2022 Indicators (SSTs/SAL/MSLP/Shear/Steering/Instability) and >Day 16 Models

[toad strangler]

From NOAA

NOAA forecasters have slightly decreased the likelihood of an above-normal Atlantic hurricane season to 60% (lowered from the outlook issued in May, which predicted a 65% chance). The likelihood of near-normal activity has risen to 30% and the chances remain at 10% for a below-normal season.

There are several atmospheric and oceanic conditions that still favor an active hurricane season. This includes La Niña conditions, which are favored to remain in place for the rest of 2022 and could allow the ongoing high-activity era conditions to dominate, or slightly enhance hurricane activity. In addition to a continued La Niña, weaker tropical Atlantic trade winds, an active west African Monsoon and likely above-normal Atlantic sea-surface temperatures set the stage for an active hurricane season and are reflective of the ongoing high-activity era for Atlantic hurricanes.

A little lower from NOAA and no mention of specific conditions that might drop it further.

I want to explain why I'm critical on the season buzzwords, read at your own risk.

If someone mentions a word as a reason for a change I want a definition, not just usage of the word. This is not only good for our community, to help explain the term, but also challenges the person using the term to explain what they mean rather than just parrot what someone else says. Quoting from a scientific article that is not applicable to tropical storm formation is not good enough. This keeps the thread interesting and focused on observation and science based discussion.

I know some here will be very annoyed by this but for those of us who have been following the tropics for years the term wave breaking seems to be a convenient reason for a slower than expected season. Why is it showing up this year? Theories are awesome, but why aren't hurricane forecasters with proven track records not mentioning them?

The only scholarly article I can find on wave breaking is Rossby Wave Breaking, with a couple of articles or papers written in the 2008 timeframe and one in 2013. Up until this year the wave breaking term has never been applied to tropical storm formation as far as I can tell (I did not read every page of every article, feel free to correct me). The only mention of wave breaking in an article that also mentions tropical activity that I can find is this: https://www.pnas.org/doi/10.1073/pnas.2010547117 and I can read an abstract of an article here: https://www.jstor.org/stable/26741382

You can search in this thread for wave breaking and see how it was used to define something that seems the exact opposite of what we are hearing about now. If you search all of talking tropics you can find it mentioned as far back as 2018 and applied to just about every condition known. Too warm, too cold, TUTT's, PV streamers, etc.

In short, every season a new theory seems to appear to make it slower than expected. It's really not interesting unless the poster can explain why the theory has merit and how it can be applied to what we are currently seeing. Correlation does not equal causation, which is why many forecasters do not mention these terms without solid evidence that a theory can be show to have a significant effect. My opinion.

Phil does mention in his forecast though,

Cooler-than-normal SSTs in this region have been associated with enhanced wavebreaking into the tropics, which could potentially somewhat counteract the anticipated reduction in wind shear associated with La Niña.

As for studies, I haven't found many of it as well.

Phil used three words in a row. Could, Potentially, & Somewhat in describing the phenomenon. All of which even on their own speak of uncertainty. He's at the TOP of the tropical met food chain. So if he's unsure I'm pretty sure nobody else should be!

[LarryWx]

I had never heard of the term "wave breaking" or wavebreaking" til last month.

By the way, what ever happened to the "pouches"? Do pouches no longer exist?

[skyline385]

I had never heard of the term "wave breaking" or wavebreaking" til last month.

By the way, what ever happened to the "pouches"? Do pouches no longer exist?

Same, never heard of it till last month. It does seem to be the new buzzword which isn't fun when you can't find any studies to read up on it.

[skyline385]

Something interesting to note here is that Phil's forecast is actually on the higher end of the statistical and seasonal models he uses as reference. CSU's own statistical July model dropped to 113 in July from 199 in June and 168 in April which makes me wonder what happened to cause such a jump. The average of all models dropped to 138 as well from 180 and 176 before.

[Ntxw]

Wave-breaking (Rossby) is not a new phenomenon. It occurs throughout the year and helps with mixing the air masses between tropics and polar regions, vice versa. Winter and Summer tends to have longer wavelengths while Spring and Fall tend to show shorter wavelengths, due to the gradient nature of temperatures. The jet stream tends to not buckle as much in the summer with a weaker temperature gradient very far to the north, the only 'unusual' thing if you call it that is the shortening of wavelengths this summer, can be tied to the heat domes over US/Europe buckling the more broad jet than typical. More heat moves north, in between more cool air moves south due to the sharper ridge/trough configuration.

https://www.weather.gov/jetstream/longshort

[Teban54]

Something interesting to note here is that Phil's forecast is actually on the higher end of the statistical and seasonal models he uses as reference. CSU's own statistical July model dropped to 113 in July from 199 in June and 168 in April which makes me wonder what happened to cause such a jump. The average of all models dropped to 138 as well from 180 and 176 before.

https://i.imgur.com/OSI0zKr.png
https://i.imgur.com/nFqD34s.png
https://i.imgur.com/jyu6XEP.png

Question: Are the model forecasts (statistical, global, etc) possibly correlated with the background state when they are initialized? I have always suspected their forecasts can be affected by current conditions, and the July forecasts were initialized with a much more suppressed background state than the June ones. Similar to how global models often fail to pick up the uptick in activity around August 20 until it's already happening.

[tolakram]

Wave-breaking (Rossby) is not a new phenomenon. It occurs throughout the year and helps with mixing the air masses between tropics and polar regions, vice versa. Winter and Summer tends to have longer wavelengths while Spring and Fall tend to show shorter wavelengths, due to the gradient nature of temperatures. The jet stream tends to not buckle as much in the summer with a weaker temperature gradient very far to the north, the only 'unusual' thing if you call it that is the shortening of wavelengths this summer, can be tied to the heat domes over US/Europe buckling the more broad jet than typical. More heat moves north, in between more cool air moves south due to the sharper ridge/trough configuration.

https://www.weather.gov/jetstream/longshort

Does it have anything to do with the canary current or cool waters in the sub tropics?

[LarryWx]

Wave-breaking (Rossby) is not a new phenomenon. It occurs throughout the year and helps with mixing the air masses between tropics and polar regions, vice versa. Winter and Summer tends to have longer wavelengths while Spring and Fall tend to show shorter wavelengths, due to the gradient nature of temperatures. The jet stream tends to not buckle as much in the summer with a weaker temperature gradient very far to the north, the only 'unusual' thing if you call it that is the shortening of wavelengths this summer, can be tied to the heat domes over US/Europe buckling the more broad jet than typical. More heat moves north, in between more cool air moves south due to the sharper ridge/trough configuration.

https://www.weather.gov/jetstream/longshort

Good point. I assumed it wasn't new. But the constant referring to it appears to me to be new. I don't ever recall pattern discussions here and elsewhere with regard to the tropics harping on wave breaking til the last few weeks. So, even though it has always been around, why wasn't it only hardly, if ever, talked about in the past?

[skyline385]

Something interesting to note here is that Phil's forecast is actually on the higher end of the statistical and seasonal models he uses as reference. CSU's own statistical July model dropped to 113 in July from 199 in June and 168 in April which makes me wonder what happened to cause such a jump. The average of all models dropped to 138 as well from 180 and 176 before.

https://i.imgur.com/OSI0zKr.png
https://i.imgur.com/nFqD34s.png
https://i.imgur.com/jyu6XEP.png

Question: Are the model forecasts (statistical, global, etc) possibly correlated with the background state when they are initialized? I have always suspected their forecasts can be affected by current conditions, and the July forecasts were initialized with a much more suppressed background state than the June ones. Similar to how global models often fail to pick up the uptick in activity around August 20 until it's already happening.

That was my first thought as well, particular when you note that the 50-day statistical model has more activity than the July scheme. All models are always initialized with the current environment but here is the issue, we know that the ECMWF SEAS5 and UKMET seasonal models were actually initialized with the June environment since they output their results in early July. The other models I am not sure about, atleast the CSU statistical model (since its not a dynamic seasonal model) should be running on the latest environment which may explain why its so much lower than the others.

[Ntxw]

Wave-breaking (Rossby) is not a new phenomenon. It occurs throughout the year and helps with mixing the air masses between tropics and polar regions, vice versa. Winter and Summer tends to have longer wavelengths while Spring and Fall tend to show shorter wavelengths, due to the gradient nature of temperatures. The jet stream tends to not buckle as much in the summer with a weaker temperature gradient very far to the north, the only 'unusual' thing if you call it that is the shortening of wavelengths this summer, can be tied to the heat domes over US/Europe buckling the more broad jet than typical. More heat moves north, in between more cool air moves south due to the sharper ridge/trough configuration.

https://www.weather.gov/jetstream/longshort

Does it have anything to do with the canary current or cool waters in the sub tropics?

Not that I'm aware of! The only indirect link could be is to enhance TUTT features with mid-latitude air further south via anomalous trough mixing.

Perhaps the Antarctic Circumpolar current is stronger than usual feeding the Canary Current .

[Ntxw]

Wave-breaking (Rossby) is not a new phenomenon. It occurs throughout the year and helps with mixing the air masses between tropics and polar regions, vice versa. Winter and Summer tends to have longer wavelengths while Spring and Fall tend to show shorter wavelengths, due to the gradient nature of temperatures. The jet stream tends to not buckle as much in the summer with a weaker temperature gradient very far to the north, the only 'unusual' thing if you call it that is the shortening of wavelengths this summer, can be tied to the heat domes over US/Europe buckling the more broad jet than typical. More heat moves north, in between more cool air moves south due to the sharper ridge/trough configuration.

https://www.weather.gov/jetstream/longshort

Good point. I assumed it wasn't new. But the constant referring to it appears to me to be new. I don't ever recall pattern discussions here and elsewhere with regard to the tropics harping on wave breaking til the last few weeks. So, even though it has always been around, why wasn't it only hardly, if ever, talked about in the past?

Good question. Predictive lead times for such events is rather short, span of days to maybe a week or two (guidance limitations shows this). So its reliability, in my opinion is only for short stretches of time and better after the fact.

[Stormybajan]

Seeing how quiet the models are for the next 10 days or so my 21-9-5 pre-season prediction is DEFINITELY going to bust lol. Although I did predict 152 ACE which I still think will verify. Phil's new August prediction today is more inline with reality of what this peak season is capable of imo, looks like the models jumped the gun in June, I just felt something holding me back from jumping on that hyperactive train and Im thinking maybe dry air and SSTS not boiling hot were the main culprits? In any case with nothing on the horizon for the next 10 days according to the models to reach CSU's 18-8-4 150 ACE and Noaa's above average forecast it looks like we are going to have to see a lot of activity packed into these 3 months!

Secondly with the whole wavebreaking causing dry air situation due to cool subtropics ( Just when I THOUGHT we were out of the woods dealing with the Subtropical-MDR interference ) Were there any mentions of more SAL and mid-level dry air in 1988 and 2011? These years also had a very similar SST pattern when compared to 2022.

[captainbarbossa19]

I am guessing that 2000 is mainly an analog because it was a 3rd Nina year, but this year is a bit warmer in the MDR. All of these years were either above-average or hyperactive and generally featured somewhat cooler to cool subtropics. Also, note the cooler anomalies off the SW coast of Africa.

[aspen]

https://i.imgur.com/5bfoVH4.png
https://i.imgur.com/fPQStKc.png
https://i.imgur.com/e4fcuWm.png
https://i.imgur.com/aPoOQYt.png
https://i.imgur.com/WgFRO0J.png
https://i.imgur.com/ntbfXve.png
https://i.imgur.com/ARqWRsD.png

I am guessing that 2000 is mainly an analog because it was a 3rd Nina year, but this year is a bit warmer in the MDR. All of these years were either above-average or hyperactive and generally featured somewhat cooler to cool subtropics. Also, note the cooler anomalies off the SW coast of Africa.

2011 has by far the closest SSTAs, both in terms of exact values and distributions — slightly warmer-than-normal MDR with a very cool Canary Current, a warmer tongue north of that, and an Atlantic Nina. 2010 is also surprisingly close too, but the MDR is too warm. 2017’s MDR is also too warm and the Canary Current isn’t nearly as cool as 2010/11/22.

2010 and 2011 were heavy recurve years with early peak season long-tracking majors that either hit the East Coast or got very close (Earl and Irene). Maybe 2022 will be the same.

[Steve]

Some of y’all need to pay better attention to GCANE posts when we have active threats. He’s been talking about Rosby Waves and breaks for years. His contexts genrally relate to specific systems and what upper environments they are heading into. But yeah, literally years. He even draws the depictions on the pics.

[SFLcane]

Highly encourage to read Weathertigers updated outlook for August. His ace model has gone up to 160 for ace. He is good friends with Phil k.

https://weathertiger.substack.com/p/wea ... ricane-d83

[skyline385]

Highly encourage to read Weathertigers updated outlook for August. His ace model has gone up to 160 for ace. He is good friends with Phil k.

https://weathertiger.substack.com/p/wea ... ricane-d83

I am just vaguely familiar with weathertiger, are they claiming here that their predictions are more accurate than the general consensus including NOAA?

[tolakram]

Yes, he is, and admits that with the limited skill data there's a lot of luck involved right now.

Overall, these oceanic and atmospheric conditions are solid predictors of peak season hurricane activity, with WeatherTiger’s model notching forecast skill for August seasonal outlooks since 2016 of over 50%, as seen below. This means the error of our recent forecasts is less than half of simply predicting average activity, similar to or a little lower than August predictions from other forecast groups. Our 2020 and 2021 August outlooks were both accurate to within a few units of ACE, though I’ll be the first to point out that such precision is a combination of some skill and a lot of luck.

[Kingarabian]

Some of y’all need to pay better attention to GCANE posts when we have active threats. He’s been talking about Rosby Waves and breaks for years. His contexts genrally relate to specific systems and what upper environments they are heading into. But yeah, literally years. He even draws the depictions on the pics.

Right lol. Even guys like Eric Webb and Paul Roundy on Twitter.

[skyline385]

Yes, he is, and admits that with the limited skill data there's a lot of luck involved right now.

Overall, these oceanic and atmospheric conditions are solid predictors of peak season hurricane activity, with WeatherTiger’s model notching forecast skill for August seasonal outlooks since 2016 of over 50%, as seen below. This means the error of our recent forecasts is less than half of simply predicting average activity, similar to or a little lower than August predictions from other forecast groups. Our 2020 and 2021 August outlooks were both accurate to within a few units of ACE, though I’ll be the first to point out that such precision is a combination of some skill and a lot of luck.

Thanks, good to hear him admit that a lot of luck was involved