Atlantic Tropical Action 2013

[Mike.Ventrice]

Count the number of TUTT lows lol

 

 

This is a time where the GFS could struggling with the large-scale pattern. It's been extremely difficult forecasting the pattern over the U.S. in the medium-range, as the European and GFS solutions are in a complete 180 with regards to the pattern over the eastern U.S. late. European keeps digging a strong trough over the East around day 7-9, whereas the GFS is building a ridge. You can imagine the differences between the two models with regards to the downstream impacts over the Atlantic. I'm putting more favor into the trough solution over the eastern Atlantic, which suggests a stronger ridge developing over the northern Atlantic with less sub-tropical cut offs over the tropical Atlantic. This solution might favor better prospects for the weak easterly wave over the central MDR to spin up... Something to keep an eye on in future forecasts that's for sure.

[phil882]

 

 

This is a time where the GFS could struggling with the large-scale pattern. It's been extremely difficult forecasting the pattern over the U.S. in the medium-range, as the European and GFS solutions are in a complete 180 with regards to the pattern over the eastern U.S. late. European keeps digging a strong trough over the East around day 7-9, whereas the GFS is building a ridge. You can imagine the differences between the two models with regards to the downstream impacts over the Atlantic. I'm putting more favor into the trough solution over the eastern Atlantic, which suggests a stronger ridge developing over the northern Atlantic with less sub-tropical cut offs over the tropical Atlantic. This solution might favor better prospects for the weak easterly wave over the central MDR to spin up... Something to keep an eye on in future forecasts that's for sure.

 

 

I'm not seeing a favorable pattern on the ECMWF appear until the day 8-10 range. Until then, the TUTT is dominating the central atlantic above 15N. Part of the problem is likely due in part to how stable the tropical and subtropical Atlantic has been this year. Without a lot of deep convection, you don't have a primary mechanism to destroy upper level +PV anomalies via diabatic heating. 

 

 

This is also going to sound backwards, but I also think the very active African monsoon is partially to blame as well for the lack of activity in the MDR. Have you noticed that we haven't gotten very many waves hanging around 10N. Most have been emerging off much higher than usual, partially due this years active EKE and further northward extent of the heavy precipitation (note black contours are climatological values).

 

Now stronger waves normally are a good thing for TCG... and that's true to a point. They are definitely a better thing for early Cape Verde TCG (like what we witnessed with Dorian and Erin). However, strong waves also have a tendency to emerge off at a higher latitude, and tend to have a larger 500 hPa footprint. Therefore in order to prevent these waves from recurving (or moving into colder SSTs from the get go) there needs to be a strong 500 hPa ridge in place to steer them west or even south of due west in the first few days. Thats been largely absent this year thanks in part to the large upper level trough thats been hanging south of the Azores for the last few weeks. 

 

So its a combo of just bad luck... strong waves that are easily carried poleward in the absence of a strong mid-level ridge. If you want a robust cape verde season with many long tracked strong TCs, you need the strong mid-level ridge from the get go. 1995 is a prime example of that (although even in this case, a lot of TCs end up recurving). Note the distinct lack of TUTT features and that most of the TCs that do develop are on a westward heading. 

[HurricaneJosh]

Folks here talk like Africa is the only source.  Have fun with that!  

 

I still think looking to Africa for interesting events this year is a big waste of time.

[Mike.Ventrice]

Folks here talk like Africa is the only source.  Have fun with that!  

 

I still think looking to Africa for interesting events this year is a big waste of time.

 

Josh, I think I have a feeling where you are going with this...  these systems will likely recurve out over the Atlantic, posing minimal threat to the US. While that's the case on most occassions, you still get those easterly waves that develop, but then struggle and continue to propagate towards the west, reamplify and track up the East coast... you never know!

[Ed Lizard]

Folks here talk like Africa is the only source.  Have fun with that!  

 

I still think looking to Africa for interesting events this year is a big waste of time.

 

But except for a possible BoC miracle in 5 to 7 days, there is no sign of anything developing soon.  Longer range ensembles beyond day 10 show lower pressure and enhanced rain in the BoC, but it seems more like bleed over from an active East Pac than anything else.  There are a couple of systems down there at the very end, but almost two weeks away?

 

And no real signs of subtropical development at low enough latitude to help anyone.

 

Below, longer range ensembles trying to see a silver lining in the BoC, and FIM9 tries for the BoC/Gulf miracle, but comes up just a little short...

[AutoPenalti]

African waves lolz. Booooooorrrrrrring.

African recurves FTW.

[Mike.Ventrice]

00Z Euro ensembles up to a 70-80% chance for genesis with regards to the easterly wave pushing off West Africa in the next 2 days. Maximum intensity looks to hold at a tropical storm. Still a 40-50% with regards to the wave over the central-western MDR over the western MDR or eastern Caribbean between day 2-5.

[bluewave]

00Z Euro ensembles up to a 70-80% chance for genesis with regards to the easterly wave pushing off West Africa in the next 2 days. Maximum intensity looks to hold at a tropical storm. Still a 40-50% with regards to the wave over the central-western MDR over the western MDR or eastern Caribbean between day 2-5.

 

Do you have any research on MJO 1 activity following an especially weak interval during the summer? It looks like 

7-15 to 8-15 was one of the weakest signals that we have seen during a 30 day period during the summer.

[Mike.Ventrice]

Do you have any research on MJO 1 activity following an especially weak interval during the summer? It looks like 

7-15 to 8-15 was one of the weakest signals that we have seen during a 30 day period during the summer.

 

I do not You could take a look through the time-longitude hovmoellers I have: http://www.atmos.albany.edu/student/ventrice/ncep/5S-5N/ or http://www.atmos.albany.edu/student/ventrice/hovs/ see if you can eyeball any nice analogs: 

 

I still think 2006 is a nice example but that makes people grumble in here =\

[Ed Lizard]

Good news/bad news on my Day 5-7 Boc/Gulf miracle, 6Z GFS a bit farther North, whatever is there will affect sensible weather possibly as far North as the Rio Grande.  Bad news, it looks even weaker and less likely to develop than on earlier runs.  But it is the closest in time/nearest to land even vaguely potential feature of interest.  Thus, in its own way, it is as interesting as Cape Verde invests likely to fish then die, or die then fish.

[bluewave]

I do not You could take a look through the time-longitude hovmoellers I have: http://www.atmos.albany.edu/student/ventrice/ncep/5S-5N/ or http://www.atmos.albany.edu/student/ventrice/hovs/ see if you can eyeball any nice analogs: 

 

I still think 2006 is a nice example but that makes people grumble in here =\

 

Thanks.  It's interesting that 2006 comes up with some  aspects of the pattern looking similar to El Nino warming

without an actual El Nino being in place. So something else appears to be mimicking certain qualities of

an El Nino for the Atlantic while the Pacific is decidely in negative PDO.

[Ed Lizard]

29 Global Hawk Dropsondes ingested and assimilated into the 0z GFS! (Note the 26th's were rejected (pic#3), but not tonight!)

 

 

Was this data available to other non-US agencies.  Or, does the relative lack of enthusiasm of the 0Z global models (excluding the Canadian, of course) related to extra data ingested into the models about pseudo-invest 25L?  Even the FIM has lost all signs of enthusiasm.

[dtk]

Was this data available to other non-US agencies.  Or, does the relative lack of enthusiasm of the 0Z global models (excluding the Canadian, of course) related to extra data ingested into the models about pseudo-invest 25L?  Even the FIM has lost all signs of enthusiasm.

We didn't assimilate any drops in the 00z cycle (00z 30th is the last point on the time series, touching the border).  Note the two red spikes on the last data point in the 3rd/4th figures, these are the ones that are rejected (gross check) and monitored (by default for the drops from the global hawk).  Based on what I am seeing from the 30th and 26th, they are getting assigned a quality mark to be monitored by default.

 

I'm assuming that the surveillance obs/drops that ere assimilated on the 28th were not from a global hawk mission given the counts (the spike in the first graph on the 3rd last data point).

 

Given that the observations are showing up in the operational dump files, I can only assume they are available over the GTS (meaning all operational agencies will at least have access to the observations).  Whether or not folks decide to assimilate them is another matter.

[Superstorm93]

So who else is ready for 2014 

 

96L is about to emerge into a nice stable environment and probably wont last more than three days just like the ECMWF suggests. This system will probably wind up being a carbon copy of Erin. 

 

 

ECMWF is rather bullish with development, but does very little with it after it develops. 

 

 

[LongBeachSurfFreak]

Checking in here is painful these days. While most in here want some action close to home as an east coast surfer I am totally fine with fish. But struggling tropical storm fish do not produce swell for the East Coast of any significance. So really, this season thus far is good for no one!! (in here of course in reality it’s great for the general population)

 

What is really causing this nightmare season? Is it the dry air? The shear? Both?

[wxmeddler]

We didn't assimilate any drops in the 00z cycle (00z 30th is the last point on the time series, touching the border).  Note the two red spikes on the last data point in the 3rd/4th figures, these are the ones that are rejected (gross check) and monitored (by default for the drops from the global hawk).  Based on what I am seeing from the 30th and 26th, they are getting assigned a quality mark to be monitored by default.

Well, darn... when I checked the image last night I guess it hadn't updated for the 30/0z run yet and got excited prematurely. Thanks for the catch dtk.

[bluewave]

Checking in here is painful these days. While most in here want some action close to home as an east coast surfer I am totally fine with fish. But struggling tropical storm fish do not produce swell for the East Coast of any significance. So really, this season thus far is good for no one!! (in here of course in reality it’s great for the general population)

 

What is really causing this nightmare season? Is it the dry air? The shear? Both?

 

Second lowest August ACE in the Atlantic since 1966. 

 

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2505

[Sunny and Warm]

Second lowest August ACE in the Atlantic since 1966. 

 

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2505

down everywhere.  Here is current ACE compared to YTD normals:

 

region          normal ACE          current ACE

 

global          416                       244

NH               244                       120

SH               209                       192

NATL             30                          8

EPAC            76                         40

WPAC         129                         60

 

Edit to add that the numbers don't necessarily add up due to differences in regional season start/stop dates.

[Superstorm93]

The 12z GFS keeps 96L as a depression or wave and doesn't develop anything else of interest through 192 hours.

It's pretty sad to think that the last time we even saw an eye in the Atlantic was during Sandy last year...

[Ed Lizard]

If 96L doesn't get named, GFS suggests we'll go right to the peak day of the Atlantic season before the next named storm.

 

Just recalling late July talk that mid-August would be the switch, and now the end of August, and at best a weak and fishing TC, what is the lowest seasonal ACE post 1995, and what is the lowest seasonal ACE of the satellite era?

 

If the season is going to be record boring, might as well set a record doing it.

 

 

Edit to Add

 

 

My natural optimism is being tested.  Usually, I hope Summer never ends, but now I am welcoming the return of the mid-latitude Westerlies around September 10th, because there are no storms to come anyway, and the once a week cold fronts will be more exciting that this.

 

Plus with a possibly active East Pac as shown on models, and a sub-tropical connection from said East Pac, another October 1994 East Pac Hurricane Rosa scenario, with the San Jacinto river catching fire, if that comes early this year.

 

Ok, negativity over, Canadian developing the Central Pac wave no reliable guidance likes into a hurricane that may be about to get trapped under the ridge and turned into Charleston, SC.  I hope I'm not 5 posted for attaching the unlikely and unreliable, but I suspect I don't need more than 5 posts a day the next 2 weeks.  And some day, the Canadian will be almost correct on a 7.5 day forecast.  And the board needs straws to grasp at.

[HurricaneJosh]

If the season is going to be record boring, might as well set a record doing it.

 

I actually agree.  At this point, I'm just rooting for extreme lameness-- just to make it interestin'.

 

11 Sep is the modern (i.e., satellite) era record for latest formation of the first 'cane.

[Mike.Ventrice]

I kinda like 96L chances here. It's currently superimposed with the strongest part of the negative CCKW phase.. You tend to see you best chances of a TC to spin up about 2 days after the day of superposition (if the easterly wave moves or will move over ocean). I wonder what will win, the CCKW or the unfavorable seasonal-intraseasonal state over the Atlantic not associated with the CCKW?

 

 

Also if you visit Alan Brammer's p(prog)/dt of the GFS op, you can see by looking at MSLP that at the 00 hour forecast, the current minimum pressure of 96L is being observed much further south near Senegal than what the GFS has been representing it once in forecast mode (placing it way up over northwest Africa).

 

I guess to be seen..

[Sunny and Warm]

I actually agree.  At this point, I'm just rooting for extreme lameness-- just to make it interestin'.

 

11 Sep is the modern (i.e., satellite) era record for latest formation of the first 'cane.

It's gonna be close Josh.  Who would have thought on June 1st we'd be sitting at 5-0-0 at the end of August with a warm MDR and La Nina-ish tendencies..  All hail the SAL and TUTT's

[Sunny and Warm]

I kinda like 96L chances here. It's currently superimposed with the strongest part of the negative CCKW phase.. You tend to see you best chances of a TC to spin up about 2 days after the day of superposition (if the easterly wave moves or will move over ocean). I wonder what will win, the CCKW or the unfavorable seasonal-intraseasonal state over the Atlantic not associated with the CCKW?

 

 

Also if you visit Alan Brammer's p(prog)/dt of the GFS op, you can see by looking at MSLP that at the 00 hour forecast, the current minimum pressure of 96L is being observed much further south near Senegal than what the GFS has been representing it once in forecast mode (placing it way up over northwest Africa).

 

I guess to be seen..

Do you believe then that the guidance is showing too much recurve into the stable air too quickly??

[HurricaneJosh]

Since it's gonna recurve anyway, I hope it doesn't form.

[wxmeddler]

NOAA49 (Gonzo/ G-IV) just landed in St. Croix for a high altitude radar mission for P25L. It should help supplement the dataset that the Global Hawk collected yesterday.

[GaWx]

Folks,

 We have kind of an interesting situation regarding pouch 25 in the central Atlantic. Whereas the GFS and Euro runs (through 12Z) continue to do nothing with it, the CMC for at least the 4th run in a row has it become a cat 2-3 hurricane and threaten the US east coast. As a matter of fact, today's 12Z CMC actually slams Wilmington with a 968 mb hurricane at hour 216. See the attached map. Actually, it forms a TD by Monday morning 9/2 (72 hours) near the Leewards. Normally, I wouldn't give the CMC the time of day when the GFS and Euro are far different due to its inferiority and tendency to show false TC's. Therefore, I rarely post CMC maps and I'm not one to hype the tropics without a sound meteorological reason. Furthermore, I'm still not betting on it scoring a coup as of now. However, and this is a big however, the MJO is now getting close to an amplitude of 2.00 in phase 1 and rising further. If the Euro and GFS ensemble mean MJO forecasts were to verify, it would peak near 2.30 in phase 1 ~9/1-2, which is consistent with what the Euro has been showing for days. A 2.30 amplitude MJO in phase 1 would be the 2nd strongest MJO in either phase 1 or phase 2 near the peak of the season (8/21-9/20) since at least 1975! It would just beat the 9/5/81 peak of 2.21. Here are the two strongest as of now and the TC geneses while the MJO was 1.50+ in phase 1 or 2 just for the storms that eventually became hurricanes:

 

-3.08 peak 8/28/79: cat 5 David, cat. 4 Frederic, cat 2 Gloria

-2.21 peak 9/5/81: cat 1 Emily, cat 3 Floyd, cat 2 Gert

 

 Actually, a whopping six total TC's formed during the strong 1979 MJO!

 

 So, I'm wondering if it is possible that the Euro and GFS are not responding enough to this strong phase 1 MJO being that we're looking at about a one in 15 or so year event near the season's peak. Could it be that the CMC is responding more appropriately?

 

Any opinions?

 

 

 

[thewxmann]

Checking in here is painful these days. While most in here want some action close to home as an east coast surfer I am totally fine with fish. But struggling tropical storm fish do not produce swell for the East Coast of any significance. So really, this season thus far is good for no one!! (in here of course in reality it’s great for the general population)

 

What is really causing this nightmare season? Is it the dry air? The shear? Both?

 

That's what I personally wanna know. Shear has been above average over the E ATL and the Caribbean. There will always be dry air. Maybe subsidence downstream from an active W African Monsoon? Above average background SLPs? I honestly don't know. I think this season proves we still have a long ways to go with seasonal forecasting. Sometimes things happen without a very obvious cause.

[thewxmann]

I actually agree.  At this point, I'm just rooting for extreme lameness-- just to make it interestin'.

 

11 Sep is the modern (i.e., satellite) era record for latest formation of the first 'cane.

 

Yep. I wouldn't mind going to entire season without a hurricane at this point -- that way we can all say we lived to tell the tale.

[LongBeachSurfFreak]

I like the subsidence idea. Whatever is going on its a multi-year situation. it’s not that we haven’t seen development the last few years it’s that we haven’t seen ideal conditions in the MDR for anything more than struggling trop storms.

I think climate change may have some impact as we see shear increasing in the tropics in general. This fits in with the idea that despite warming sea surface temps increasing shear will counteract any increase in available energy.