* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * TWENTY AL202020 09/13/20 18 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 53 64 69 76 79 86 88 89 89 87 88 85 V (KT) LAND 30 32 35 38 43 53 64 69 76 79 86 88 89 89 87 88 85 V (KT) LGEM 30 31 32 34 37 46 55 59 59 61 64 67 69 70 72 76 79 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 9 7 4 4 3 2 5 8 8 13 11 9 10 12 12 13 13 SHEAR ADJ (KT) 1 3 4 0 -1 3 6 6 4 2 1 3 0 0 -2 0 -3 SHEAR DIR 32 40 57 23 128 290 228 212 256 244 240 253 228 249 280 304 323 SST (C) 28.0 28.0 27.9 28.0 28.1 28.1 28.4 28.3 28.1 28.2 28.2 28.0 28.1 28.1 28.5 29.0 29.1 POT. INT. (KT) 137 137 136 138 139 138 142 141 138 139 139 136 138 137 143 151 153 ADJ. POT. INT. 135 136 135 137 137 134 137 134 130 130 130 124 124 123 127 133 132 200 MB T (C) -52.3 -52.5 -52.9 -53.1 -52.6 -52.9 -52.0 -52.6 -52.2 -52.5 -51.8 -52.1 -51.1 -51.4 -50.5 -50.8 -49.7 200 MB VXT (C) 0.1 0.2 0.2 0.2 0.1 0.2 0.3 0.5 0.7 0.9 1.2 1.2 0.9 1.5 1.5 2.1 1.5 TH_E DEV (C) 5 6 6 6 7 7 7 7 8 8 9 9 9 9 10 10 11 700-500 MB RH 69 67 66 62 60 64 63 60 57 52 49 47 45 46 46 48 47 MODEL VTX (KT) 20 22 22 22 23 28 32 30 32 31 34 35 36 36 36 38 37 850 MB ENV VOR 124 114 99 80 58 53 48 45 67 65 62 58 49 39 26 11 4 200 MB DIV 122 118 97 84 87 90 98 50 30 35 64 32 44 -8 27 -4 40 700-850 TADV -19 -22 -14 -4 -2 -6 -1 1 1 6 7 10 14 12 9 4 5 LAND (KM) 1743 1731 1650 1564 1486 1376 1319 1328 1383 1427 1420 1379 1303 1236 1212 1205 1242 LAT (DEG N) 12.5 12.8 13.1 13.4 13.6 14.1 14.9 15.9 17.1 18.4 19.8 21.3 22.7 xx.x xx.x xx.x xx.x LONG(DEG W) 37.0 38.1 39.3 40.5 41.8 44.0 45.9 47.5 48.9 50.3 51.6 52.9 54.1 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 11 12 12 12 12 10 10 9 9 9 10 9 9 8 8 8 8 HEAT CONTENT 11 12 13 13 12 14 29 41 22 20 25 35 38 24 22 27 30 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):290/ 10 CX,CY: -8/ 3 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 614 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 28.1 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 58.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 12.1 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. 9. 14. 19. 23. 26. 28. 30. 32. 32. 33. 32. VERTICAL SHEAR MAG 1. 2. 3. 4. 7. 9. 11. 12. 12. 11. 11. 11. 11. 10. 10. 10. VERTICAL SHEAR ADJ -0. -0. -0. -0. -1. -1. -2. -3. -2. -2. -2. -1. -1. -1. -0. -0. VERTICAL SHEAR DIR 0. 1. 1. 2. 2. 1. 0. -1. -2. -2. -3. -4. -4. -4. -4. -3. 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. -3. -3. -4. -4. -5. -6. -7. THETA_E EXCESS -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -0. -0. 0. 0. 0. 0. 700-500 MB RH -0. -0. -1. -1. -1. -2. -2. -3. -3. -3. -2. -2. -2. -2. -1. -1. MODEL VTX TENDENCY 0. 0. 0. 1. 5. 10. 8. 11. 10. 14. 14. 13. 13. 11. 12. 10. 850 MB ENV VORTICITY 0. 1. 1. 1. 1. 2. 2. 2. 2. 2. 3. 3. 3. 3. 3. 2. 200 MB DIVERGENCE 0. 1. 1. 2. 2. 3. 3. 3. 2. 2. 1. -0. -1. -1. -1. -2. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -1. -1. -0. -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. 1. STEERING LEVEL PRES 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -1. -1. GOES PREDICTORS -0. -0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 0. 0. 1. 1. 1. 1. 0. 0. 0. -0. -0. -0. 0. 0. 0. 0. ------------------------------------------------------------------------------ TOTAL CHANGE 2. 5. 8. 13. 23. 34. 39. 46. 49. 56. 58. 59. 59. 57. 58. 55. CURRENT MAX WIND (KT): 30. LAT, LON: 12.5 37.0 ** 2022 ATLANTIC RI INDEX AL202020 TWENTY 09/13/20 18 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 3.6 850-200 MB SHEAR (KT) : 5.4 25.9 to 2.2 0.86 2.4 HEAT CONTENT (KJ/CM2) : 12.2 0.0 to 147.0 0.08 0.2 STD DEV OF IR BR TEMP : 28.1 33.3 to 3.1 0.17 0.4 MAXIMUM WIND (KT) : 30.0 25.0 to 125.0 0.14 0.3 2nd PC OF IR BR TEMP : -0.8 2.6 to -2.7 0.64 0.9 BL DRY-AIR FLUX (W/M2) : 117.4 814.0 to -65.0 0.79 1.3 POT = MPI-VMAX (KT) : 106.0 30.0 to 128.0 0.78 0.6 D200 (10**7s-1) : 101.6 -28.0 to 171.0 0.65 0.7 %area of TPW <45 mm upshear : 8.3 95.0 to 0.0 0.91 0.2 SHIPS Prob RI for 20kt/ 12hr RI threshold= 4% is 0.8 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 16% 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= 6% is 1.6 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 3% is 1.4 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 9% is 2.0 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 16% is 3.3 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 38% is 7.3 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: 3.9% 16.2% 10.6% 6.4% 3.4% 9.3% 15.5% 38.5% Logistic: 3.2% 15.6% 7.5% 1.7% 0.5% 2.8% 4.2% 5.3% Bayesian: 1.7% 1.2% 1.3% 0.0% 0.0% 0.9% 7.1% 4.6% Consensus: 2.9% 11.0% 6.5% 2.7% 1.3% 4.3% 9.0% 16.1% ## ANNULAR HURRICANE INDEX (AHI) AL202020 TWENTY 09/13/20 18 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=4 NFAIL=3 ## ## 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 18 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 53 64 69 76 79 86 88 89 89 87 88 85 18HR AGO 30 29 32 35 40 50 61 66 73 76 83 85 86 86 84 85 82 12HR AGO 30 27 26 29 34 44 55 60 67 70 77 79 80 80 78 79 76 6HR AGO 30 24 21 20 25 35 46 51 58 61 68 70 71 71 69 70 67 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT