* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * TWENTY AL202020 09/13/20 06 UTC * TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168 V (KT) NO LAND 30 32 35 38 43 52 63 70 74 77 78 84 84 86 82 82 83 V (KT) LAND 30 32 35 38 43 52 63 70 74 77 78 84 84 86 82 82 83 V (KT) LGEM 30 31 33 35 37 44 53 59 62 61 60 61 62 63 64 66 69 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 6 9 9 10 8 5 3 6 13 10 13 12 17 15 18 15 18 SHEAR ADJ (KT) 0 1 4 2 0 -3 4 9 5 4 2 3 1 1 -2 -1 1 SHEAR DIR 44 23 33 37 30 71 202 202 207 227 230 234 253 249 254 243 252 SST (C) 28.0 28.1 28.1 28.0 27.9 28.1 28.0 28.3 28.0 27.9 27.9 27.9 27.9 27.9 28.2 28.5 28.9 POT. INT. (KT) 136 138 138 137 136 139 137 141 137 135 135 135 135 135 139 144 150 ADJ. POT. INT. 134 135 135 135 134 137 133 135 130 126 125 123 122 121 125 127 132 200 MB T (C) -52.8 -52.7 -52.2 -52.7 -53.0 -52.6 -52.8 -52.1 -52.7 -52.2 -52.5 -52.0 -51.9 -51.4 -51.8 -51.4 -51.8 200 MB VXT (C) 0.1 0.1 0.1 0.2 0.2 0.2 0.4 0.4 0.5 0.5 0.7 1.1 1.3 1.3 1.6 1.1 1.9 TH_E DEV (C) 5 5 5 6 6 7 7 7 7 8 9 9 9 10 10 10 10 700-500 MB RH 71 70 70 67 66 62 62 60 57 54 48 43 41 39 39 39 43 MODEL VTX (KT) 18 19 21 22 24 25 28 28 28 28 27 31 31 34 32 33 34 850 MB ENV VOR 136 138 119 117 96 52 47 51 57 79 78 65 49 46 27 7 4 200 MB DIV 73 102 119 111 96 88 83 90 51 49 36 59 13 25 -7 30 16 700-850 TADV -4 -16 -22 -23 -18 -4 -6 -1 2 5 6 10 11 14 12 3 10 LAND (KM) 1742 1746 1756 1755 1682 1539 1444 1395 1426 1491 1554 1564 1520 1445 1382 1351 1352 LAT (DEG N) 12.0 12.3 12.6 12.9 13.2 13.8 14.5 15.4 16.6 17.9 19.3 20.7 22.1 xx.x xx.x xx.x xx.x LONG(DEG W) 35.1 36.0 36.9 37.9 39.0 41.3 43.5 45.4 46.9 48.3 49.5 50.6 51.7 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 9 9 10 11 11 12 10 10 10 9 9 8 9 9 10 10 10 HEAT CONTENT 9 11 11 12 13 12 12 22 29 18 17 17 24 24 29 22 25 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):285/ 9 CX,CY: -8/ 2 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 637 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 21.3 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 35.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 8.8 INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168 ------------------------------------------------------------------------------ SAMPLE MEAN CHANGE 1. 2. 3. 4. 6. 8. 9. 10. 11. 12. 12. 13. 14. 15. 15. 16. SST POTENTIAL 0. 1. 1. 2. 4. 8. 14. 19. 23. 26. 28. 30. 32. 32. 32. 31. VERTICAL SHEAR MAG 1. 2. 3. 4. 6. 8. 9. 10. 9. 9. 8. 7. 6. 5. 4. 4. VERTICAL SHEAR ADJ 0. -0. -0. -0. 0. 0. -1. -2. -2. -1. -1. -1. -1. -1. -0. -0. VERTICAL SHEAR DIR 0. 1. 1. 2. 4. 4. 4. 3. 2. 1. 0. -0. -1. -1. -1. -1. PERSISTENCE -0. -1. -1. -1. -0. -0. -0. -0. -0. 0. 0. 0. -0. -0. -1. -0. 200/250 MB TEMP. -0. -1. -1. -1. -2. -2. -2. -2. -2. -2. -3. -3. -4. -4. -5. -6. THETA_E EXCESS -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. 0. 0. 0. 0. 700-500 MB RH -0. -0. -1. -1. -2. -2. -3. -3. -3. -3. -3. -2. -2. -1. -1. -0. MODEL VTX TENDENCY 0. 1. 2. 4. 5. 9. 10. 9. 9. 7. 11. 11. 13. 9. 9. 10. 850 MB ENV VORTICITY 0. 1. 1. 1. 2. 2. 2. 2. 3. 3. 3. 3. 3. 3. 3. 3. 200 MB DIVERGENCE 0. 1. 1. 2. 2. 2. 3. 3. 3. 2. 1. -0. -1. -1. -2. -2. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -1. -1. -1. -0. -0. -0. -0. -0. -0. -0. ZONAL STORM MOTION -0. -0. 0. 0. 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 1. 0. STEERING LEVEL PRES -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -1. -1. -0. -0. -0. -1. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -1. -1. GOES PREDICTORS -1. -1. -1. -1. -1. -2. -3. -3. -3. -3. -3. -4. -4. -4. -4. -3. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL -0. -0. -0. -0. -1. -1. -1. -0. -0. 0. 0. 1. 1. 1. 1. 1. ------------------------------------------------------------------------------ TOTAL CHANGE 2. 5. 8. 13. 22. 33. 40. 44. 47. 48. 54. 54. 56. 52. 52. 53. CURRENT MAX WIND (KT): 30. LAT, LON: 12.0 35.1 ** 2022 ATLANTIC RI INDEX AL202020 TWENTY 09/13/20 06 UTC ** (SHIPS-RII PREDICTOR TABLE for 30 KT OR MORE MAXIMUM WIND INCREASE IN NEXT 24-h) Predictor Value RI Predictor Range Scaled Value(0-1) % Contribution 12 HR PERSISTENCE (KT) : 0.0 -45.0 to 30.0 0.60 3.3 MULTI-LAYER SHEAR (KT) : 18.7 41.0 to 7.4 0.66 2.2 HEAT CONTENT (KJ/CM2) : 11.2 0.0 to 147.0 0.08 0.2 STD DEV OF IR BR TEMP : 21.3 33.3 to 3.1 0.40 0.9 MAXIMUM WIND (KT) : 30.0 25.0 to 125.0 0.14 0.3 POT = MPI-VMAX (KT) : 104.4 30.0 to 128.0 0.76 0.8 2nd PC OF IR BR TEMP : -1.4 2.6 to -2.7 0.75 1.0 D200 (10**7s-1) : 100.2 -28.0 to 171.0 0.64 0.8 BL DRY-AIR FLUX (W/M2) : 100.8 814.0 to -65.0 0.81 0.9 %area of TPW <45 mm upshear : 5.8 95.0 to 0.0 0.94 0.4 SHIPS Prob RI for 20kt/ 12hr RI threshold= 5% is 1.0 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 17% is 1.5 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 11% is 1.6 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 7% is 1.8 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 6% is 2.7 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 11% is 2.4 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 14% is 3.1 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 28% is 5.3 times climatological mean ( 5.3%) Matrix of RI probabilities ------------------------------------------------------------------------------ RI (kt / h) | 20/12 | 25/24 | 30/24 | 35/24 | 40/24 | 45/36 | 55/48 |65/72 ------------------------------------------------------------------------------ SHIPS-RII: 4.7% 16.7% 10.7% 7.1% 6.4% 10.8% 14.5% 27.9% Logistic: 3.2% 17.2% 9.0% 1.9% 0.5% 3.2% 3.4% 3.0% Bayesian: 0.6% 0.7% 0.5% 0.0% 0.0% 0.3% 6.9% 5.4% Consensus: 2.8% 11.5% 6.8% 3.0% 2.3% 4.8% 8.2% 12.1% ## ANNULAR HURRICANE INDEX (AHI) AL202020 TWENTY 09/13/20 06 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=6 NFAIL=1 ## ## AHI= 0 (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ## ** PROBLTY OF AT LEAST 1 SCNDRY EYEWL FORMTN EVENT AL202020 TWENTY 09/13/2020 06 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 0 0( 0) 0( 0) 0( 0) <-- PROB BASED ON INTENSITY ONLY PROB(%) 0 0( 0) 0( 0) 0( 0) <-- FULL MODEL PROB (RAN NORMALLY) ** DSHIPS INTENSITY FORECAST ADJUSTED RELATIVE TO ONSET OF ERC WEAKENING PHASE ** TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168 >24HR AGO (DSHIPS) 30 32 35 38 43 52 63 70 74 77 78 84 84 86 82 82 83 18HR AGO 30 29 32 35 40 49 60 67 71 74 75 81 81 83 79 79 80 12HR AGO 30 27 26 29 34 43 54 61 65 68 69 75 75 77 73 73 74 6HR AGO 30 24 21 20 25 34 45 52 56 59 60 66 66 68 64 64 65 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT