2022 Global Model Runs Discussion (Out thru day 16)

[Kingarabian]

There are arguable cases in the past where AEWs splash down as formed TCs. They usually get a red circle, then are classified a TD a day later.

I know there are strong waves which can splash down and immediately transition to a TC but a TC over land? Do you have any examples of this, am really curious about this.

Also FWIW i asked Andy about this a few days back and he was the one who suggested that the ECMWF has a overdeepening bias inland.

https://twitter.com/andyhazelton/status/1555879509878095872?s=21&t=PYBO-860uuxZL6cJRn5bYA


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According to HURDAT data (visualizer search result here):
- Unnamed TD, 1971: TD inside Africa, peaked as TD
- Christine, 1973: TD inside Africa, peaked as TS
- Unnamed TD, 1978: TD inside Africa, peaked as TD
- Unnamed TD, 1978: TD inside Africa, peaked as TD
Most of them only have one advisory cycle inland, and their second data point is already over water.

IMO, the TDs over land may be suspect, and with today's technology they might not have been classified as such while still over Africa. I also think some of these TDs with long tracks typical of CV storms have probably reached TS strength at some point, even just briefly.

A poster said in the 2021 models thread that Donna 1960 may have been a storm before exiting Africa, but HURDAT still has Donna forming over water officially:

When has a tropical system formed hundreds of miles inland with no water underneath?

Please...redpill me.

There was evidence that Donna, in 1960 was already a storm before exiting Africa.

There are many examples of storms that were classified as TDs very close to the African coast. Most recent examples include Rene 2020, Helene 2018 and Florence 2018.

That's my point here, so the EPS solutions while they look off at times in regards to AEWs, aren't impossible.

Basically if the EPS is showing a, inland edge of Africa TC, it means the wave could have a large envelope and is very convectivly active with an evident MLC.

[skyline385]

I know there are strong waves which can splash down and immediately transition to a TC but a TC over land? Do you have any examples of this, am really curious about this.

Also FWIW i asked Andy about this a few days back and he was the one who suggested that the ECMWF has a overdeepening bias inland.

https://twitter.com/andyhazelton/status/1555879509878095872?s=21&t=PYBO-860uuxZL6cJRn5bYA


Sent from my iPhone using Tapatalk

According to HURDAT data (visualizer search result here):
- Unnamed TD, 1971: TD inside Africa, peaked as TD
- Christine, 1973: TD inside Africa, peaked as TS
- Unnamed TD, 1978: TD inside Africa, peaked as TD
- Unnamed TD, 1978: TD inside Africa, peaked as TD
Most of them only have one advisory cycle inland, and their second data point is already over water.

IMO, the TDs over land may be suspect, and with today's technology they might not have been classified as such while still over Africa. I also think some of these TDs with long tracks typical of CV storms have probably reached TS strength at some point, even just briefly.

A poster said in the 2021 models thread that Donna 1960 may have been a storm before exiting Africa, but HURDAT still has Donna forming over water officially:

There was evidence that Donna, in 1960 was already a storm before exiting Africa.

There are many examples of storms that were classified as TDs very close to the African coast. Most recent examples include Rene 2020, Helene 2018 and Florence 2018.

That's my point here, so the EPS solutions while they look off at times in regards to AEWs, aren't impossible.

Basically if the EPS is showing a, inland edge of Africa TC, it means the wave could have a large envelope and is very convectivly active with an evident MLC.

The problem is that the EPS has them at TS strength in the middle of Africa not near the coastline lol. So i have to agree with Andy that there is most definitely an overdeepening bias in the EPS when inland.




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[Kingarabian]

According to HURDAT data (visualizer search result here):
- Unnamed TD, 1971: TD inside Africa, peaked as TD
- Christine, 1973: TD inside Africa, peaked as TS
- Unnamed TD, 1978: TD inside Africa, peaked as TD
- Unnamed TD, 1978: TD inside Africa, peaked as TD
Most of them only have one advisory cycle inland, and their second data point is already over water.

IMO, the TDs over land may be suspect, and with today's technology they might not have been classified as such while still over Africa. I also think some of these TDs with long tracks typical of CV storms have probably reached TS strength at some point, even just briefly.

A poster said in the 2021 models thread that Donna 1960 may have been a storm before exiting Africa, but HURDAT still has Donna forming over water officially:


There are many examples of storms that were classified as TDs very close to the African coast. Most recent examples include Rene 2020, Helene 2018 and Florence 2018.

That's my point here, so the EPS solutions while they look off at times in regards to AEWs, aren't impossible.

Basically if the EPS is showing a, inland edge of Africa TC, it means the wave could have a large envelope and is very convectivly active with an evident MLC.

The problem is that the EPS has them at TS strength in the middle of Africa not near the coastline lol. So i have to agree with Andy that there is most definitely an overdeepening bias in the EPS when inland.

https://uploads.tapatalk-cdn.com/20220816/d5bbe991c7b2eaac5ebb14733b3317e7.jpg


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Yeah I agree but IMO it's just a weird thing the model does when it wants to show a wave will likely have a good shot at developing.

[SFLcane]

06z GFS operational perhaps has one or two TDs in the WCar/GOM, but the main action is in the MDR with the first system starting to form at +114 hours. Eventually becomes a MH (looks OTS in this specific run). Behind it are two new TCs in the MDR. Until we actually have a defined source or already a TC, the ensembles are probably more valuable than single operational runs though.

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

https://i.imgur.com/Swn4yOp.png

Just to clarify for those who may not be following closely, this is the same wave that the GFS from 5 runs earlier (0Z of 8/15/22) had as a hurricane hitting the Leewards on 8/29-30. Energy/moisture that comes off Africa to lead to this developing is per this run convection that is currently already centered over SW Mali near 7W, 12N, and already starts emerging from Africa tomorrow evening near 12N just as it did on yesterday's 0Z run. Because operational runs generally have little reliability going too far out in time, I think it is important to note how soon the seed from this potential trouble hits water and how far west it already is in Africa so that it can be followed closely. I'll try to see if I can see it on satellite.

I mean this is the wave the GEFS is developing.

[skyline385]

That's my point here, so the EPS solutions while they look off at times in regards to AEWs, aren't impossible.

Basically if the EPS is showing a, inland edge of Africa TC, it means the wave could have a large envelope and is very convectivly active with an evident MLC.

The problem is that the EPS has them at TS strength in the middle of Africa not near the coastline lol. So i have to agree with Andy that there is most definitely an overdeepening bias in the EPS when inland.

https://uploads.tapatalk-cdn.com/20220816/d5bbe991c7b2eaac5ebb14733b3317e7.jpg


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Yeah I agree but IMO it's just a weird thing the model does when it wants to show a wave will likely have a good shot at developing.

Agree on that, it’s probably a decent indicator of an incoming strong AEW.


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[toad strangler]

06z GFS operational perhaps has one or two TDs in the WCar/GOM, but the main action is in the MDR with the first system starting to form at +114 hours. Eventually becomes a MH (looks OTS in this specific run). Behind it are two new TCs in the MDR. Until we actually have a defined source or already a TC, the ensembles are probably more valuable than single operational runs though.

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

https://i.imgur.com/Swn4yOp.png

Just to clarify for those who may not be following closely, this is the same wave that the GFS from 5 runs earlier (0Z of 8/15/22) had as a hurricane hitting the Leewards on 8/29-30. Energy/moisture that comes off Africa to lead to this developing is per this run convection that is currently already centered over SW Mali near 7W, 12N, and already starts emerging from Africa tomorrow evening near 12N just as it did on yesterday's 0Z run. Because operational runs generally have little reliability going too far out in time, I think it is important to note how soon the seed from this potential trouble hits water and how far west it already is in Africa so that it can be followed closely. I'll try to see if I can see it on satellite.

I mean this is the wave the GEFS is developing.

https://i.postimg.cc/VN3L0g0k/gefs.gif

Switch flipper

[Spacecoast]

Hour 66: Some shear south of AEW splashdown..

[Kingarabian]

CMC has another BOC system in about 8-10 days.

[lsuhurricane]

CMC has another BOC system in about 8-10 days.

Was just about to say this. 12z GFS also has a system there in 8-10 days. That's a very dubious spot for many reasons at this time of year without the death ridge pushing it towards MX.

And as you'd expect, this system finds life in the GOM and strengthens. Believe both GEFS and GEPS have been knocking on this door for a few days now.

[skyline385]

There’s the NOLA system for August lol




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[SFLcane]

Bunch of weak slop systems on the gfs. Snooze fest..

[SoupBone]

CMC has another BOC system in about 8-10 days.

Is there a hint of this system out there right now?

[SoupBone]

Bunch of weak slop systems on the gfs. Snooze fest..

I sure wouldn't want to be on the end of that GFS run, at the end of August. You know how quickly sloppy goes to Defcon 1.

[NDG]

Indeed the GFS shows yet another possible tropical disturbance heading into the GOM from the south central Caribbean two weekends from now with fairly good UL conditions.
Some Euro ensembles also pointing in that direction.

[SFLcane]

Lots of wavebreaking and dry air issues. Party like it's 2013

[LarryWx]

06z GFS operational perhaps has one or two TDs in the WCar/GOM, but the main action is in the MDR with the first system starting to form at +114 hours. Eventually becomes a MH (looks OTS in this specific run). Behind it are two new TCs in the MDR. Until we actually have a defined source or already a TC, the ensembles are probably more valuable than single operational runs though.

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

https://i.imgur.com/Swn4yOp.png

Just to clarify for those who may not be following closely, this is the same wave that the GFS from 5 runs earlier (0Z of 8/15/22) had as a hurricane hitting the Leewards on 8/29-30. Energy/moisture that comes off Africa to lead to this developing is per this run convection that is currently already centered over SW Mali near 7W, 12N, and already starts emerging from Africa tomorrow evening near 12N just as it did on yesterday's 0Z run. Because operational runs generally have little reliability going too far out in time, I think it is important to note how soon the seed from this potential trouble hits water and how far west it already is in Africa so that it can be followed closely. I'll try to see if I can see it on satellite.

I mean this is the wave the GEFS is developing.

https://i.postimg.cc/VN3L0g0k/gefs.gif

And once again it gets far west in the basin on the 12Z GFS albeit as only a weak sfc low on this run (unlike the western basin MH on the prior run), which is just NE of the Leewards on August 28th:


So, of the last 7 GFS runs, 2 produced Hs and the other 5 runs are weak.

[SFLcane]

Would be hilarious to go all of August without a hurricane. Starting to think it might happen

[aspen]

The GFS has finally entered the phase where it’s recognizing favorable conditions and multiple possible areas of genesis in the mid to long range, but has zero consistency as to which one(s) could develop. I’m leaning towards no development for the wave in the 06z run that emerges this weekend; it could act as a sacrificial wave to clear out some SAL for the waves behind it in very late August.

[NotSparta]

Lots of wavebreaking and dry air issues. Party like it's 2013

2013 and wavebreaking in the same post, that's two shots folks

[toad strangler]

Bunch of weak slop systems on the gfs. Snooze fest..

good luck with a wave washing out on 8/31 just N of the GA's. I don't believe that for a second. I love the entertainment 300 plus hour maps bring