Atlantic Tropical Action 2013 - Part 2

[DopplerWx]

just got renumbered, prolly a TD at 5

[Mike.Ventrice]

Just upgraded to TD7

[tmagan]

System should have its own thread now.

[EasternUSWX]

just got renumbered, prolly a TD at 5

50% at 2pm to td at 5pm. Good stuff. Honestly should be ts already but whatever

[Superstorm93]

BEGIN
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invest_RENUMBER_al972013_al072013.ren
FSTDA
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040
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201309042009
NONE
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[Superstorm93]

Recon shows that the center is directly under the new convection, 

 

 

[Ed Lizard]

It would be at approx 20N, 33W according to those model depictions.  I recall Don S doing a study once at Eastern that showed how rare a tropical system was that made it all the way to the US Mainland from anywhere north and east of 20N, 60W.  This is progged to be 27 degrees further EAST than that line in the sand.  Ain't gonna make it.

 

There was one storm that came from North and East of 20ºN and 50ºW to ensure I wasn't able to party at the beach in 2009.

 

 

I think that happened only because I assured people on a couple of weather forums Ike could not get into the Gulf.  I don't do that anymore, so that will never happen again.

[Ed Lizard]

AP08 looks like the 1933 Potomac Hurricane Track.

 

 

Stronger than 996 mb to.

[Big O]

New invest over eastern MDR, HS29L?

 

 

I wonder if this is designated for the HS3 field campaign? GFS indicating increased low-level vorticity collocated with convection.....

 

 

 

What's that in the southern and western GOM? 

[Sunny and Warm]

There was one storm that came from North and East of 20ºN and 50ºW to ensure I wasn't able to party at the beach in 2009.

 

 

I think that happened only because I assured people on a couple of weather forums Ike could not get into the Gulf.  I don't do that anymore, so that will never happen again.

[Ed Lizard]

 

 

Um,we had plenty of beach season right through Labor Day 2008.  Read my post again.  It was Summer 2009 that was cancelled.

 

Popo, me, and a fish. 2011.  The Playa Party Pad 2.0 was swinging that Summer.

 

[Sunny and Warm]

Um,we had plenty of beach season right through Labor Day 2008.  Read my post again.  It was Summer 2009 that was cancelled.

 

Popo, me, and a fish. 2011.  The Playa Party Pad 2.0 was swinging that Summer.

 

I see what you mean now.  which one was the fish again?? 

[Ed Lizard]

I see what you mean now.  which one was the fish again?? 

 

We went down there once in 2009, it was sort of cool, the houses on stilts that halfway fell into the ocean, but half the house still standing.  They were installing new power poles the day we were down.  There was a fishing pier that was totally wrecked, and later there was a TWC Storm Stories about the Darwin candidates who ran the bait shop and lived in an apartment above it.  They lived.

 

6 days w/o power, the live oak lost all its leaves but lived, and parts of the neighbor's roof wound up on my lawn, but our house was completely undamaged.  We're over 50 miles inland, and, IIRC, per the graphic only had 70-80 mph sustained winds.

 

I preferred fishing behind the Flagship.  Nice older Vietnamese couple ran the bait shop there, and also charged for the parking behind the hotel.  Now the company that own's Landry's has opened a miniature amusement park called the Pleasure Pier, $10 I think just to get in, not ride on any rides.  Same group owns the Kemah Boardwalk, which got trashed in a mere tropical storm about 1998 and then really trashed by Ike.

 

They tore down the Flagship, like I said,  I think they could have repaired it.  Whe we drove by, my wife thought I was a tard for suggesting the corner rooms would have been awesome for a hurricane party.  I try to keep misty, fond memories, like drinking wine and talking Spanish with the Salvadoran neighbors.  The wind came up long before the rain started, actually could see power flashes in the distance.  That part was cool. But my wife's aunt lost her roof and heat/AC and didn't get it fixed until December, and the Archdiocese decided not to rebuild the parochial school at St. Charles Borromeo where my wife's cousin went to school.  (My wife was in the same high school class as her aunt, she is older, her mother and grandmother were pregnant at the same time.  Like a Steve Martin movie, but real).   Took the Archdiocese a couple of years to raise the funds to start rebuilding St. Mary's Co-Cathedral, which still hasn't opened yet.

 

Oh, plenty of convection in the Gulf, mainly with the weak 500 mb feature ahead of the lemonized wave, but I see no signs of organization down there.  I'd like a depression or storm, we need the rain.

 

 

 

[jordanwx]

Hmmm, I wonder what would cause RH to be lower in the tropics, higher in the subtropics and lower in the mid-latitudes across the Atlantic....

 

 

You obviously have a theory...

 

I think it's fairly obvious

 

 

Warmest SSTs are along 30-50N. Hadley cell is broadened and weakened as a result. Meridional overturning within Atlantic weakens as a result = less rising air, vertical instability, etc on the equatorial side of the Northern Hemisphere's Hadley cell (aka MDR). Reason for these warm mid-lat SST anomalies largely a result of -PDO (run a PSD correlation test between SSTA and PDO and you'll see). Shouldn't be too surprising to see the PDO behind much of this, PDO strongly modulates NHemi ACE (Maue 2011). Thinking PDO and ENSO state (which are both deeply connected) are two biggest contributes to this year's global downturn in NHemi ACE...background GW may also play a part but it's hard to say how it may be influencing things and it's not something I'd like to debate lol.

[am19psu]

Awwww, you gave it away

[jordanwx]

I asked about my intuitive suspicion the IOD would mean less rain in Africa (more SAL) and weaker waves, and was told the IOD was a positive for an active season.  Just an amateur hunch, perhaps the effects of IODs the IOD phase is more complicated than people think.

 

 

Edit because original phrasing reminded me of birth control device and sounded funny.

I'm not sure exactly what you were trying to say here, but just to clarify, the negative IOD phase is more favorable than positive phase. Having warm water off the east African coast (positive IOD) will induce more oceanic convection (less over Africa) and also limit moisture transport north and west into the Ethiopian highlands (AEW genesis region). This relationship is akin to looking for the Gulf of Guinea to be cool for a healthy wave train. Furthermore, a negative IOD puts the atmosphere in a more La Nina-like state (as opposed to an El Nino-like state during a positive IOD) which is obviously more favorable for the Atlantic.

[thewxmann]

 

 

I think it's fairly obvious

 

Warmest SSTs are along 30-50N. Hadley cell is broadened and weakened as a result. Meridional overturning within Atlantic weakens as a result = less rising air, vertical instability, etc on the equatorial side of the Northern Hemisphere's Hadley cell (aka MDR). Reason for these warm mid-lat SST anomalies largely a result of -PDO (run a PSD correlation test between SSTA and PDO and you'll see). Shouldn't be too surprising to see the PDO behind much of this, PDO strongly modulates NHemi ACE (Maue 2011). Thinking PDO and ENSO state (which are both deeply connected) are two biggest contributes to this year's global downturn in NHemi ACE...background GW may also play a part but it's hard to say how it may be influencing things and it's not something I'd like to debate lol.

 

 

Who are you? You seem to know your stuff lol.

 

I've seen this warm anomaly in the higher latitudes for years now. Figured it had an influence.

[CoastalWx]

 

 

I think it's fairly obvious

 

 

Warmest SSTs are along 30-50N. Hadley cell is broadened and weakened as a result. Meridional overturning within Atlantic weakens as a result = less rising air, vertical instability, etc on the equatorial side of the Northern Hemisphere's Hadley cell (aka MDR). Reason for these warm mid-lat SST anomalies largely a result of -PDO (run a PSD correlation test between SSTA and PDO and you'll see). Shouldn't be too surprising to see the PDO behind much of this, PDO strongly modulates NHemi ACE (Maue 2011). Thinking PDO and ENSO state (which are both deeply connected) are two biggest contributes to this year's global downturn in NHemi ACE...background GW may also play a part but it's hard to say how it may be influencing things and it's not something I'd like to debate lol.

 

 

I don't think it's quite that easy. 

[Ed Lizard]

Awwww, you gave it away

 

I suspected you were talking Hadley, but otherwise assumed the wrong thing.

 

It happens.

[Ed Lizard]

Way too many smilies going back and forth.

 

If the theory is global warming is involved, I'd like to think it'd take more than a decade from 2004, 2005 and 2008 to a massive slowdown of the Atlantic tropics.  When I see things that suggest Hadley cells being displaced, I assume people are talking climate change the PDO  I don't do that forum.  I'm not even banned there, but too many arguments.

Fixed it.

[CoastalWx]

Correct me if I'm wrong, but hasn't Africa had a normal (sufficient) amount of waves? Also, these features Jordanwx brought up just didn't appear overnight. If it were that easy, wouldn't tropical experts have seen this and toned down expectations? We've had these conditions before, but this year is anomalous so far as to low TC activity. If it were so obvious, I would think TC expectation would've been toned down.

[Ed Lizard]

I'm not sure exactly what you were trying to say here, but just to clarify, the negative IOD phase is more favorable than positive phase. Having warm water off the east African coast (positive IOD) will induce more oceanic convection (less over Africa) and also limit moisture transport north and west into the Ethiopian highlands (AEW genesis region). This relationship is akin to looking for the Gulf of Guinea to be cool for a healthy wave train. Furthermore, a negative IOD puts the atmosphere in a more La Nina-like state (as opposed to an El Nino-like state during a positive IOD) which is obviously more favorable for the Atlantic.

 

I intuitively figured cooler waters near Africa mean less moisture transport inland, drier land and weaker waves.  I was told it doesn't work that way, but somehow what was supposed to be a supporting factor for an active MDR season has not been working out.  BTW, mildly warm ENSO years like 2004 weren't half bad.

 

 

Edit

 

Now, cooler water strategically located on the Atlantic side to concentrate the best upward motion, that I can understand, but I don't know how that relates to the IOD,

[wxtrackercody]

Visible satellite imagery before the sun went down revealed a broad surface low in association with the tropical wave in the eastern Bay of Campeche. Anticyclonic flow aloft +warm waters + a day or two before moving inland = glass-half-full-optimism for a quick spin-up.

 

http://www.ssd.noaa.gov/goes/east/gmex/vis-animated.gif

 

Meanwhile, the GFS continues to be incredibly bullish with the wave over western Africa. 20% chance 5-day formation probability from the NHC.

[HurricaneJosh]

I just wanna break the 11 Sep record for latest first hurricane, so I hope Gaby and everything else over the next week just dies.     I want the craptastic exceptionalism of this season-- and our resultant suffering-- to be marked in the record books.

 

I'm in a spiteful, nihilistic mood about the tropics.  Screw these fishy crap systems.

[AvantHiatus]

I just wanna break the 11 Sep record for latest first hurricane, so I hope Gaby and everything else over the next week just dies.     I want the craptastic exceptionalism of this season-- and our resultant suffering-- to be marked in the record books.

 

I'm in a spiteful, nihilistic mood about the tropics.  Screw these fishy crap systems.

In any other "normal year"; this would of been a Florida crusher as Gaby is passing through the infamous "Hebert Box".

[Ed Lizard]

Visible satellite imagery before the sun went down revealed a broad surface low in association with the tropical wave in the eastern Bay of Campeche. Anticyclonic flow aloft +warm waters + a day or two before moving inland = glass-half-full-optimism for a quick spin-up.

 

http://www.ssd.noaa.gov/goes/east/gmex/vis-animated.gif

 

Meanwhile, the GFS continues to be incredibly bullish with the wave over western Africa. 20% chance 5-day formation probability from the NHC.

 

0Z NAM and 0Z GFS both have closed circulations at landfall, but 15 to 25 knot winds, may not ever get numbered.  Verbatim.  Both Northern Vera Cruz or Southern Tamps.  Might get lucky, a bit stronger than that. but doesn't look very organized and has less than 2 days.

[Floydbuster]

Holy cow

 

[Ed Lizard]

Bed time, but just noticing how the 500 mb pattern doesn't change much through 5 1/2 days, such that I don't think its impossible the Cape Verde wave gets close enough to the USVI for a recon before it fishes.  It should come West a fair ways.

 

GFS- Gabrielle almost looks like it weakens enough to maybe escape the trough and stall as a weak system.  Just South of Bermuda, if shallow enough, looks like the 700 mb ridge may build far enough out into the Atlantic to start it heading back West or Southwest.  Glass eight full.  It'd be between 25 knot and 45 knot 250 mb wind barbs, per GFS, so it should be a shallow system.  May decouple then die.  But maybe not.  Just through 5 1/2 days, bed time.

[jordanwx]

I don't think it's quite that easy. 

I don't either. However, ENSO is neutral to La Nina, EPAC has been well below average in ACE, SSTs in the tropical Atlantic are above average, the African wave train has been healthier than normal, clearly there is a bigger problem. Personally, I think that problem is the subtropical SST profile. In fact, I think the subtropical SST profile is the single biggest reason this season has been a bust so far. Even if we don't finish with a bust, it is true that vertical instability and downward motion remained over basin through most of June-August. That has changed a bit recently with a strong return of the MJO, however. Anyway, on to the evidence. Below I have compared the SST anomaly over the subtropical Atlantic during the top 10 ACE years minus bottom 5 ACE years to SST anomalies this year so far:

 

SST Anomalies for Top 10 ACE Years Minus Bottom 5 ACE Years:

 

 

SST Anomalies for June-August 2013:

 

 

The first image tells us what kind of SST Anomaly profile we want for an active season -- warm tropical SSTs (obviously), warm SSTs around 30-50N between 40-15W and a block of cool SSTs extending off the east coast to about 40W from 30-50N. The second image shows us how SST Anomalies have been so far this season. The tropical Atlantic has been above average, but the region from 30-50N between 40-15W has been much colder than average (where we want it warm) and the region off the east coast has been much warmer than average (where we want it cold).

 

So there you have it, the subtropical SST profile is completely out of wack. Looking at 500mb height anomalies, this has pushed the subtropical ridge further north than normal (broadening Hadley cell) and also brought anomalously high pressure from 30-50N.

 

 

What do you get underneath that anomalous ridging? Convergent flow, how's 500mb omega looking south of the anomalous ridging (~35N)?

 

Sure enough, downward motion starts just on the southern periphery of that anomalous ridging (i.e. that strong band of positive anomalies extending across the entirety of the Atlantic between 30-25N). Further down south in the MDR we have even more downward motion...as previously mentioned subtropical SSTs likely playing a big part in the meridional overturning within the Atlantic, causing upward motion in the deep tropics to suffer. Forcing from strong upward motion over adjacent regions (epac and african continent have both been experiencing strong upward motion) is also hurting the Atlantic (through simple conservation of mass).

[jordanwx]

I intuitively figured cooler waters near Africa mean less moisture transport inland, drier land and weaker waves.  I was told it doesn't work that way, but somehow what was supposed to be a supporting factor for an active MDR season has not been working out.  BTW, mildly warm ENSO years like 2004 weren't half bad.

 

 

Edit

 

Now, cooler water strategically located on the Atlantic side to concentrate the best upward motion, that I can understand, but I don't know how that relates to the IOD,

During the summer months, the ITCZ sits pretty far north from the equator over Africa. Winds over the Gulf of Guinea and the Indian ocean want to blow toward that convergent zone because it is an area of lower pressure. The cooler the SSTs are, the greater the difference in temperature (and pressure) there will be between the ITCZ and the more moisture will be transported north. It's no different than a localized sea-breeze effect...you need those temperature differences to create the winds to draw the moisture from the ocean.