* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL972021 08/28/21 12 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 11% 29% LAT (deg N) 34.0 34.0 34.4 35.5 36.5 39.1 41.3 41.9 43.9 46.6 49.4 54.9 59.2 LON (deg W) 51.5 51.0 50.4 48.5 47.2 43.1 39.8 36.4 34.0 32.3 29.6 31.4 29.4 DTL (km) 1417 1422 1385 1302 1234 1172 1220 1431 1516 1554 1389 1391 1323 TRACK SOURCE AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 AP19 TABM TABM TCGI 0-48h Genesis Forecast: 11% is 0.4 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 29% is 0.7 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 -1.3 2.9% 1.0 -0.1 6.3% VORTICITY 1.7 1.7 3.1% 1.4 1.6 10.1% VERTICAL SHEAR 16.3 32.1 2.6% 18.4 29.6 7.2% RH 73.1 61.4 0.0% 70.9 59.9 1.1% GOES 29.1 9.9 0.2% 29.3 9.9 0.2% DVORAK 0.8 1.0 2.3% 0.8 1.0 3.9% --------------------------------------------------------------------------------------------- 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