* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * TWENTY AL202020 09/13/20 12 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 36 40 43 53 61 71 76 79 83 85 86 86 85 84 83 V (KT) LAND 30 32 36 40 43 53 61 71 76 79 83 85 86 86 85 84 83 V (KT) LGEM 30 31 33 35 37 44 52 57 57 58 59 62 65 66 66 69 72 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 9 10 10 7 6 1 4 6 10 9 12 12 12 10 14 14 17 SHEAR ADJ (KT) 0 3 4 1 0 4 5 7 4 -1 4 2 2 4 2 0 -1 SHEAR DIR 23 34 43 68 41 210 249 205 239 244 239 241 255 259 275 296 310 SST (C) 28.1 28.0 28.0 27.9 28.0 28.0 28.2 28.3 28.0 28.0 28.0 27.9 27.9 28.0 28.2 28.5 29.0 POT. INT. (KT) 138 137 137 136 137 137 139 140 136 136 136 135 135 136 139 143 151 ADJ. POT. INT. 136 135 136 134 135 135 135 133 129 127 126 123 122 123 123 126 131 200 MB T (C) -52.7 -52.1 -52.6 -52.9 -53.0 -52.5 -52.4 -52.4 -52.5 -52.4 -52.6 -52.2 -51.8 -51.5 -51.3 -51.0 -50.7 200 MB VXT (C) 0.1 0.2 0.2 0.2 0.2 0.2 0.3 0.4 0.6 0.7 0.9 1.1 1.1 1.3 1.7 1.7 1.7 TH_E DEV (C) 5 5 6 6 6 7 6 6 7 8 8 9 9 9 9 10 10 700-500 MB RH 68 69 67 67 63 63 63 61 58 55 51 51 48 47 49 50 49 MODEL VTX (KT) 20 22 24 25 25 28 30 32 32 32 34 34 36 37 37 38 39 850 MB ENV VOR 136 127 116 95 74 51 53 45 55 64 58 51 42 34 30 6 -2 200 MB DIV 105 131 116 93 79 87 87 95 66 51 61 44 38 28 2 17 -6 700-850 TADV -14 -23 -29 -14 -5 -5 -2 1 2 3 6 9 9 14 6 2 7 LAND (KM) 1728 1733 1738 1660 1588 1460 1387 1372 1418 1489 1518 1527 1447 1351 1295 1277 1275 LAT (DEG N) 12.1 12.4 12.7 13.0 13.3 13.9 14.7 15.6 16.8 18.1 19.4 20.7 22.0 xx.x xx.x xx.x xx.x LONG(DEG W) 35.9 36.9 38.0 39.1 40.2 42.5 44.6 46.1 47.5 48.8 50.0 51.1 52.4 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 10 11 11 11 11 12 10 8 9 9 9 9 8 9 8 8 8 HEAT CONTENT 11 11 11 13 13 11 17 31 28 18 18 19 28 30 24 22 26 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): 620 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 25.2 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 53.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 11.3 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. 10. 10. 11. 10. 10. 9. 9. 8. 8. 7. VERTICAL SHEAR ADJ -0. -0. -0. -0. -0. -1. -2. -3. -2. -2. -1. -1. -1. -1. -1. -1. VERTICAL SHEAR DIR 0. 1. 1. 2. 3. 2. 1. 0. -1. -2. -2. -3. -4. -3. -3. -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. -2. -3. -3. -4. -5. -5. -6. THETA_E EXCESS -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. 0. 0. 0. 1. 700-500 MB RH -0. -0. -1. -1. -1. -2. -3. -3. -3. -3. -3. -3. -3. -3. -3. -2. MODEL VTX TENDENCY 0. 2. 2. 3. 6. 8. 12. 12. 11. 13. 13. 14. 14. 13. 13. 12. 850 MB ENV VORTICITY 0. 1. 1. 1. 2. 2. 2. 2. 2. 2. 3. 3. 3. 2. 3. 2. 200 MB DIVERGENCE 0. 1. 1. 2. 2. 3. 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. -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. -1. -1. -1. -1. -2. -1. -1. -2. -2. -2. -2. -1. 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. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. ------------------------------------------------------------------------------ TOTAL CHANGE 2. 6. 10. 13. 23. 31. 41. 46. 49. 53. 55. 56. 56. 55. 54. 53. CURRENT MAX WIND (KT): 30. LAT, LON: 12.1 35.9 ** 2022 ATLANTIC RI INDEX AL202020 TWENTY 09/13/20 12 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 -49.5 to 33.0 0.60 3.4 850-200 MB SHEAR (KT) : 8.5 28.5 to 2.0 0.75 1.9 HEAT CONTENT (KJ/CM2) : 11.8 0.0 to 161.7 0.07 0.2 STD DEV OF IR BR TEMP : 25.2 36.6 to 2.8 0.34 0.7 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.3 BL DRY-AIR FLUX (W/M2) : 108.0 895.4 to -71.5 0.81 1.3 POT = MPI-VMAX (KT) : 105.0 27.0 to 140.8 0.69 0.5 2nd PC OF IR BR TEMP : -0.7 2.9 to -3.0 0.60 0.7 D200 (10**7s-1) : 104.8 -30.8 to 188.1 0.62 0.7 %area of TPW <45 mm upshear : 16.6 104.5 to 0.0 0.84 0.1 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= 10% is 1.5 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 6% is 1.5 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 5% is 2.1 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= 14% is 2.9 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 40% is 7.6 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: 3.8% 15.9% 9.9% 5.7% 5.0% 9.1% 13.5% 40.0% Logistic: 3.2% 15.5% 7.1% 1.9% 0.6% 3.9% 5.5% 5.3% Bayesian: 1.5% 1.0% 1.0% 0.0% 0.0% 0.7% 10.0% 4.8% Consensus: 2.8% 10.8% 6.0% 2.6% 1.9% 4.5% 9.7% 16.7% ## ANNULAR HURRICANE INDEX (AHI) AL202020 TWENTY 09/13/20 12 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=5 NFAIL=2 ## ## 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 12 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 36 40 43 53 61 71 76 79 83 85 86 86 85 84 83 18HR AGO 30 29 33 37 40 50 58 68 73 76 80 82 83 83 82 81 80 12HR AGO 30 27 26 30 33 43 51 61 66 69 73 75 76 76 75 74 73 6HR AGO 30 24 21 20 23 33 41 51 56 59 63 65 66 66 65 64 63 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT