* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL972020 09/13/20 00 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 34% 34% LAT (deg N) 15.6 16.4 16.6 17.0 17.5 19.1 20.3 21.5 23.0 24.0 25.1 23.5 21.6 LON (deg W) 25.2 26.5 27.8 28.1 27.5 27.3 28.7 29.2 29.8 30.8 30.4 30.9 32.4 DTL (km) 830 979 1119 1158 1108 1095 1219 1264 1328 1439 1422 1447 1599 TRACK SOURCE AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 TABM TABM TABM TCGI 0-48h Genesis Forecast: 34% is 1.1 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 34% is 0.8 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 -2.8 9.4% 1.0 -0.7 9.3% VORTICITY 1.7 2.5 9.7% 1.4 1.2 10.5% VERTICAL SHEAR 16.3 28.3 8.0% 18.4 35.5 6.5% RH 73.1 73.8 -0.2% 70.9 67.1 2.1% GOES 29.1 37.6 1.6% 29.3 37.6 1.0% DVORAK 0.8 1.0 5.5% 0.8 1.0 4.8% --------------------------------------------------------------------------------------------- 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