* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL902018 08/30/18 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 72% 90% LAT (deg N) 12.9 13.0 13.1 13.0 12.9 13.7 15.9 17.0 16.5 15.8 16.7 18.6 21.3 LON (deg W) 19.3 20.5 21.7 22.7 23.3 24.4 26.9 30.9 34.5 36.2 37.3 38.8 41.2 DTL (km) 267 381 487 591 666 750 1013 1454 1823 2010 2071 2121 2181 TRACK SOURCE TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 72% is 2.4 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 90% is 2.1 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 -3.0 14.4% 1.0 -1.0 15.0% VORTICITY 1.7 4.8 24.1% 1.4 4.1 37.4% VERTICAL SHEAR 16.3 16.6 19.5% 18.4 12.7 23.5% RH 73.1 82.3 -0.2% 70.9 78.3 3.4% GOES 29.1 95.2 6.1% 29.3 95.2 3.7% DVORAK 0.8 1.0 8.2% 0.8 1.0 7.0% --------------------------------------------------------------------------------------------- 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 2.1, February 2018