2019 Indicators: SST'S / Sal / MSLP / Steering / Shear / Instability (See updated graphics at first post)

[Kingarabian]

They are coming..

https://twitter.com/stormchaserjs/status/1161958931775799296

WPAC and EPAC had a lot of rising motion this season yet not much TC activity to show for it.

Didn't a lot of the storms get sheared?

Shouldn't rising motion mean more convection thus less shear? Regardless, EPAC shear is near average but instability is lower than average (lack of convection).

[NotSparta]

WPAC and EPAC had a lot of rising motion this season yet not much TC activity to show for it.

Didn't a lot of the storms get sheared?

Shouldn't rising motion mean more convection thus less shear? Regardless, EPAC shear is near average but instability is lower than average (lack of convection).

I've noticed a lot of sheared EPAC storms so I figured that was the problem there.

I do know the WPAC has had no trouble w/ instability but everything until recently was getting sheared into oblivion by the Mei-Yu or a TUTT parade

[Emmett_Brown]

I see that Derek Ortt posted results of a study on seasonal activity back to 1959. He was looking at the number of named storms up to August 15th vs. how many named storms formed in the whole season. Climatology suggests that NOAA's numbers are way too high. We could well see fewer than 10 named storms this year. Note that this is just climatology, and it doesn't take into consideration current naming procedures which are much more liberal than in the past. Of course, that would have meant that we'd only have had 1 named storm up to today way back in time.

https://twitter.com/DerekOrtt/status/1162104940799692800

The bottom graph suggests that the best guess for number of storms post August 15 is 7-8 meaning we have a very long way to go. Best guess for season total as of now is near 10.

Edit: More telling will be where we stand as of 8/31. IF we have no more this month, then we really fall behind. All years since 2001 have had at least one TC genesis 8/21-31. Despite the chance for the GOM storm late next week, it still looks rather quiet vs climo imo.

Very interesting. I am hoping that ACE catches on eventually with the public as a more important gauge of seasonal activity than the number of named storms.

[BYG Jacob]

I really don’t like the CFS predicting that storm outbreak with the current steering.

[Hammy]

CFS showing it's weakest run in quite some time, but still showing what appears to be roughly 10/6/2 through early November, including 6/4/2 for September but doubling down on the western Atlantic and NW Caribbean/Gulf being fairly active.

[Emmett_Brown]

I was curious to see if there is a correlation between N hemisphere and S hemisphere ACE. Ryan Maue has a page that shows current global ACE totals: https://policlimate.com/tropical/

If you scroll down, you can see a chart showing ACE for N Hem and S Hem over the last 4 decades. Generally, there appears to be an overall correlation; when the N Hem is active, the S Hem is usually active, and vice versa. It is not a perfect correlation, but overall, you can see the general tendency. This year, the S Hem finished with an ACE of 273 vs a normal of 209. This suggests it is possible that the N Hem will catch up a bit later in the season. So far, N Hem ACE is 95% of normal. The NIO is much above normal this year, which has helped keep the N Hem close to normal overall.

[Chris90]

I was curious to see if there is a correlation between N hemisphere and S hemisphere ACE. Ryan Maue has a page that shows current global ACE totals: https://policlimate.com/tropical/

If you scroll down, you can see a chart showing ACE for N Hem and S Hem over the last 4 decades. Generally, there appears to be an overall correlation; when the N Hem is active, the S Hem is usually active, and vice versa. It is not a perfect correlation, but overall, you can see the general tendency. This year, the S Hem finished with an ACE of 273 vs a normal of 209. This suggests it is possible that the N Hem will catch up a bit later in the season. So far, N Hem ACE is 95% of normal. The NIO is much above normal this year, which has helped keep the N Hem close to normal overall.

Very interesting idea, thanks for posting. I do think it is worth noting as well that when it comes to the Southern Hemisphere ACE from this past season, a lot of it was generated in the South Indian Ocean, right on the other side of Africa from the Atlantic, and obviously opposing hemispheres, but I'd be curious if there was a further breakdown in this relationship showing a correlation between activity in the SPAC and the WPAC-CPAC-EPAC as opposed to SWIO to the ATL.

Does anyone possibly have a link that breaks down Southern Hemisphere ACE a bit more, dividing between each of the regions? Even if it was just broken down into ACE generated on the west side of Australia compared to ACE generated on the east side of Australia. I've never seen anything that breaks down the SHem ACE, I'm assuming because of the different regions and variety of agencies that issue warnings, it would be a bit tricky.

[cycloneye]

 https://twitter.com/DerekOrtt/status/1162501619969351680




 https://twitter.com/DerekOrtt/status/1162501900119547905

[SFLcane]

https://twitter.com/DerekOrtt/status/1162501619969351680

https://twitter.com/DerekOrtt/status/1162501900119547905

Ok so pack it up folks see you next year. In general things should get more favorable as we move into sept last week of August. EPS this afternoon was quite active across the eastern atl.

[CyclonicFury]

https://twitter.com/DerekOrtt/status/1162501619969351680

https://twitter.com/DerekOrtt/status/1162501900119547905

Wonder where Ortt has been, haven't seen him on S2K in a long time.

I remember him flip flopping a lot in 2017, he said conditions were like 2013 at one point then.

[Hammy]

Latest CFS run appears to show 10-12 storms, 3-5 hurricanes, and 1 major between August 22 and November 14 (with all but one of those occurring after September 1--the exception being a possible short-lived storm off Africa in late August.) Appears to be backing off intensity of MDR activity in October, but it's been going in cycles and this is one of the lowest runs (and past seasons it's ended up somewhere between the lower and higher ends of these model cycles)

[cycloneye]

 https://twitter.com/MJVentrice/status/1162685914407211013

[Shell Mound]

Klotzbach's AMO actually turned positive in July FWIW.

Also, the Atlantic has not behaved like the cool cycle the last three years. Three consecutive above average seasons that were way more active than the 1970-94 average.

True, in fact I just literally quoted the AMO index in my last post in red.

How many more maps, models and graphs do I have to post to prove that things are changing without resorting to the use of cherry-picking?

Note that I did not mention the July AMO value in my post above, only that the AMO appears to have shifted to a cool period starting in 2013, as can be seen below. That spike in July looks quite odd. I suspect that we will see a significant drop in August. During each cool AMO cycles there are years with spikes above normal, as with warm AMO cycles with cool spikes. Generally, though, the Atlantic is in a cool cycle. We won't know until the end of November whether the season averaged out as above or below-normal.

I sent a note to Klotzbach asking his opinion of the July upward spike in the AMO. Will let you know what he things about it.

Ok, enough of this. I now say we're going to see 50 named storms this season, happy?

http://wxman57.com/images/AMO.png

What are some possible reasons as to why the latest +AMO ended faster than the previous known +AMO cycles?

[SFLcane]

Only a matter of time now...

[Hurricaneman]

Only a matter of time now...

https://i.imgur.com/pCetiDh.jpg

Looks like the last few days of August is when when the lid comes off but how many is the question since the pattern is ripe for landfalls

[psyclone]

It's a really tall order to sneak through August without a storm. I don't believe that will be the case. We're getting to the time where the calendar is a huge tailwind and stuff just finds a way to happen.

[NotSparta]

Only a matter of time now...

https://i.imgur.com/pCetiDh.jpg

Looks like the last few days of August is when when the lid comes off but how many is the question since the pattern is ripe for landfalls

It isn't quite ripe, those tracks say "fish" (or Bermuda for the ensembles w/ a stronger ridge), but it looks to become more ripe for landfalls into September. Hopefully, things get less favorable by then, but it's hard to guarantee during peak season

[Hammy]

Didn't the Euro ensembles have a ton of storms in the Gulf as well until it didn't?

[CyclonicFury]

Didn't the Euro ensembles have a ton of storms in the Gulf as well until it didn't?

The ECMWF ensembles have had some phantoms so far this season with 95L and 96L. Many members developed these invests significantly, some even showing hurricanes. Neither invest developed and here we are on August 17 with no TCs so far this month.

[gatorcane]

The trough has been a persistent feature this summer unlike the summers from 2015-2017 (and to some extent 2018) where we had deep east flow. Might be an indicator any storms that do form this year that try to approach from the east of Florida would recurve away.

NWS Miami even mentions how persistent the trough has been in last night’s discussion and you can see the impact to the sensible forecast:

REST OF NEXT WEEK: An upper level low digging towards the Great
Lakes midweek will reinforce the persistent eastern US trough
that has been around for a good bit of the summer. While not as
strong as we`ve seen it earlier this summer, the result will be an
eroding of the western edge of the ridge, with mid-upper level
flow veering out of the south southeast.

https://forecast.weather.gov/product.ph ... glossary=0