* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL902021 09/01/21 00 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 100% 100% LAT (deg N) 11.4 12.2 12.9 13.4 13.3 11.9 10.6 13.4 17.4 16.9 17.6 20.8 21.0 LON (deg W) 21.5 23.1 25.1 27.3 29.7 34.2 35.4 35.2 39.3 43.3 43.1 45.5 49.3 DTL (km) 517 674 841 1069 1330 1767 1581 1886 1985 1670 1739 1909 1692 TRACK SOURCE TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 100% is 3.3 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 -5.7 22.7% 1.0 -4.4 22.1% VORTICITY 1.7 4.9 26.8% 1.4 5.8 40.7% VERTICAL SHEAR 16.3 9.9 26.0% 18.4 11.4 19.7% RH 73.1 82.7 -0.2% 70.9 81.0 2.3% GOES 29.1 46.5 3.2% 29.3 46.5 1.5% DVORAK 0.8 2.0 21.6% 0.8 2.0 13.8% --------------------------------------------------------------------------------------------- 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