* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * EIGHTEEN AL182021 09/23/21 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 34 39 44 53 63 70 80 85 90 94 95 99 98 100 102 V (KT) LAND 30 32 34 39 44 53 63 70 80 85 90 94 95 99 98 100 102 V (KT) LGEM 30 31 33 36 39 48 55 62 67 70 75 80 83 85 86 86 86 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 2 3 3 1 2 2 5 6 4 7 6 5 7 9 12 11 14 SHEAR ADJ (KT) 1 -2 -2 -2 -2 1 0 0 0 0 0 -1 -3 -5 -1 0 3 SHEAR DIR 21 312 313 317 307 221 252 236 267 268 239 256 228 238 241 234 256 SST (C) 28.8 28.7 28.5 28.3 28.3 28.3 28.6 28.2 28.2 28.3 28.2 28.4 28.6 28.7 28.8 29.0 28.8 POT. INT. (KT) 150 148 145 142 142 141 145 139 138 140 138 142 145 147 148 152 149 ADJ. POT. INT. 150 148 145 142 142 140 143 134 133 133 131 136 138 138 139 144 139 200 MB T (C) -53.8 -53.7 -53.6 -53.8 -54.1 -53.9 -54.2 -53.6 -53.9 -53.7 -53.9 -53.4 -53.7 -53.4 -53.3 -52.9 -53.3 200 MB VXT (C) -0.1 -0.1 -0.1 -0.1 -0.1 0.0 0.0 0.0 0.1 0.3 0.4 0.5 0.7 0.9 1.1 0.9 1.0 TH_E DEV (C) 8 8 8 8 8 9 9 9 9 10 10 10 10 10 10 10 9 700-500 MB RH 64 62 61 63 62 58 58 55 55 50 49 51 50 49 49 51 55 MODEL VTX (KT) 9 9 10 11 13 14 17 18 22 22 24 25 25 28 28 30 33 850 MB ENV VOR 15 12 9 8 6 -14 -29 -38 -22 -19 -19 -14 -14 -22 -20 -12 16 200 MB DIV -9 3 10 20 43 70 50 41 69 50 64 60 31 61 31 60 39 700-850 TADV 3 4 3 0 0 0 1 3 2 4 4 6 4 7 6 4 12 LAND (KM) 1553 1535 1533 1488 1390 1236 1155 1100 1070 1080 1088 1083 977 941 887 728 591 LAT (DEG N) 10.4 10.6 10.8 11.1 11.3 11.9 12.5 13.1 13.7 14.4 15.0 15.8 16.6 xx.x xx.x xx.x xx.x LONG(DEG W) 35.7 37.1 38.4 39.6 40.9 43.3 45.2 46.8 48.3 49.6 50.9 52.4 54.2 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 13 13 13 13 12 11 9 8 8 7 7 9 9 9 10 11 12 HEAT CONTENT 28 26 18 13 15 17 23 22 31 45 47 52 39 42 58 60 29 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 13 CX,CY: -12/ 2 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 507 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 17.8 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 66.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 18.3 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. 0. 0. 1. 4. 8. 14. 19. 23. 27. 30. 33. 35. 36. 37. 36. VERTICAL SHEAR MAG 1. 2. 4. 5. 7. 10. 12. 14. 14. 15. 15. 16. 15. 15. 15. 15. 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. -8. -9. -11. -11. -10. -10. 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. -1. -0. -0. -0. -0. -0. -0. 0. 0. 1. 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. -1. -1. -1. -2. -2. -2. -2. -1. -1. -1. -1. -1. -1. MODEL VTX TENDENCY -0. -0. 0. 2. 3. 6. 8. 12. 12. 14. 15. 14. 17. 15. 16. 18. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -2. -2. -2. -2. -3. -3. -3. -3. -4. -4. 200 MB DIVERGENCE -0. -0. -1. -1. -0. 0. 0. 0. 1. 1. 0. -0. -0. -1. -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. 1. 2. 2. 2. 2. 2. 2. 2. STEERING LEVEL PRES 0. 0. 0. 1. 1. 1. 0. 1. 1. 1. 2. 2. 1. 1. 1. 1. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. GOES PREDICTORS 0. 0. 1. 0. 0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 0. 1. 2. 2. 3. 3. 2. 1. 0. -1. -1. -1. -2. -2. -2. -2. ------------------------------------------------------------------------------ TOTAL CHANGE 2. 4. 9. 14. 23. 33. 40. 50. 55. 60. 64. 65. 69. 68. 70. 72. CURRENT MAX WIND (KT): 30. LAT, LON: 10.4 35.7 ** 2021 ATLANTIC RI INDEX AL182021 EIGHTEEN 09/23/21 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 -49.5 to 33.0 0.60 2.8 850-200 MB SHEAR (KT) : 2.4 30.1 to 2.3 1.00 2.2 HEAT CONTENT (KJ/CM2) : 20.0 0.0 to 151.8 0.13 0.3 STD DEV OF IR BR TEMP : 17.8 36.6 to 2.8 0.56 1.3 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.4 BL DRY-AIR FLUX (W/M2) : 139.6 895.4 to -55.0 0.80 1.4 2nd PC OF IR BR TEMP : 0.3 2.9 to -2.9 0.45 0.6 POT = MPI-VMAX (KT) : 115.3 28.3 to 146.3 0.74 0.6 D200 (10**7s-1) : 13.4 -29.7 to 185.9 0.20 0.2 %area of TPW <45 mm upshear : 12.9 100.0 to 0.0 0.87 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 5% is 0.9 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 15% is 1.4 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= 8% is 2.1 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 6% is 2.6 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 11% is 2.3 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.6 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 27% is 5.0 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: 4.5% 15.5% 9.9% 8.4% 6.2% 10.7% 12.3% 26.8% Logistic: 6.3% 32.2% 21.8% 9.9% 4.9% 22.3% 25.4% 28.7% Bayesian: 1.2% 20.4% 7.7% 0.3% 0.4% 4.1% 5.0% 3.4% Consensus: 4.0% 22.7% 13.1% 6.2% 3.8% 12.3% 14.2% 19.6% DTOPS: 1.0% 5.0% 3.0% 1.0% 0.0% 2.0% 2.0% 16.0% ## ANNULAR HURRICANE INDEX (AHI) AL182021 EIGHTEEN 09/23/21 06 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 EIGHTEEN 09/23/2021 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 34 39 44 53 63 70 80 85 90 94 95 99 98 100 102 18HR AGO 30 29 31 36 41 50 60 67 77 82 87 91 92 96 95 97 99 12HR AGO 30 27 26 31 36 45 55 62 72 77 82 86 87 91 90 92 94 6HR AGO 30 24 21 20 25 34 44 51 61 66 71 75 76 80 79 81 83 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT