* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL902021 08/31/21 12 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 94% 100% LAT (deg N) 9.6 10.1 10.5 11.2 12.2 12.6 12.7 13.5 15.6 17.6 19.8 21.9 23.4 LON (deg W) 18.4 21.1 21.9 23.4 24.7 28.5 30.9 32.3 33.5 34.8 35.7 36.8 37.1 DTL (km) 337 523 586 726 829 1212 1465 1601 1718 1872 1952 2050 2076 TRACK SOURCE AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 TCGI 0-48h Genesis Forecast: 94% is 3.2 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 100% is 2.3 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 -4.3 20.2% 1.0 -2.3 19.0% VORTICITY 1.7 4.9 28.0% 1.4 5.2 44.4% VERTICAL SHEAR 16.3 10.4 27.0% 18.4 16.4 20.6% RH 73.1 87.8 -0.2% 70.9 81.6 2.7% GOES 29.1 43.2 3.2% 29.3 43.2 1.6% DVORAK 0.8 1.5 16.1% 0.8 1.5 11.7% --------------------------------------------------------------------------------------------- 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