* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * SAM AL182021 09/23/21 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 40 45 50 56 61 71 78 84 89 90 95 97 95 100 98 102 101 V (KT) LAND 40 45 50 56 61 71 78 84 89 90 95 97 95 100 98 102 101 V (KT) LGEM 40 45 50 56 62 75 83 87 86 85 85 86 88 89 88 85 85 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 3 3 1 1 3 4 9 4 11 6 10 4 12 9 10 12 13 SHEAR ADJ (KT) 0 -2 -2 -1 0 0 0 0 0 2 -3 -1 -4 -2 3 0 4 SHEAR DIR 318 311 19 188 251 207 256 209 257 244 200 210 221 220 236 209 218 SST (C) 28.6 28.5 28.6 28.7 28.7 28.7 28.4 28.4 28.4 28.3 28.3 28.2 28.3 28.6 28.7 28.6 28.7 POT. INT. (KT) 147 145 146 148 148 147 142 142 141 140 140 139 141 145 146 145 148 ADJ. POT. INT. 147 145 146 148 148 145 138 136 133 132 133 132 132 135 136 135 137 200 MB T (C) -53.6 -53.5 -53.7 -54.0 -54.1 -54.0 -54.0 -53.7 -54.1 -53.8 -53.8 -53.5 -53.6 -53.4 -53.5 -53.2 -53.7 200 MB VXT (C) -0.1 -0.1 -0.1 -0.1 0.0 0.0 0.0 0.0 0.2 0.3 0.4 0.5 0.7 0.8 1.0 0.9 0.8 TH_E DEV (C) 8 8 9 8 8 9 9 9 9 10 9 10 10 10 9 9 8 700-500 MB RH 62 61 62 62 59 56 56 56 51 49 46 48 47 48 50 53 59 MODEL VTX (KT) 10 10 11 12 14 17 18 20 21 21 24 25 24 29 28 32 32 850 MB ENV VOR 13 9 6 1 -2 -21 -32 -31 -21 -21 -15 -14 -25 -21 -27 3 22 200 MB DIV 1 7 13 33 48 58 41 82 57 67 76 47 10 39 32 49 42 700-850 TADV 4 3 0 0 0 0 0 1 -1 4 7 5 6 7 7 14 8 LAND (KM) 1549 1556 1480 1385 1299 1196 1124 1076 1093 1095 1126 1037 1011 960 798 665 616 LAT (DEG N) 10.8 11.1 11.3 11.6 11.8 12.5 13.0 13.6 14.3 14.9 15.6 16.5 17.8 xx.x xx.x xx.x xx.x LONG(DEG W) 37.4 38.6 39.9 41.1 42.4 44.6 46.3 48.0 49.1 50.4 51.8 53.4 55.0 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 13 13 12 12 12 10 9 8 7 7 8 9 9 9 9 10 12 HEAT CONTENT 23 17 15 17 19 19 20 27 40 43 52 37 32 51 59 47 32 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 14 CX,CY: -13/ 2 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 572 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 15.8 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 76.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 29.4 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 1. 1. 2. 3. 4. 8. 13. 16. 20. 22. 24. 26. 28. 28. 28. 27. VERTICAL SHEAR MAG 1. 2. 4. 5. 7. 9. 11. 12. 13. 14. 14. 14. 14. 14. 14. 14. VERTICAL SHEAR ADJ 0. 0. 1. 1. 1. 2. 2. 2. 2. 2. 2. 2. 2. 2. 2. 1. VERTICAL SHEAR DIR -0. 0. -0. -0. -1. -2. -4. -5. -6. -7. -7. -8. -10. -10. -9. -9. PERSISTENCE 2. 2. 3. 2. 1. 1. 1. 1. 0. 1. 0. 0. 0. 1. 2. 2. 200/250 MB TEMP. -0. -1. -1. -1. -1. -0. -0. -0. -0. -0. -0. -0. 0. 0. 1. 1. THETA_E EXCESS 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. 700-500 MB RH -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. MODEL VTX TENDENCY -0. 0. 1. 2. 4. 6. 9. 11. 11. 14. 15. 13. 17. 14. 17. 17. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -2. -2. -2. -2. -3. -3. -3. -4. -4. -4. 200 MB DIVERGENCE -0. -0. -0. -0. -0. 0. 0. 1. 1. 1. 0. -0. -0. -0. -1. -1. 850-700 T ADVEC -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. 0. 0. 0. ZONAL STORM MOTION -0. -0. 0. 0. 1. 1. 1. 1. 2. 2. 3. 3. 3. 3. 3. 3. STEERING LEVEL PRES 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 0. 0. 0. 0. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. GOES PREDICTORS 0. 1. 1. 1. 1. 0. 0. 0. -0. -0. -0. 0. 0. 1. 1. 1. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 1. 2. 4. 5. 8. 7. 5. 3. 0. -1. -3. -4. -5. -5. -5. -5. ------------------------------------------------------------------------------ TOTAL CHANGE 5. 10. 16. 21. 31. 38. 44. 49. 50. 55. 57. 55. 60. 58. 62. 61. CURRENT MAX WIND (KT): 40. LAT, LON: 10.8 37.4 ** 2022 ATLANTIC RI INDEX AL182021 SAM 09/23/21 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) : 10.0 -45.0 to 30.0 0.73 8.1 850-200 MB SHEAR (KT) : 2.2 25.9 to 2.2 1.00 5.1 HEAT CONTENT (KJ/CM2) : 18.2 0.0 to 147.0 0.12 0.6 STD DEV OF IR BR TEMP : 15.8 33.3 to 3.1 0.58 2.4 MAXIMUM WIND (KT) : 40.0 25.0 to 125.0 0.42 1.5 2nd PC OF IR BR TEMP : -0.1 2.6 to -2.7 0.51 1.2 BL DRY-AIR FLUX (W/M2) : 196.8 814.0 to -65.0 0.70 2.1 POT = MPI-VMAX (KT) : 106.7 30.0 to 128.0 0.78 1.2 D200 (10**7s-1) : 20.4 -28.0 to 171.0 0.24 0.5 %area of TPW <45 mm upshear : 8.6 95.0 to 0.0 0.91 0.4 SHIPS Prob RI for 20kt/ 12hr RI threshold= 8% is 1.6 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 33% is 3.1 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 23% is 3.4 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 12% is 3.0 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 7% is 2.7 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 23% is 5.1 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 28% is 6.0 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 47% is 8.9 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: 7.9% 33.4% 23.1% 11.7% 6.6% 23.3% 28.0% 46.9% Logistic: 11.7% 48.9% 38.1% 19.6% 9.1% 32.8% 30.2% 22.3% Bayesian: 5.3% 51.1% 23.0% 1.2% 1.6% 14.9% 28.0% 6.1% Consensus: 8.3% 44.5% 28.1% 10.8% 5.8% 23.6% 28.7% 25.1% ## ANNULAR HURRICANE INDEX (AHI) AL182021 SAM 09/23/21 12 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 AL182021 SAM 09/23/2021 12 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 0 0( 0) 0( 0) 4( 4) <-- 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) 40 45 50 56 61 71 78 84 89 90 95 97 95 100 98 102 101 18HR AGO 40 39 44 50 55 65 72 78 83 84 89 91 89 94 92 96 95 12HR AGO 40 37 36 42 47 57 64 70 75 76 81 83 81 86 84 88 87 6HR AGO 40 34 31 30 35 45 52 58 63 64 69 71 69 74 72 76 75 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT