Bailey1777 wrote:if no models are latching on what is that intensity chart made up of?
No
global models, which are dynamical, are redeveloping Gaston to any great degree.
The intensity chart shows these models:
SHF5 = SHIFOR5 (Statistical Hurricane Intensity Forecast). Basically the intensity version of CLIPER (CLImatology and PERsistence). "The predictor variables include: (1) Julian day; (2) current storm intensity; (3) intensity change during past 12 hr; (4) initial storm latitude and longitude; and (5) zonal (east-west) and meridional (north-south)." Because it is purely statistical, it will always trend back toward climatology.
SHIP= Statistical Hurricane Intensity Prediction Scheme (SHIPS). Combined statistical-dynamical intensity model. "The primary predictors are:
Current storm intensity;
Day of the year;
Persistence (intensity change in previous 12 hrs);
East-west compontent of storm motion;
Divergence of the wind at 200 mb;
Intensification potential (the difference between the current storm intensity and an estimate of the Maximum Possible Storm Intensity determined from the sea surface temperature);
The vertical shear of the horizontal wind in the 850-200 mb layer;
Average 200 mb temperature;
Average 850 mb vorticity;
Average 500-300 mb layer relative humidity;
Cloud top temperature as measured by the GOES satellite infrared imager channel and
Oceanic heat content inferred from altimetry measurements from polar orbiting satellites."
DSHP = Decay-SHIPS. "The DSHP is identical to the SHIPS model except, if the cyclone is forecast to cross land, the intensity is reduced accordingly."
GFDI=Previous cycle GFDL, adjusted
GHMI=Previous cycle GFDL, adjusted using a variable intensity offset correction that is a function of forecast time.
HWFI=Previous cycle HWRF, adjusted
LGEM = Logistic Growth Equation Model
"LGEM is a statistical intensity forecast model that uses the same input as SHIPS but in the framework of a simplified dynamical prediction system, instead of a multiple regression. The evolution of the intensity is determined by a logistic growth equation that constrains the solution to lie between zero and the TC's maximum potential intensity (MPI), where the MPI is estimated from an empirical relationship with sea surface temperature (SST). The forecast of the maximum wind depends on the growth rate coefficient, which is estimated from a subset of the input to the SHIPS model. Ocean heat content and other parameters derived from geostationary satellites are also incorporated into the LGEM. "
ICON = Average of LGEM, HWFI, GHMI, and DSHP
Based on these descriptions, I would disregard SHF5 since it is only statistical and has no knowledge of the synoptic situation. The pairs SHIP/DSHP and GFDI/GHMI are each variations on the same theme. And the utility of ICON depends on the strength of its individual members. Obviously then, while someone noted 7 members showing Cat 1 intensity, not all of them are independent; and since none of the intensity models have performed well of late, one has to take their results with a grain of salt.
Sources:
Technical Summary of the National Hurricane Center Track and Intensity ModelsAn Overview of NHC Prediction ModelsBTW, from
NHC's 2009 verification report, "LGEM was so superior to the other models in 2009 that it bested the ICON consensus, the latter being negatively influenced by the dynamical models. Still, an evaluation over the three years 2007-9 (not shown) indicates that ICON is slightly superior to LGEM."
take it to the PMs......now I just wasted even more space on this thread by commenting...I blame you... 
LOL!
: Yeah Bvigal, that's why i posted them 
... what can i say, confused for the NHC too 
