2020 Indicators: SST's / SAL / MSLP / Steering / Shear / Instability / Sat Images

[Hammy]

We now have a full fruit basket in the eastern MDR — Invest 91L the orange, soon-to-be 92L the cherry, and a new lemon. It’s very possible we could see Paulette, Rene, and Sally from these waves in the next 7-10 days. Welcome to September!

Gonna get a big ACE boost soon, methinks...

The ACE hand wringers of recent are all about to share the same fate as the early season SST hand wringers and the season long SAL hand wringers. #FAIL

I will say given I've been pitching the CFS since May I should've put more faith into it as it's been showing somewhere between September 8-12 as the start of the big ACE pumping storms since mid to late July.

[SFLcane]

I just posted in the models thread the new EPS it has a VERY intense Signal near the Bahamas for TW that will be coming off Africa in 4-5 days. Something to watch

[Kingarabian]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

[TheStormExpert]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

Rising air over Africa and the Indian Ocean with the standing wave and sinking air over the Atlantic like the graphic shows is favorable I thought? I remember asking this before.

[CyclonicFury]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

Also the return of upward motion to the Atlantic in mid-October suggests we may see an enhanced risk of TC genesis in the Caribbean then.

[aspen]

I’m starting to think 2020 could break another record over the next few weeks: the most amount of named storms in September. We’ve already had two (Nana and Omar), and the models are showing 3-5 more through the middle of the month. That’ll be 5-7 named storms in the first two weeks of September. If the models are that aggressive with development after missing half of the storms this year, I can easily see the Atlantic pumping out 8-10 this month, matching or breaking the record for September activity. We’ll also likely have quantity and quality, with pretty good model consensus for 1-3 long tracking hurricanes in the next 10-14 days that will send 2020’s ACE total skyrocketing.

There’s a decent chance we could end September with Alpha or Beta, >8 total hurricanes, >4 majors, and >120 ACE.

[weeniepatrol]

On today's episode of 2020ing, we have raw, strong westerlies from 50W to Africa south of 12N

[Kingarabian]

On today's episode of 2020ing, we have raw, strong westerlies from 50W to Africa south of 12N

https://imgur.com/kSWWStv

This can happen in active hurricane seasons. Seen it in 2017. However this prolonged event of considerably weak easterlies in the MDR is becoming noteworthy.

[TheProfessor]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

A favorable background state occurring in October over the Caribbean is certainly concerning for CAG season.

[ColdMiser123]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

That kind of velocity potential configuration with rising motion over Africa and the Indian Ocean correlates well to what we've seen in historically active Atlantic hurricane seasons.

[NDG]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

Rising air over Africa and the Indian Ocean with the standing wave and sinking air over the Atlantic like the graphic shows is favorable I thought? I remember asking this before.

Yes, that is what he meant to say, that the VP200 graphics can be misleading.
What to take out of from active years is that the heart of the sinking air is over in the EPAC region and rsing over Africa/Indian Ocean has meant an active Atlantic.
Edit: another thing to point out is that it is an anomaly, not that there will not be any rising air over in the Atlantic basin.

[Hammy]

On today's episode of 2020ing, we have raw, strong westerlies from 50W to Africa south of 12N

https://imgur.com/kSWWStv

That is an extremely EPAC look, as if the CAG and monsoon trough that extends west from it has been shifted to the Atlantic.

[tiger_deF]

This has been the strangest ATL season in recent memory, 2005 may have been more severe but not only has every little piece of vorticity wanted to spin up, but just the generation and wave dynamics seem off

[Hammy]

I did a bit of comparison to last year given both years had a fairly high number of storms vs the hurricane count--we've had five hurricanes by this point, compared to two last year, one of which was barely a hurricane and lasted less than one advisory cycle. This year the reason the ratio is so high is we're seeing a 'typical' above normal setup but the Atlantic is far more unstable than last year.

The end result of this is that a lot of smaller systems that would otherwise remain invests are able to spin up and even reach storm intensity. 2019 by contrast saw quite a few storms either fail to strengthen or fail to develop in the first place when things seemed like they should--in fact there were 2-3 storms that seemed almost guaranteed to develop in late July that simply poofed after a few days.

Comparing the statistics: if you take the two strongest storms up to this point out of the mix, 2020 is at 14/4/0 while 2019 was at 5/1/0--and the ace per storm would be 2.3046 per storm 9 storms contributing over 1 ACE (64%) with Bertha, Dolly, Edouard, and Omar the only ones that didn't. By contrast 2019's being 1.039 per storm--and Barry being the only contributor to reach over 1--a mere 20%.

[TheStormExpert]

On today's episode of 2020ing, we have raw, strong westerlies from 50W to Africa south of 12N

https://imgur.com/kSWWStv

This can happen in active hurricane seasons. Seen it in 2017. However this prolonged event of considerably weak easterlies in the MDR is becoming noteworthy.

https://i.imgur.com/BIPmN3P.png

Is it a positive or negative towards tropical development in the Tropical Atlantic?

[Deshaunrob17]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

Nope.. This is actually a hyperactivity/La nina look for the Atlantic.. Rising air over Africa enhances the tropical waves..Sinking air over the Pacific equals less storms over the Pacific and less wind shear over the Atlantic. This VP set up is ideal for Atlantic hurricanes

[Kingarabian]

Example of how these VP200 graphics can be misleading. The models are keying in on TC activity in the open Atlantic yet the Euro VP200 forecast is for sinking to dominate the region until October.

https://i.imgur.com/wv7CIZ5.png

Nope.. This is actually a hyperactivity/La nina look for the Atlantic.. Rising air over Africa enhances the tropical waves..Sinking air over the Pacific equals less storms over the Pacific and less wind shear over the Atlantic. This VP set up is ideal for Atlantic hurricanes

I know its a positive setup. I'm pointing out how having subsidence over the MDR does not equate suppressed TC activity. This is what people point out during the preseason.

[CyclonicFury]

On today's episode of 2020ing, we have raw, strong westerlies from 50W to Africa south of 12N

https://imgur.com/kSWWStv

This can happen in active hurricane seasons. Seen it in 2017. However this prolonged event of considerably weak easterlies in the MDR is becoming noteworthy.

https://i.imgur.com/BIPmN3P.png

Is it a positive or negative towards tropical development in the Tropical Atlantic?

I'd say positive overall, but it can lead to monsoon trough breakdowns that result in many competing vortices, resulting in the vortices fighting for dominance. IMO, the MDR has not failed to produce a long track hurricane yet due to unfavorable conditions, but rather due to a very strong tropical waves that struggle to consolidate quickly. As I have mentioned, that is likely to change soon, and we should have at least one Cape Verde hurricane to track within the next 10 days.

This season is nothing like a quiet season (i.e. 2013) when shear and large scale subsidence was too much for the Atlantic to overcome.

[Shell Mound]

The 09:00 UTC TWO graphic looks like a plot of updraft signatures for long-tracking, tornado-producing supercells over the Plains/Dixie Alley. This is the first time I’ve ever found myself comparing the Atlantic hurricane season to a major tornado outbreak, but there’s so much activity on the docket that I think the comparison is apt for once. We’ve seen a lot of EF0s and EF1s up to this point, but peak heating hasn’t arrived yet, so the ferocious clusters of EF4s/EF5s, for the most part, are yet to come. Given that the WAR has consistently been very strong so far in 2020, I would be shocked if not one of all the upcoming storms managed to hit the U.S. At this point, the main determinants will be a) timing and position and b) wavelength. If the ridge is too far north, then weaknesses and TUTTs underneath will combine with climatology to draw several of these storms northward. However, I have a sneaking suspicion that, even if most systems manage to curve OTS, at least one long-tracking CV system that originates in the MDR will find a way to strike the U.S., given how many solid TS/(M)H landfalls we’ve already seen up to this point: Bertha, Cristobal, Fay, Hanna, Isaias, and Laura. This indicates that the prevailing steering currents thus far have definitely favoured landfalls, to not mention the fact that the sprawling precursor disturbances, even under the best conditions, usually take time to develop, so systems haven’t really “taken off” prior to reaching the western MDR, Caribbean, and/or nearshore environs in the subtropics. Based on the overall pattern, I think one of the upcoming CV systems could be a long-tracking MH that threatens the Mid-Atlantic and/or Northeastern U.S. (New England): a system that initially tries to curve OTS, but gets blocked beneath ridging and heads up the coast. Systems that develop farther south and west, of course, would be more likely to threaten the Gulf and/or FL, regardless of steering. However, we would definitely need to see a period of blocking rather than the progressive pattern we’ve witnessed over the past week or so.

[gatorcane]

Labor Day weekend 2020 has started and just no real threats to any land areas outside maybe the Cabo Verde islands with a wave to exit Africa this week. Looking at the loop just not much going on outside of some “fruit salad” in the far eastern Atlantic shaded by NHC. Plenty of dry air is still around, here in South Florida hazy skies were widespread today. Also the board feels a bit quiet lately considering the time of year it is which is another indicator no real threats to land that we can see. Let’s hope this good news continues.