* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL972021 09/19/21 00 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 51% 66% LAT (deg N) 9.9 11.1 12.0 12.6 13.5 16.0 18.4 20.1 22.0 23.4 23.7 24.3 24.9 LON (deg W) 27.1 27.2 28.3 29.4 29.9 31.6 33.9 35.0 35.4 36.1 37.6 38.7 39.3 DTL (km) 1152 1128 1208 1307 1343 1516 1791 1875 1905 1974 2128 2241 2306 TRACK SOURCE AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 AP03 TCGI 0-48h Genesis Forecast: 51% 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 0.2 5.5% 1.0 -0.2 11.1% VORTICITY 1.7 2.2 10.9% 1.4 1.4 16.0% VERTICAL SHEAR 16.3 14.2 17.2% 18.4 18.2 19.0% RH 73.1 74.4 -0.2% 70.9 66.8 2.8% GOES 29.1 30.7 1.6% 29.3 30.7 1.1% DVORAK 0.8 2.0 16.2% 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