* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL972020 09/13/20 06 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 33% 45% LAT (deg N) 16.6 17.1 17.5 18.0 18.8 20.4 22.0 23.6 24.9 25.8 26.5 26.8 25.5 LON (deg W) 25.8 26.9 27.3 27.8 27.8 28.0 28.5 29.1 30.0 31.2 32.6 33.5 33.4 DTL (km) 910 1036 1088 1154 1154 1145 1189 1262 1373 1512 1667 1762 1727 TRACK SOURCE AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI AEMI TABM TABM TCGI 0-48h Genesis Forecast: 33% is 1.1 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 45% is 1.1 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 -4.0 11.2% 1.0 -2.3 14.8% VORTICITY 1.7 2.2 8.7% 1.4 1.3 12.2% VERTICAL SHEAR 16.3 30.8 6.8% 18.4 29.4 10.0% RH 73.1 72.2 -0.2% 70.9 64.8 2.0% GOES 29.1 28.0 1.2% 29.3 28.0 0.8% DVORAK 0.8 1.0 5.4% 0.8 1.0 5.3% --------------------------------------------------------------------------------------------- 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