* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL952020 09/12/20 12 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 55% 76% LAT (deg N) 11.7 11.9 12.2 12.4 12.7 12.3 14.9 15.7 17.6 19.9 21.3 22.8 23.8 LON (deg W) 30.5 31.3 31.9 32.5 32.9 34.7 34.6 35.0 34.5 34.4 35.0 36.8 38.9 DTL (km) 1447 1526 1582 1641 1678 1788 1836 1878 1840 1815 1865 2043 2260 TRACK SOURCE AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 AP14 TCGI 0-48h Genesis Forecast: 55% is 1.8 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 76% is 1.8 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 -3.2 12.7% 1.0 -2.3 19.2% VORTICITY 1.7 3.3 15.1% 1.4 2.8 26.7% VERTICAL SHEAR 16.3 12.4 18.9% 18.4 18.7 19.2% RH 73.1 79.1 -0.2% 70.9 68.5 3.1% GOES 29.1 19.3 1.0% 29.3 19.3 0.7% DVORAK 0.8 1.0 7.0% 0.8 1.0 6.8% --------------------------------------------------------------------------------------------- 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