* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL982021 09/22/21 06 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 54% 84% LAT (deg N) 8.6 8.7 8.6 8.6 8.5 8.4 9.4 10.4 11.2 13.0 14.2 15.3 16.7 LON (deg W) 31.4 33.7 34.9 35.8 36.9 40.8 43.1 45.8 47.2 48.5 49.7 50.8 51.8 DTL (km) 1594 1466 1397 1360 1312 1190 1071 930 907 991 1055 1122 1189 TRACK SOURCE AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 AP30 TCGI 0-48h Genesis Forecast: 54% is 1.8 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 84% is 2.0 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 -3.4 13.2% 1.0 -3.8 25.0% VORTICITY 1.7 2.1 10.6% 1.4 2.2 22.2% VERTICAL SHEAR 16.3 6.0 22.5% 18.4 8.7 25.8% RH 73.1 79.0 -0.2% 70.9 78.4 3.3% GOES 29.1 24.4 1.3% 29.3 24.4 0.9% DVORAK 0.8 1.0 6.9% 0.8 1.0 7.0% --------------------------------------------------------------------------------------------- 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