* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL912021 09/29/21 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 45% 66% LAT (deg N) 5.8 5.9 5.9 7.1 9.9 11.4 12.5 13.4 14.9 16.8 20.7 22.8 24.5 LON (deg W) 33.2 33.1 32.4 31.2 28.8 30.2 32.6 34.5 36.5 38.4 39.1 41.2 41.6 DTL (km) 1225 1241 1277 1444 1333 1425 1650 1838 2012 1996 2274 2325 2463 TRACK SOURCE AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 AP29 TCGI 0-48h Genesis Forecast: 45% is 1.5 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 66% 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 -2.0 9.3% 1.0 -1.2 14.6% VORTICITY 1.7 2.4 10.8% 1.4 2.3 22.5% VERTICAL SHEAR 16.3 11.7 17.6% 18.4 19.4 18.3% RH 73.1 76.6 -0.2% 70.9 68.9 3.1% GOES 29.1 22.4 1.1% 29.3 22.4 0.8% DVORAK 0.8 1.0 6.3% 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