* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL912020 09/04/20 00 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 29% 64% LAT (deg N) 11.2 10.9 10.5 10.2 10.0 10.3 10.9 12.4 13.8 14.3 14.7 14.7 14.2 LON (deg W) 37.0 38.8 39.2 39.5 39.7 40.0 39.0 37.3 34.7 33.6 33.5 33.9 34.3 DTL (km) 1601 1534 1475 1431 1401 1411 1524 1726 1855 1732 1719 1762 1808 TRACK SOURCE AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 AP06 TCGI 0-48h Genesis Forecast: 29% is 1.0 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 64% is 1.5 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 8.7% 1.0 -1.9 17.0% VORTICITY 1.7 1.5 6.0% 1.4 1.6 16.9% VERTICAL SHEAR 16.3 23.7 8.9% 18.4 17.5 19.3% RH 73.1 74.1 -0.1% 70.9 75.7 3.6% GOES 29.1 12.1 0.5% 29.3 12.1 0.4% DVORAK 0.8 1.0 4.9% 0.8 1.0 6.6% --------------------------------------------------------------------------------------------- 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