* ATLANTIC TC GENESIS INDEX * * AL992015 09/27/15 18 UTC * TIME (hr) 0 6 12 18 24 36 48 60 72 84 96 108 120 TCGI (%) 17.6 17.6 HDIV (x10-7s-1) -2.0 0.0 0.0 -5.0 -4.0 -2.0 -2.0 -1.0 -2.0 3.0 -2.0 1.0 -1.0 VORT (x10-6s-1) 1.6 1.4 1.0 0.9 1.3 1.2 1.5 1.5 1.7 1.7 2.0 1.3 0.8 DV24 (x10-6s-1) -0.3 -0.1 0.2 0.3 0.2 0.3 0.2 0.2 0.3 -0.4 -1.2 -1.9 -1.3 VSHD (kt) 25 29 32 31 25 34 39 42 43 54 64 83 97 MLRH (%) 77 74 72 77 82 80 82 81 78 74 78 74 64 PCCD (%) 23 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A TNUM 0.50 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A LAT (deg N) 22.2 23.3 24.4 25.6 26.9 29.3 31.4 32.5 33.3 34.3 35.7 37.4 38.7 LON (deg W) 88.0 87.6 87.2 86.8 86.4 85.5 84.1 81.8 79.4 77.1 75.3 74.2 74.3 DTL (km) 70 189 314 436 326 42 -142 -95 -7 40 54 121 63 TRACK SOURCE BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG BAMG Prob of Genesis (t= 48h) = 17.6 is 0.6 times the sample mean ( 27.9) Prob of Genesis (t=120h) = 17.6 is 0.4 times the sample mean ( 40.3) --------------------------------------------------------------------------------------------- CONTRIBUTIONS OF CLIMATOLOGY AND INDIVIDUAL PREDICTORS TO TCGI PROBABILITY ******* 48-HR ****** ******* 120-HR ****** AVG FCST %CONT AVG FCST %CONT CLIM (%) 27.9 N/A HDIV (x10-7s-1) -1.3 -2.0 3.1 -1.3 -2.0 3.1 DV24 (x10-6s-1) -0.2 0.1 4.6 -0.2 0.1 4.6 VSHD (kt) 16.8 31.0 -10.8 16.8 31.0 -10.8 MLRH (%) 64.9 78.3 -0.2 64.9 78.3 -0.2 PCCD (%) 29.1 23.2 -1.0 29.1 23.2 -1.0 TNUM 0.9 0.5 -6.0 0.9 0.5 -6.0 %CONT = % contribution to TCGI probability --------------------------------------------------------------------------------------------- PREDICTOR DEFINITIONS (Averaged Over 500 km Radius) CLIM = Climatological Probability of Genesis (Source: NHC-TAFB Invest Database) HDIV = 850-mb GFS Horizontal Divergence DV24 = 24-hr Change in GFS 850-mb Vorticity (VORT) VSHD = 850-200 mb GFS Vertical Shear MLRH = 600-mb GFS Relative Humidity PCCD = % GOES WV Pixels Colder Than -40C TNUM = TAFB T-Number