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

[USTropics]

Besides the models picking up on activity, observed patterns at the end of August are indicators September will be quite active. I've compared 2020 anomalies to composites of the past 6 hyperactive seasons (2017, 2010, 2005, 2004, 2003, 1999):

Velocity Potential



Precipitation



850mb Zonal Winds



200mb Zonal Winds



500mb Relative Humidity (upper-level)



700mb Relative Humidity (mid-level)

[Hammy]

Agreed with that Toad. Not a fan of it either. Maybe we missed one or two systems a year - at most - back then anyway? Whatever the adjustment is, I don’t think it’s consequential. Anyone with actual data or reanalysis estimates is certainly welcome to educate me on that assumption if I’m wrong.

My point on this was that people are reading too much into the ACE being low for the number of storms and that even one or two weaker ones being missed has a substantial impact on that in earlier years.

[EquusStorm]

So far, as of September 1, this season has been like a big bag of potato chips. You open the bag and there are WAY more chips than there should have been, the bag is literally overflowing more than even should be possible. But most of the extra in the bag, indeed much of the bag, is full of those little broken chips you can't really even dip in anything. Toward the bottom there are a couple handful of big full chips, really good substantial ones.

Then at the bottom of the bag there's a whole chonkin' potato. That's Laura.

Entering September, we are however about to buy a whole second bag of chips; unless we're lucky these may be a lot bigger, thicker sliced, and way saltier.

[Hammy]

CFS continuing to show 3-5 storms in the MDR during September (backing off a bit some from earlier runs) including a few long trackers in the coming week or two, so along with what appears to be at least one Gulf system mid-month still showing us reaching or being close to the Greek alphabet before October.

[Frank2]

Jim Cantore quoting a fellow meteorologist this morning:

Sam Lillo
@splillo
Another tropical storm, another record.
However, ACE climatology really ramps up entering peak season, and 2020 is not keeping up. Currently ranks 36th, and sits just above average. 2011 and 2012 have pretty similar ACE / TS ratios at this point too.

IMHO a matter of "quality over quantity" because Laura was the only strong system so far...

[aspen]

CFS continuing to show 3-5 storms in the MDR during September (backing off a bit some from earlier runs) including a few long trackers in the coming week or two, so along with what appears to be at least one Gulf system mid-month still showing us reaching or being close to the Greek alphabet before October.

I think the CFS is showing the same Gulf system as some of the recent GFS-Para runs.

Models are definitely coming to a consensus on significant MDR activity starting by the end of the week/this weekend, and since they’ve done a terrible job with intensity forecasts this year, I think it’s likely at least one of those systems will become the high ACE long-tracking hurricane we’ve all been anticipating. That’ll help get 2020 back on track in terms of ACE in comparison to other hyperactive years, because it’s finally starting to fall behind (Nana and Omar aren’t contributing very well).

[Steve]

Jim Cantore quoting a fellow meteorologist this morning:

Sam Lillo
@splillo
Another tropical storm, another record.
However, ACE climatology really ramps up entering peak season, and 2020 is not keeping up. Currently ranks 36th, and sits just above average. 2011 and 2012 have pretty similar ACE / TS ratios at this point too.

IMHO a matter of "quality over quantity" because Laura was the only strong system so far...

You don't consider a 90mph Category 1 a strong storm? If you're talking majors, we'v e only had 1. We're only supposed to have 2.5 in any given year.

[TheStormExpert]

Jim Cantore quoting a fellow meteorologist this morning:

Sam Lillo
@splillo
Another tropical storm, another record.
However, ACE climatology really ramps up entering peak season, and 2020 is not keeping up. Currently ranks 36th, and sits just above average. 2011 and 2012 have pretty similar ACE / TS ratios at this point too.

IMHO a matter of "quality over quantity" because Laura was the only strong system so far...

You don't consider a 90mph Category 1 a strong storm? If you're talking majors, we'v e only had 1. We're only supposed to have 2.5 in any given year.

Strongish. In my opinion it’s been nothing short of a quantity over quality season with Laura, Hanna, and Isaias being the only quality storms around. ACE also tells the story.

[Steve]

Agreed with that Toad. Not a fan of it either. Maybe we missed one or two systems a year - at most - back then anyway? Whatever the adjustment is, I don’t think it’s consequential. Anyone with actual data or reanalysis estimates is certainly welcome to educate me on that assumption if I’m wrong.

My point on this was that people are reading too much into the ACE being low for the number of storms and that even one or two weaker ones being missed has a substantial impact on that in earlier years.

I wasn't coming at your point. I was agreeing that gets thrown around too much. Clearly a couple storms extra in a 100 ACE, 10 named storm year could reduce ACE by 8-10% per capita. So it definitely would have a minor impact on average ACE/storm. I still am going to question whether ACE is a significant indicator for anything in the 2020 season, and we won't really know until its over and we calculate and compare.

[Steve]

Jim Cantore quoting a fellow meteorologist this morning:



IMHO a matter of "quality over quantity" because Laura was the only strong system so far...

You don't consider a 90mph Category 1 a strong storm? If you're talking majors, we'v e only had 1. We're only supposed to have 2.5 in any given year.

Strongish. In my opinion it’s been nothing short of a quantity over quality season with Laura, Hanna, and Isaias being the only quality storms around. ACE also tells the story.

Yeah, but chances for anything at all of "quality" really isn't supposed to happen until after August 15th, right? 85% of hurricanes/hurricane activity falls after that date which was just a little over 2 weeks ago. As I've said numerous times, I'm an observer and don't have an agenda on this. So to me, the ACE/storm doesn't really mean anything yet. Rather than looking at it as "quantity over quality", I tend more to look at many of those systems as bonus storms that spun up in spite of most years past where they probably wouldn't have.

[TheStormExpert]

You don't consider a 90mph Category 1 a strong storm? If you're talking majors, we'v e only had 1. We're only supposed to have 2.5 in any given year.

Strongish. In my opinion it’s been nothing short of a quantity over quality season with Laura, Hanna, and Isaias being the only quality storms around. ACE also tells the story.

Yeah, but chances for anything at all of "quality" really isn't supposed to happen until after August 15th, right? 85% of hurricanes/hurricane activity falls after that date which was just a little over 2 weeks ago. As I've said numerous times, I'm an observer and don't have an agenda on this. So to me, the ACE/storm doesn't really mean anything yet. Rather than looking at it as "quantity over quality", I tend more to look at many of those systems as bonus storms that spun up in spite of most years past where they probably wouldn't have.

True, nothing significant is supposed to form before August 15th-20th but it’s also interesting that many of the 15 named storms so far have formed in the Subtropics. Not saying classic Cape Verde season long-tracker ACE producing storms won’t occur at some point but we have four weeks for them to form and occur before that shuts down in late-September, early-October.

[Steve]

You're right on that. And I'm not sure why this year and certainly Toad's "white elephant" year of 2005 had so many systems form outside of the MDR. Hammy noted that there are major differences in "source" for storms between the two years. But she also discussed a couple similarities. Another one that stands out to me is the anomalously warmer water across almost the entire Atlantic basin. We had that in 2005 which I think set the overall + record since they've been measuring. I don't have the 2005 map from 8/31 to contrast, but I remember almost the entire ocean was yellow or orange for much of that season.

https://www.ospo.noaa.gov/Products/ocean/sst/anomaly/

[TheStormExpert]

You're right on that. And I'm not sure why this year and certainly Toad's "white elephant" year of 2005 had so many systems form outside of the MDR. Hammy noted that there are major differences in "source" for storms between the two years. But she also discussed a couple similarities. Another one that stands out to me is the anomalously warmer water across almost the entire Atlantic basin. We had that in 2005 which I think set the overall + record since they've been measuring. I don't have the 2005 map from 8/31 to contrast, but I remember almost the entire ocean was yellow or orange for much of that season.

https://www.ospo.noaa.gov/Products/ocean/sst/anomaly/

2005’s numbers on this day were 13/5/3 compared to our current 15/4/1. Not a huge difference but the two July ACE producers Dennis and Emily surely helped ACE that season get to the level it did.

[EquusStorm]

While there have definitely been some super short lived storms this year I think it's probably important to stress very hard just how ridiculously anomalous Dennis and Emily were; though we've had nasty July hurricanes before it seems statistically extremely unlikely we'll see another July even in the same universe as intense as July 2005 was. I blame July 2005 for forever skewing people's perceptions of pre-August activity; I know a lot of people probably started tracking hurricanes or getting interested in them after that season so if the point of reference for a lot of people is 2005, anything is going to look pitiful. Without those two abnormally early violent hurricanes, we are almost identical to 2005 right now. Behind a lot of other seasons and ahead of others, but 2005 pre-Katrina without Dennis and Emily was very mild if prolific.

If people want to look to a more realistic and achievable extreme level of July activity, I'd point to 2008 with Bertha and Dolly; two category 2+ hurricanes, with one unusually long tracking and far east, but far more attainable than two pre-August 130kt+ hurricanes. With Audrey's downgrade we have nothing even in the same neighborhood before August that compare to EITHER of the July majors in the astronomically incredible 2005 season with its nonstop train of tropical wave spawned cyclones. So people probably should not compare to it lol.

[USTropics]

You're right on that. And I'm not sure why this year and certainly Toad's "white elephant" year of 2005 had so many systems form outside of the MDR. Hammy noted that there are major differences in "source" for storms between the two years. But she also discussed a couple similarities. Another one that stands out to me is the anomalously warmer water across almost the entire Atlantic basin. We had that in 2005 which I think set the overall + record since they've been measuring. I don't have the 2005 map from 8/31 to contrast, but I remember almost the entire ocean was yellow or orange for much of that season.

https://www.ospo.noaa.gov/Products/ocean/sst/anomaly/

For comparisons, here is the observed SSTA graph for 2020 (August 31st) that Steve posted and the past 6 hyperactive seasons on the same date:

2020


2017


2010


2005


2004


2003


1999

[Steve]

Thanks US. Looks like 2017 is really, really close to 2020. All those years have similarities, though ‘17 is bordering on uncanny.

['CaneFreak]

In terms of the upcoming pattern, I thought these 8-14 day CPC analogs might raise a few eyebrows.

[EquusStorm]

Random frontal low NE of Omar says, hey why didn't you invite me to the high latitude lows suddenly developing deep convection and low/mid level swirls party

[aspen]

Random frontal low NE of Omar says, hey why didn't you invite me to the high latitude lows suddenly developing deep convection and low/mid level swirls party

https://cdn.discordapp.com/attachments/485131981043269632/750807458376581120/74077785.gif

Many of the global models were showing a possible STC ahead of Omar for the last few days. Looks like they were right.

2020 seems insistent on blowing through the name list as quick as possible and having at least one of the Greeks become a Big One this season.

[EquusStorm]

Random frontal low NE of Omar says, hey why didn't you invite me to the high latitude lows suddenly developing deep convection and low/mid level swirls party

https://cdn.discordapp.com/attachments/485131981043269632/750807458376581120/74077785.gif

Many of the global models were showing a possible STC ahead of Omar for the last few days. Looks like they were right.

2020 seems insistent on blowing through the name list as quick as possible and having at least one of the Greeks become a Big One this season.

Well it tried extremely hard to do that in 2005 with Wilma/Alpha but NHC missed the Azores STS, now it's pushing as hard as possible to make that happen this time lol