last gfs 06z run it dont any thing in nw carribbean next weekend))

[GCANE]

Coming back on the 12Z run

[Hurricaneman]

The one thing we can take from the gfs and Euro is a robust wave train which is only going to get more robust as we move on in time

[Kingarabian]

Not much from the 12z suite. Models now favoring the EPAC for near future development.