* ATLANTIC TC GENESIS INDEX * * GFS VERSION * * AL932021 09/13/21 00 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 Prob of Genesis 10% 15% LAT (deg N) 17.3 17.4 17.5 17.5 17.6 17.9 18.4 18.6 17.6 16.5 15.7 15.6 16.0 LON (deg W) 28.4 29.3 29.8 30.4 30.8 31.5 32.1 33.0 34.6 36.1 37.1 37.9 39.1 DTL (km) 1196 1292 1346 1409 1452 1531 1605 1699 1856 1994 2020 1938 1881 TRACK SOURCE AEMI AEMI AEMI AEMI AEMI AEMI AEMI TABM TABM TABM TABM TABM TABM TCGI 0-48h Genesis Forecast: 10% is 0.3 times the sample mean ( 30%) TCGI 0-120h Genesis Forecast: 15% is 0.3 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 1.7 0.9% 1.0 0.3 3.3% VORTICITY 1.7 1.4 2.6% 1.4 0.2 2.4% VERTICAL SHEAR 16.3 20.2 4.7% 18.4 19.6 6.4% RH 73.1 54.7 0.0% 70.9 51.3 0.2% GOES 29.1 3.8 0.1% 29.3 3.8 0.0% DVORAK 0.8 1.0 2.2% 0.8 1.0 2.3% --------------------------------------------------------------------------------------------- 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