* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL922020 09/06/20 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 78% 95% LAT (deg N) 17.9 17.6 17.2 16.9 16.5 15.9 16.3 17.7 19.4 20.4 20.5 20.3 20.6 LON (deg W) 39.7 41.3 42.4 43.2 43.7 43.7 43.4 43.7 45.2 47.3 49.0 49.9 49.8 DTL (km) 1997 1858 1753 1670 1607 1552 1605 1705 1790 1786 1677 1593 1617 TRACK SOURCE TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 78% is 2.6 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 95% is 2.2 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 8.1% 1.0 -0.8 14.0% VORTICITY 1.7 4.3 23.0% 1.4 4.1 37.4% VERTICAL SHEAR 16.3 8.9 25.6% 18.4 14.4 22.5% RH 73.1 77.0 -0.3% 70.9 76.7 3.7% GOES 29.1 9.4 0.6% 29.3 9.4 0.4% DVORAK 0.8 2.0 20.6% 0.8 2.0 17.1% --------------------------------------------------------------------------------------------- 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