* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL952020 08/09/20 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 51% 82% LAT (deg N) 9.2 9.4 9.8 9.8 10.0 10.6 11.3 12.3 13.1 13.9 15.1 16.6 18.1 LON (deg W) 27.8 29.0 30.5 32.1 33.1 35.6 38.2 40.8 43.3 46.0 48.9 52.0 55.7 DTL (km) 1246 1367 1516 1661 1624 1577 1590 1466 1335 1222 1182 1165 991 TRACK SOURCE AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 AP09 TCGI 0-48h Genesis Forecast: 51% is 1.7 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 82% is 1.9 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 -2.2 10.3% 1.0 -1.3 15.9% VORTICITY 1.7 2.8 12.8% 1.4 2.6 25.7% VERTICAL SHEAR 16.3 17.1 15.7% 18.4 11.2 24.2% RH 73.1 82.6 -0.2% 70.9 77.3 3.5% GOES 29.1 23.2 1.2% 29.3 23.2 0.9% DVORAK 0.8 1.5 11.5% 0.8 1.5 11.9% --------------------------------------------------------------------------------------------- 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