* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL952021 08/12/21 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 29% 47% LAT (deg N) 13.0 13.9 14.0 14.1 14.5 15.3 16.4 15.6 15.5 15.2 15.2 15.6 16.1 LON (deg W) 42.7 44.4 46.3 47.5 48.9 52.2 56.3 61.6 64.6 67.5 70.6 73.5 76.2 DTL (km) 1370 1331 1212 1150 1122 1075 803 529 309 307 277 268 186 TRACK SOURCE AP22 AP22 AP22 AP22 AP22 AP22 AP22 AP22 TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 29% is 1.0 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 47% 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 0.7 3.4% 1.0 -0.4 9.7% VORTICITY 1.7 1.4 5.9% 1.4 1.0 10.7% VERTICAL SHEAR 16.3 9.3 14.8% 18.4 13.7 17.8% RH 73.1 72.2 -0.1% 70.9 73.7 3.1% GOES 29.1 9.8 0.4% 29.3 9.8 0.3% DVORAK 0.8 1.0 5.0% 0.8 1.0 5.5% --------------------------------------------------------------------------------------------- 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