* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL952020 08/11/20 12 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 50% 68% LAT (deg N) 13.4 13.8 14.3 14.7 15.1 15.8 16.6 17.6 18.3 18.9 19.2 19.5 19.7 LON (deg W) 36.7 38.3 39.8 41.4 43.1 46.5 50.2 54.0 57.8 61.3 64.2 66.2 68.0 DTL (km) 1844 1787 1691 1599 1520 1372 1278 1069 834 470 186 109 118 TRACK SOURCE TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 50% is 1.7 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 68% is 1.6 times the sample mean ( 43%) --------------------------------------------------------------------------------------------- INDIVIDUAL PREDICTOR CONTRIBUTIONS TO PROBABILITY OF GENESIS ******* 48-HR ****** ******* 120-HR ****** AVG TCGI CONT AVG TCGI CONT DIVERGENCE -1.0 0.1 5.6% 1.0 -0.4 12.0% VORTICITY 1.7 1.7 9.1% 1.4 1.8 19.0% VERTICAL SHEAR 16.3 11.1 18.8% 18.4 19.3 18.5% RH 73.1 60.1 -0.1% 70.9 58.8 1.7% GOES 29.1 19.8 1.0% 29.3 19.8 0.7% DVORAK 0.8 2.0 16.1% 0.8 2.0 16.2% --------------------------------------------------------------------------------------------- PREDICTOR DEFINITIONS (Averaged Over 500 km Radius) GENESIS CLIM = Climatological Prob (%) of Genesis (Source: NHC-TAFB Invest Database) DIVERGENCE = GFS 850 hPa Horizontal Divergence (x10-7 s-1) VORTICITY = GFS 850 hPa Vorticity (x10-6 s-1) VERTICAL SHEAR = GFS 200-850 hPa Vertical Shear (kt) RH = GFS 600-850 hPa Relative Humidity (%) GOES = GOES Water Vapor Pixels Colder than -40C (%) DVORAK = Dvorak T-number, source: TAFB Version 3.0, July 2018