Atlantic Tropical Action 2012 - Part II

[wxmx]

I believe there is a small but brief window tonight/tomorrow as shear decreases and conditions become a bit more favorable for development. We will see.

It's funny how the models are so divergent with it. The Euro jettisoning the pieces into a deep trough. The CMC leaving it behind and making it a hurricane in the W Atl, and the GFS leaving it behind and wide-clockwise looping the remnants into Chetumal.

So far, the Euro looks too far north, as the center of the LLC looks already just SE of the Mississippi delta., with the GFS handling it better in the short range. We'll have to see how strong/deep the trough really is.

[wxmx]

By the way, 90L looks heavily sheared and elongated NE to SW, but closed and vigorous...better than yesterday, despite what the 8am TWO said. Convergence and divergence are pretty strong too. If the center can consolidate closer to where the convection is, upper level conditions look a bit better, but I'm not counting on this just yet.

[das]

By the way, 90L looks heavily sheared and elongated NE to SW, but closed and vigorous...better than yesterday, despite what the 8am TWO said. Convergence and divergence are pretty strong too. If the center can consolidate closer to where the convection is, upper level conditions look a bit better, but I'm not counting on this just yet.

You get a real sense of the shear in the GOES-14 SRSO loop. They just repointed the imager at 90L 40 minutes ago. Lots of overshooting tops too so that is somewhat of a good sign.

http://www.ssec.wisc.edu/data/1min/index.php?action=view_animation&req_method=nframes_enddate&enddate=20120906&endtime=1450&nframes=32&band=1&res=1&aniwidth=2400&aniheight=1372#form

[Srain]

It looks like RECON is a go for this afternoon re: 90L and a couple of additional missions have been tasked as well.

[Hurriplane]

Not sure if related but here..

Synopsis: El Nino conditions are likely to develop during September 2012.

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.html

[tornadotony]

OK, I gotcha.

Did you see my post earlier today? I am wondering if the wind speeds for the whole SS scale need to be revised downward to more accurately reflect what's observed on the ground.

As you and I have noticed, an actual 1-min/10-m wind reading of 85 kt from an official land station in a landfalling hurricane always seems so nuclear-- even though this barely qualifies as Cat 2.

This is a partial solution that I would fully support. The SSS was devised when very little was known about wind/height relationships in hurricanes, when either FL winds or pilot estimates of wave action were used to determine hurricane intensity. I would venture a guess that many famous hurricanes that haven't gone through reanalysis yet (i.e. Camille) were pretty overestimated (we've had the Camille discussion before so I won't rehash it).

[Ed Lizard]

I have decided that the GFS post truncation, while worthless for anything resembling 'precision' guidance (but then again, how precise is the 8 day GFS?) isn't worthless for trends. It becomes almost an extra ensemble member running at lower resolution.

During the mid to late July 'season cancel' season, the GFS and the GEFS would show little or nothing in the Atlantic. Most runs would have nothing, including the ensembles (using 1004 mb as a discriminator), and that started to change as August got busier. GFS did predict some AEWs to really go to town and come West, and that didn't always verify. I believe Kirk was an AEW that was advertised as being a potential storm of the season, and drifted Northwest without developing immediately.

Fantasy range GFS and ensembles have been insistent on something roughly timed to match the 74th anniversary of 1938 on several runs during the recent days. Instead of getting too excited, perhaps one can take some hope that the model is persistent, even beyond the resolution truncation. Speaking of, the 18Z GFS op at 192 hours is West and South of most of the 18Z ensemble members, perhaps higher resolution results in a model forecast track that will be closer to the US (as the 18Z ensembles are mostly fish at 372 hours)

I generally agree, it seems like the GFS is handling the 48-72 hour forecast period better... I'm just referring to when Leslie first developed into a TC... the GFS had it all the way up way east of Bermuda in the 180-144 hour time frame. That forecast is not verifying. Its hard to do model verification when it always changes each run

Kyle Griffin's Dprog/Dt map shows this blatant NE bias of the GFS in the longer time fields. It does seem to key into the correct solution within 144 hours, although there were still some runs a little too far to the NE.

http://www.atmos.alb...patl_dprog.html

Phil quote from a different thread, but I do wonder if NE bias is somehow related to resolution, that would obviously amplify at longer time periods (even in the operational between 6 and 8 days). I am wondering, and hope someone has studied, whether Hour 192 GEFS storm forecasts tend to be North and East of the operational model, and whether an increase in resolution, with no other adjustments, would improve GFS TC forecasts by any significant amount.

[wxmx]

You get a real sense of the shear in the GOES-14 SRSO loop. They just repointed the imager at 90L 40 minutes ago. Lots of overshooting tops too so that is somewhat of a good sign.

http://www.ssec.wisc...eight=1372#form

Naked swirl is evident now. Convergence is stronger where the convection is (looking at high res vis), that would lead, IMO, and if it's not already there, to another low farther SW.

[GaWx]

Pre-market trading on Gulf Mandarin becoming Nadine Isaacdottir lower, NHC threatening to canx flight, 40%...

I'm enjoying the usual bull (at least, say, 3/4 glass full)(Aric) vs. the often bear (say, 3/4 glass empty) (57) at that other place. One thing is for sure: if you can get 57 on your side, look out! Who will prevail?

[Ed Lizard]

Naked swirl is evident now. Convergence is stronger where the convection is (looking at high res vis), that would lead, IMO, and if it's not already there, to another low farther SW.

CIMSS shear doesn't look all that terrible. GFS 850-500 mb shear looks a tad stronger than 200-850 mb shear (FSU model page), but I don't even think its mid-level shear. I think convection may just be following better moisture, and it just looks like shear.

[wxmx]

Shear is probably around 15-20kts...not very conducive. Another option, supported by the GFS is that the mid level energy fully decouples from the LLC ... and both die a slow death.

[Srain]

RECON is a no go for today.

[Ed Lizard]

Just deleted the giant CIMSS TPW MIMIC loop, 7 Mb. Big download. http://tropic.ssec.w.../natl/main.html

At Hour 192, GFS has a positively tilted trough that reaches deep into the sub-tropics ready to fish the future Nadine or Oscar. Euro, however, while already at a latitude that crushes hopes for a Caribbean Cruiser or Tight Core in the Gulf, has a solid ridge at 500 mb to the North.

GEFS are all fish. Except one member with a sub-984 mb low that *could* be an ECUSA threat near/just past the 74th anniversary of 1938.

Wishcast mode, a new wave is coming off in close proximity to the future system, and perhaps will either slow development a little, while it drifts West, more than the models expect, or maybe Fujiwaras a system already at the latitude of the CVs a bit Southward before being absorbed. On the TPW loop, while it is big, it also doesn't look all that concentrated.

[Floydbuster]

I have a sneaking suspicion in 2013 we will be waiting for the 8th hurricane season without a major U.S. landfall.

[Srain]

Meh...

[wxmeddler]

RECON is a no go for today.

Global Hawk is taking off at 19z from California and is going to drop 2 sondes from 60kft over 90L on its way to Leslie. Plus all the radar and profiling data that they will get back. Might be of some use.

[Ed Lizard]

I have a sneaking suspicion in 2013 we will be waiting for the 8th hurricane season without a major U.S. landfall.

A certain pro-met who was calling for a dearth of MDR development but US threats from in close development has been both wrong and right. He has been Tweeting recently about how storms aren't becoming hurricanes (except Ernesto) until they reach sub-tropical latitudes, but there have been several CV and almost CV (not going to argue definition) storms, Leslie being one. Just a quick check, Leslie, Joyce and Helene all got classified East of 45ºW. Ernesto wasn't all that much farther West, 49º, and Isaac was 51ºW.

Hard to get CV/CVish type storms across, especially this year. Dry air and fast low level Easterly flow seems to be the reason people are giving for slow strengthening of storms once they have developed. Upper level flow in the tropics doesn't seem all that bad, especially for a warm ENSO. But the dry air and fast Easterlies don't seem to be preventing development in the East and Central Atlantic. Just keeping what forms from becoming impressive. Not getting any sneaky waves close to the Bahamas or in the Caribbean so far.

Looking at 2004 past advisories. Charley, the cream of that crop, has its first advisory at 61ºW. 2005, Rita was almost 70ºW, Wilma was almost 79ºW.

Maybe October will have a late developer. Glass half full type, noticing the SOI isn't screamingly El Niño-ish, 30 day SOI is about -3...

ETA: Charley as the 2004 Cream of the Crop obviously won't be a unanimous decision...

[HurricaneJosh]

I love how we have two hurricanes and a mandarin-- and yet so little to talk about. Just lame.

[PSUBlizzicane2007]

I love how we have two hurricanes and a mandarin-- and yet so little to talk about. Just lame.

At least we finally got a major hurricane.

[The Dude]

Global Hawk is taking off at 19z from California and is going to drop 2 sondes from 60kft over 90L on its way to Leslie. Plus all the radar and profiling data that they will get back. Might be of some use.

I suspect it will be helpful from a research perspective, but I'm not sure how much utility it'll be from an operational one. One of the big problems with these drones is their limited ability to transmit large amounts of data. I know it is transmitting some limited data live, but I suspect we'll have to wait until it lands for things like radar.

[Mike.Ventrice]

Global Hawk is taking off at 19z from California and is going to drop 2 sondes from 60kft over 90L on its way to Leslie. Plus all the radar and profiling data that they will get back. Might be of some use.

This is our first flight of the campaign. This is an environmental Global Hawk, not an overstorm one. So it will be sampling the environment around the tropical cyclone. Since it is the first flight, it will be taking off from Drydan and landing where the campaign is based (Wallops Island, VA). I believe that the next wave that most models are suggesting spinning up in the upcoming week is a future target for potential genesis, and a SAL interaction.

[HurricaneJosh]

So when are getting some good action in the NATL? Not this high-latitude fish crap-- I mean some real cyclones.

Or is that it? Are we finished for the year?

Pro mets, please chime in-- except Adam, cuz I know what he's gonna say and I'm not gonna like it.

[am19psu]

[HurricaneJosh]

[wxmeddler]

This is our first flight of the campaign. This is an environmental Global Hawk, not an overstorm one. So it will be sampling the environment around the tropical cyclone. Since it is the first flight, it will be taking off from Drydan and landing where the campaign is based (Wallops Island, VA). I believe that the next wave that most models are suggesting spinning up in the upcoming week is a future target for potential genesis, and a SAL interaction.

Yeah I was looking at your online schedule, looks like you all have AV6 booked for next Tuesday. I was trying to follow along with the JPL site but I keep getting errors saying that the script can't find the KML. Oh well, just going to have to wait for the mission report..

[Mike.Ventrice]

So when are getting some good action in the NATL? Not this high-latitude fish crap-- I mean some real cyclones.

Or is that it? Are we finished for the year?

Pro mets, please chime in-- except Adam, cuz I know what he's gonna say and I'm not gonna like it.

I was originally afraid of how the atmosphere would be responding to ENSO at this point in time, but it looks minimal thus far (see Paul Roundy's low pass OLR signals - black contours). I'm still thinking towards the latter half of September-early October where we could see another period of increased Atlantic TC activity... These TCs would be the ones associated with AEWs, not PV-type developments.

[HurricaneJosh]

I was originally afraid of how the atmosphere would be responding to ENSO at this point in time, but it looks minimal thus far (see Paul Roundy's low pass OLR signals - black contours). I'm still thinking towards the latter half of September-early October where we could see another period of increased Atlantic TC activity... These TCs would be the ones associated with AEWs, not PV-type developments.

Thanks, Mike. Gives me a little hope.

Do you have any thoughts Re: general regions for development-- or is that getting too specific at this point?

Also, what are you thinking about the EPAC? I'm starting to think that basin, in October of an El Nino year, might be my best chance for a really good chase this year? (If you have any thoughts about it, you can answer in this thread, so as not to drag this one off topic.)

[Ed Lizard]

New 0Z GFS wants to do the slow, lazy Leslie-ish recurve of my potential 1938 74th anniversary storm, but looking at the basic GFS 500 mb pattern, I don't think it is a slam dunk on the recurve. Too early to go 2^-5 type glass full optimistic probs, but roughly/maybe just under glass quarter full optimistic

Closer to my lawn, as the res chop approaches, GFS has moisture and a very subtle low to mid-level wave down BoC way. Maybe making up a word, isovort, but so subtle not even a closed 850 mb 5/s isovort.

[Mike.Ventrice]

Hi all, the first flight of the HS3 campaign has ended and the global hawk has safely landed in Wallops.

[The Dude]

Nice!