* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL912020 09/05/20 06 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 37% 67% LAT (deg N) 11.1 11.3 11.8 12.2 13.0 14.8 16.0 16.5 16.9 17.5 18.1 19.0 19.8 LON (deg W) 37.6 37.8 37.2 36.7 35.5 33.2 31.9 31.9 32.5 33.4 34.5 36.4 38.5 DTL (km) 1578 1596 1662 1717 1835 1686 1548 1552 1620 1723 1848 2037 2238 TRACK SOURCE AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI TCGI 0-48h Genesis Forecast: 37% is 1.2 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 67% is 1.6 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 -4.4 12.9% 1.0 -2.7 19.8% VORTICITY 1.7 1.7 7.8% 1.4 1.5 16.7% VERTICAL SHEAR 16.3 17.2 13.8% 18.4 10.6 23.5% RH 73.1 79.0 -0.2% 70.9 73.9 3.8% GOES 29.1 29.4 1.4% 29.3 29.4 1.1% DVORAK 0.8 0.5 1.7% 0.8 0.5 1.9% --------------------------------------------------------------------------------------------- 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