* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL972021 09/19/21 06 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 52% 66% LAT (deg N) 11.1 12.2 13.3 14.3 15.1 17.4 20.1 22.4 23.0 23.4 23.1 22.7 22.3 LON (deg W) 27.3 27.8 28.2 28.6 29.7 32.0 33.5 33.5 33.5 35.0 37.3 38.0 38.6 DTL (km) 1138 1149 1165 1195 1310 1574 1719 1708 1707 1861 2095 2169 2233 TRACK SOURCE AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 TCGI 0-48h Genesis Forecast: 52% is 1.7 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 66% is 1.5 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 -0.6 7.1% 1.0 -0.4 11.8% VORTICITY 1.7 2.0 10.1% 1.4 1.5 16.4% VERTICAL SHEAR 16.3 14.0 17.6% 18.4 19.1 18.5% RH 73.1 75.5 -0.2% 70.9 62.0 2.1% GOES 29.1 24.8 1.3% 29.3 24.8 0.9% DVORAK 0.8 2.0 16.5% 0.8 2.0 16.1% --------------------------------------------------------------------------------------------- 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