Atlantic Tropical Action 2014

[Ground Scouring]

The WRF-ARW is definitely still more on the bullish side lol. Definitely an outlier for now. 

But the initialization handles the current structure better than any other model save the ECMWF, doesn't it?

[Superstorm93]

The WRF-ARW is definitely still more on the bullish side lol. Definitely an outlier for now. 

 

 

 

University of Wisconsin WRF (UWN4) actually has something similar. 

 

[Superstorm93]

By 138 hours the 12z ECMWF has 91L off of OBX with 78 knot 10-m wind gusts 

 

Pressures down to 987mb 

[Superstorm93]

The 12Z HWRF is further S and suggests a weak surface low across Lake Okeechobee meandering over Florida.

[phil882]

Remember when the HWRF use to be a useful model for TCs?

 

Me neither. 

[N. OF PIKE]

http://www.ndbc.noaa.gov/station_page.php?station=41010

 

WNW winds offshore Cape Canaveral. Pressure Slowly Falling

[thewxmann]

Remember when the HWRF use to be a useful model for TCs?

 

Me neither. 

 

Didn't it take 91L to NOLA yesterday? Lolz.

[Srain]

Remember when the HWRF use to be a useful model for TCs?

 

Me neither. 

There was a significant upgrade in early June to the HWRF. It remains to be seen if the upgrade eliminated some of the issues we have seen in years past.

[phil882]

12z ECMWF is definitely closer to the coast than 00z... seems to be in general agreement with the forecast track of Invest 91L

 

[phil882]

There was a significant upgrade in early June to the HWRF. It remains to be seen if the upgrade eliminated some of the issues we have seen in years past.

 

Thats true... but there has been a "significant" upgrade with the HWRF each year and it only seems to be falling further and further behind relative to the rest of the guidance. I'll continue to remain skeptical. 

[Ground Scouring]

12z ECMWF is definitely closer to the coast than 00z... seems to be in general agreement with the forecast track of Invest 91L

There's a huge spread as early as day two…so I would not place high confidence in most of those models. Several of them are likely too fast as well. The ECMWF is the best single bet at this point.

[N. OF PIKE]

   Could be interesting to keep an Eye on the http://www.ndbc.noaa.gov/station_page.php?station=41114 bouy (Fort Pierce)

 

  IF it has any fetch of NE winds that bouy should see a little pop under detailed wave history and specifically by the swell height and swell direction (NNE/NE/ENE) would all be from this spin over next day or two. Lookin to see swell heights move upward from the current .3 heights.  In addition the Jensen Beach cam is also useful in a potential homegrown system as is would the Canaveral bouy(S) to any bump in swell which may show up stream first.

[phil882]

There's a huge spread as early as day two…so I would not place high confidence in most of those models. Several of them are likely too fast as well. The ECMWF is the best single bet at this point.

 

I think the most interesting thing about that plot is that the largest spread is actually in the first 12-24 hours, between models that keep 91L further offshore vs. other models that draw 91L further southwest towards the Florida coastline. Its clear that the system is still dropping off slowly to the southeast, so its still losing latitude. Most of the convection is also south of the center. So if we have any center relocations, which is still possible when the system is relatively weak, it would be favored to relocate southward in the deeper convection where vortex stretching could tighten up the vortex under the deeper towers. 

[Srain]

I think the most interesting thing about that plot is that the largest spread is actually in the first 12-24 hours, between models that keep 91L further offshore vs. other models that draw 91L further southeast towards the Florida coastline. Its clear that the system is still dropping off slowly to the southeast, so its still losing latitude. Most of the convection is also south of the center. So if we have any center relocations, which is still possible when the system is relatively weak, it would be favored to relocate southward in the deeper convection where vortex stretching could tighten up the vortex under the deeper towers. 

Phil, did you mean SW ~vs~ SE?

[phil882]

   Could be interesting to keep an Eye on the http://www.ndbc.noaa.gov/station_page.php?station=41114 bouy (Fort Pierce)

 

  IF it has any fetch of NE winds that bouy should see a little pop under detailted wave history and specifically by the swell height and swell direction (NNE/NE/ENE) would all be from this spin over next day or two. Lookin to see swell heights move upward from the current .3 heights.  In addition the Jensen Beach cam is also useful in a potential homegrown system as is would the Canaveral bouy(S) to any bump in swell which may show up stream first.

 

 

Note the water temperature bobbling between 83-85 degrees F... thats 28-29 C water temperatures, and significantly higher than what the reynolds SST average suggests (SHIPS diagnoses the system under 27.2 C water temperatures). 

[phil882]

Phil, did you mean SW ~vs~ SE?

 

Yep... oops, mixing up my cardinal directions again 

[Derecho!]

Thats true... but there has been a "significant" upgrade with the HWRF each year and it only seems to be falling further and further behind relative to the rest of the guidance. I'll continue to remain skeptical.

It's not really designed for INVESTs so I'd wait for an actual TC to see if it still sucks.

[phil882]

But the initialization handles the current structure better than any other model save the ECMWF, doesn't it?

 

Yea the initialization looked ok for this morning... although I can't remember what ICs it uses (maybe the RAP?)

 

[icebreaker5221]

I too am disappointed we don't have recon today, but essentially all this means is we'll have a TD tomorrow instead of today.  Who knows, even if they found a closed CoC today, NHC might still not make the upgrade due to the lack of sufficient deep convection co-located with the CoC (which has always been somewhat subjective / varies by forecaster). 

 

Would re-iterate that the extra dropsonde and flight-level data would have been nice for assimilation, as it's clear that GFS and GGEM are having difficulty with initialization. 

[phil882]

It's not really designed for INVESTs so I'd wait for an actual TC to see if it still sucks.

 

This is true... but I'm probably not holding my breath. 

[Superstorm93]

Looking at things, 91L really just needs some deeper convection over the center and the system should begin a gradual strengthening trend by lowering pressures and the fact that the LLC is impressive for an invest. 91L should be able to respond quickly once the pressures get low enough 

 

EDIT: LLC visible coming out of convection 

 

[wxeyeNH]

4:30pm EDT LLC becoming exposed for the moment at least.  LLC looks to be stationary or maybe even a slight NW drift.

 

Great site for looping and zooming in.   http://weather.msfc.nasa.gov/GOES/goeseastconus.html

[Ground Scouring]

4:30pm EDT LLC becoming exposed for the moment at least.  LLC looks to be stationary or maybe even a slight NW drift.

 

Great site for looping and zooming in.   http://weather.msfc.nasa.gov/GOES/goeseastconus.html

To be honest, I don't think that there is a well-defined, consolidated vortex yet. The system is clearly tilted from NW to SE, and the mid-level circulation is south of the low-level swirl. I suspect that, with convection firing on the south side, the naked swirl that appears to be the LLC is in fact a mesovortex embedded in a larger low-level vortex. I think that overnight, as convection deepens, a defined center will reform farther south.

[calm_days]

While the low level vorticity clearly has increased, 91L likely will require another 24 to 36 hours to develop as it nears the Gulf Stream. It is also noteworthy that 91L is being somewhat steered by the U/L/ moving W across the Eastern Gulf. The upper sub tropical ridge should continue to influence this motion for the next 72 hours. Until convection increases significantly, the influence of the upper low may allow a SW drift to continue.

 

 

Yes; I feel that to some extent oceanic/gulf dynamics of cyclogenesis, whether it is tropical or otherwise, shift and adjust each year or even over periods of months, in ways that modeling algorithms would not necessarily include.

It is fortunate that these trends can be observed by people, as, together we have some forecast modeling capacity of our own!  

[Superstorm93]

Some significant flip on the HWRF...

 

Now in line with the other guidance in terms of track. The strength is quite impressive as it manages to bring 91L into a solid Cat 2

 

 

 

Also beginning to see the surface pressures drop a bit. 

 

[Hurr_Tracker13]

What I find interesting that could happen///

 

The high to the north as already known, keeps it stationary for a good amount of time, over the warm waters and low shear, this thing could bomb out.

[IsentropicLift]

Is a cat 2 landfall in NC chaseable or do the tight core snobs roll their eyes?

[Akeem the African Dream]

Looks like crap ATTM. Should attain low end ts at some point. Anything else is just a bonus.

[Superstorm93]

00z SHIPS goes with gradual strengthening into a Hurricane 

   *   ATLANTIC SHIPS INTENSITY FORECAST       *
                    * GOES AVAILABLE,       OHC AVAILABLE       *
                    *      INVEST  AL912014  06/30/14  00 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    25    27    29    32    34    38    42    49    55    59    64    66    68
V (KT) LAND       25    27    29    32    34    38    42    49    55    59    64    66    68
V (KT) LGE mod    25    27    29    31    33    37    41    46    52    58    62    66    67
Storm Type      TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP  TROP

SHEAR (KT)        10    11    11     8     9     9     7     6     6     7     8    12    20
SHEAR ADJ (KT)    -1    -4    -6    -5    -5    -3    -4    -4    -3    -4    -2    -2     0
SHEAR DIR        322   329   334   346   341    46    17     7   337   322   294   286   268
SST (C)         27.2  27.2  27.3  27.4  27.5  27.7  27.7  27.5  27.1  26.6  26.4  26.9  26.0
POT. INT. (KT)   124   125   125   126   127   129   129   128   123   118   116   123   114
ADJ. POT. INT.   104   106   106   107   107   107   108   108   104    99    98   104    97
200 MB T (C)   -55.3 -55.3 -55.3 -55.0 -54.6 -54.6 -54.2 -54.4 -53.9 -54.1 -53.7 -53.9 -53.9
TH_E DEV (C)       8     7     8    10    11    10    14    11    15    11    11     5     7
700-500 MB RH     60    57    57    58    55    54    50    52    55    56    57    54    55
GFS VTEX (KT)     10     9     9    10     8     9     8     9     9    10    10    13    15
850 MB ENV VOR   -54   -56   -40   -27   -29   -48   -48   -38   -33   -25     4    10    14
200 MB DIV        -6    -3    -1    -1    -9    16   -12     3    12    22    47    47    67
700-850 TADV      -2    -1     0     0     0     0    -1    -2     2     1    13    17    10
LAND (KM)        316   266   224   179   130    84    68   100   138   144    81    48    52
LAT (DEG N)     29.6  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x  xx.x
LONG(DEG W)     77.6 xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT)     4     6     5     5     3     2     3     5     6     5     7    10    11
HEAT CONTENT      15    15    22    18    25    22    14    16     3     3     1     5     0

  FORECAST TRACK FROM OFPI      INITIAL HEADING/SPEED (DEG/KT):190/  3      CX,CY:   0/ -2
  T-12 MAX WIND:  20            PRESSURE OF STEERING LEVEL (MB):  676  (MEAN=624)
  GOES IR BRIGHTNESS TEMP. STD DEV.  50-200 KM RAD:  17.8 (MEAN=14.5)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD:  20.0 (MEAN=65.0)

[wxeyeNH]

Is a cat 2 landfall in NC chaseable or do the tight core snobs roll their eyes?

Remember northward moving storms on the east coast are going to have the strongest winds to the east of the eye.  So if it stays just offshore or is a coast hugger the Carolinas would be on the wet side with lighter winds.