* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL922021 08/08/21 06 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 16% 23% LAT (deg N) 13.6 14.6 15.2 15.5 15.7 16.3 16.5 16.7 16.7 16.9 17.3 18.5 20.3 LON (deg W) 26.9 27.3 27.9 28.9 29.7 32.0 35.0 38.2 41.4 44.1 46.8 49.3 51.3 DTL (km) 1021 1053 1117 1225 1311 1565 1878 2000 1776 1605 1494 1510 1474 TRACK SOURCE AP11 AP11 AP11 AP11 TABM TABM TABM TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 16% is 0.5 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 23% is 0.5 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 2.9 0.1% 1.0 1.9 1.9% VORTICITY 1.7 1.4 3.6% 1.4 0.5 4.4% VERTICAL SHEAR 16.3 19.5 6.6% 18.4 16.9 9.6% RH 73.1 70.8 -0.1% 70.9 66.0 1.3% GOES 29.1 7.9 0.2% 29.3 7.9 0.1% DVORAK 0.8 1.5 5.2% 0.8 1.5 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