2020 Global Model Runs Discussion (Out thru day 16)

[floridasun78]

nws have big rain event here in south fl on sunday to monday as low form in gulf cross south fl

[Gums]

Salute!

Way these wimpy fronts coming thru, doesn't look like a good chance for a low in SW gulf until late Sunday

Good news here ( Panhandle) is cooler nights, but still no rain as we usually see in April and early May.

I still think we'll get a stalled front and weak storm before the end of May. We have seen several in very early June, so I am going with past experience ( 1966 - now).

Gums sends...

[cycloneye]

The new scenario is a crossover from EPAC to Caribbean and Western Atlantic.

[plasticup]

The new scenario is a crossover from EPAC to Caribbean and Western Atlantic.

https://i.imgur.com/nj0jciz.gif

https://i.imgur.com/ajGvtl4.gif

Now that would be something to see. Basin-crossers are rare, and Pacific to Atlantic even more so. I can't find a more recent example than the 1949 Texas hurricane. Anyone know of a more recent case?

[JetFuel_SE]

The new scenario is a crossover from EPAC to Caribbean and Western Atlantic.

https://i.imgur.com/nj0jciz.gif

https://i.imgur.com/ajGvtl4.gif

Now that would be something to see. Basin-crossers are rare, and Pacific to Atlantic even more so. I can't find a more recent example than the 1949 Texas hurricane. Anyone know of a more recent case?

Officially, Tropical Storm Hermine in 2010 formed from the remnants of TD 11-E.

[TheStormExpert]

The new scenario is a crossover from EPAC to Caribbean and Western Atlantic.

https://i.imgur.com/nj0jciz.gif

https://i.imgur.com/ajGvtl4.gif

Now that would be something to see. Basin-crossers are rare, and Pacific to Atlantic even more so. I can't find a more recent example than the 1949 Texas hurricane. Anyone know of a more recent case?

I mean it’s not completely a crossover but the remnants of TS Alma in 2008 in the East Pacific which eventually was retired led to enhancing the development of 2008’s TS Arthur in the western Caribbean along with a tropical wave in late-May.

[cycloneye]

12z GFS is loaded.

1-Crossover from EPAC to Caribbean and West Atlantic.
2-Leftover from disturbance that will move thru South Florida by late Sunday / Monday.
3-NGOM very long range.

[aspen]

12z GFS is loaded.

1-Crossover from EPAC to Caribbean and West Atlantic.
2-Leftover from disturbance that will move thru South Florida by late Sunday / Monday.
3-NGOM very long range.

https://i.imgur.com/cqdhqpV.gif

https://i.imgur.com/bGO8NAu.gif

And it looks like there’s a weak TC trying to form north of the Greater Antilles next weekend.

[JetFuel_SE]

Gotta love long range GFS.

[Ubuntwo]

Gotta love long range GFS.
https://i.gyazo.com/d8b280811fd20a122bc6962225671198.gif

Perfect example of two lows interacting ^

[GCANE]

A front may try and spin up a low-level vort in the Florida Straits about 144hrs out.
GFS is showing it moving into the Bahamas and going slightly warm core.
However, it will be under a strong 355K PV area, so at this point, doesn't look like it will amount to much.
Keeping an eye on it though as the forecast develops over time.

[gatorcane]

12Z GFS going with possibly a subtropical low near east coast of Florida:

[DorkyMcDorkface]

12Z GFS going with possibly a subtropical low near east coast of Florida:

https://i.postimg.cc/SRrR2Nq8/gfs-mslp-wind-seus-27.png

It looks like it does acquires some subtropical characteristics eventually.


The Euro and CMC have nothing, however. While it's not in an entirely outlandish range, I'd still like to see some more consensus before jumping on the development train, especially since it looks like it develops from a rather spurious-looking area of vorticity (convective feedback?)

[TheStormExpert]

12Z GFS going with possibly a subtropical low near east coast of Florida:

https://i.postimg.cc/SRrR2Nq8/gfs-mslp-wind-seus-27.png

It looks like it does acquires some subtropical characteristics eventually.
https://i.ibb.co/X2bkZVn/gfs-mslp-pcpn-eus-fh174-300.gif

The Euro and CMC have nothing, however. While it's not in an entirely outlandish range, I'd still like to see some more consensus before jumping on the development train, especially since it looks like it develops from a rather spurious-looking area of vorticity (convective feedback?)
https://i.ibb.co/2dPTkwv/gfs-z850-vort-eus-fh108-204.gif

If it sits and rides along the Gulf Stream it would acquire Subtropical or even Tropical characteristics. Of course chances of it hovering over the Gulf Stream is like threading a needle.

[GCANE]

Looks a little more tropical on this run.
Its hard to see, though, what's the catalyst for genesis.

[Ubuntwo]

00z ECMWF

[DorkyMcDorkface]

Starting to see a little more agreement between models that some sort of low could form off the SE coast sometime next weekend or early next week. RIght now the GFS has a broader low that doesn't seem to gain any tropical or subtropical characteristics while other models have a more defined system. I'd say it's definitely worth watching to see if the pre-season streak gets extended for one more year.

[TheAustinMan]

With regard to the potential SE US/Bahamas system, we're starting to get into the more reliable range for the deterministic models, but I'd say it's probably wiser to continue prioritizing the ensembles given the high uncertainty at the 5-7 day range. The operational models give a "best guess" of the storm's evolution, but it's important not to get suckered into what it shows since it changes every run, especially in the 5-7 day range. At least with the GEFS suite, it appears that a majority of the guidance starts to develop a low and broad cyclonic rotation in the Bahamas along the tail end of a cold front around Friday. Looks like the European ensembles are starting to lean more into that as well, at least compared to what they had a few days ago. Hard to really take a stab at whether the dynamics favor tropical/subtropical/non-tropical development after that until we get into more of the 2-3 day range, especially since the system may be influenced by upper-air features that haven't even reached the Pacific coast of the U.S. yet.

280 kB. Source: TropicalTidbits

[jconsor]

UKMET looking more interesting - showing the system strengthening just off the SE coast day 6-7 and gradually acquiring more warm core characteristics.

The UKMET tends to have the least false positives for TC genesis of any model,i.e the least tropical cyclones shown in the model forecast than don't verify, whether in the Indian Ocean, Western and Eastern Pacific, or the Atlantic. So when it shows development, I take notice. This is the first UKMET run to show development, but if it remains consistent for a few runs, that would be a strong signal in favor of subtropical/tropical development.

Starting to see a little more agreement between models that some sort of low could form off the SE coast sometime next weekend or early next week. RIght now the GFS has a broader low that doesn't seem to gain any tropical or subtropical characteristics while other models have a more defined system. I'd say it's definitely worth watching to see if the pre-season streak gets extended for one more year.

[CyclonicFury]

 https://twitter.com/pppapin/status/1259626203918372864




The model consensus has my attention. This part of the Atlantic has had several named storms form in recent years during May. Some of the GEFS and EPS members are stronger than the operational. It seems likely that a low of some sort will form under the ridge, but the strength of the low is uncertain and it is unclear whether the low will be non-tropical, tropical, or subtropical. If models continue to show this for a few more days, I'd expect the NHC to give it a STWO mention.