* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * SAM AL182021 09/24/21 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 65 70 77 83 89 96 102 104 108 109 108 108 107 106 107 106 101 V (KT) LAND 65 70 77 83 89 96 102 104 108 109 108 108 107 106 107 106 101 V (KT) LGEM 65 69 75 81 87 98 106 109 108 105 102 100 98 96 93 88 81 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 3 4 5 4 2 6 8 7 12 11 11 7 12 11 18 16 18 SHEAR ADJ (KT) 0 -3 -4 0 1 -2 -3 -3 -4 -6 -6 -5 -1 0 0 6 7 SHEAR DIR 336 51 76 57 26 6 320 325 288 305 276 263 244 235 238 230 228 SST (C) 28.3 28.6 28.9 28.8 28.6 28.5 28.7 28.6 28.5 28.6 28.6 28.7 28.8 28.8 28.8 28.7 29.1 POT. INT. (KT) 141 146 150 148 144 143 146 144 143 145 145 146 148 149 149 148 154 ADJ. POT. INT. 141 145 149 145 140 137 140 137 136 138 137 136 138 140 141 139 143 200 MB T (C) -53.5 -53.2 -53.5 -53.8 -53.7 -53.6 -53.9 -53.7 -54.1 -53.9 -53.9 -53.6 -53.6 -53.3 -53.3 -53.2 -52.9 200 MB VXT (C) -0.1 0.0 0.1 0.1 0.1 0.2 0.2 0.3 0.3 0.5 0.7 0.7 0.8 0.8 0.8 0.8 0.9 TH_E DEV (C) 9 9 9 9 9 9 9 9 9 10 10 10 9 9 9 9 7 700-500 MB RH 56 58 57 56 54 58 56 53 50 51 48 50 50 53 56 64 66 MODEL VTX (KT) 16 18 18 18 20 19 21 21 24 26 26 27 29 29 32 34 34 850 MB ENV VOR 1 -3 -8 -18 -29 -28 -30 -30 -31 -20 -27 -24 -19 1 11 34 41 200 MB DIV 52 74 71 44 19 49 44 52 65 45 36 68 52 87 80 92 74 700-850 TADV 0 0 -1 -2 -1 -1 -1 1 4 3 3 4 0 5 11 17 17 LAND (KM) 1228 1166 1112 1072 1031 988 960 966 1018 993 922 898 876 693 522 498 651 LAT (DEG N) 11.6 11.8 12.0 12.2 12.4 12.8 13.2 13.8 14.6 15.5 16.5 17.4 18.3 xx.x xx.x xx.x xx.x LONG(DEG W) 43.1 44.1 45.2 46.0 46.9 48.2 49.6 50.8 51.8 53.2 54.8 56.2 57.4 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 11 10 9 9 8 7 7 6 7 9 9 8 8 11 12 13 13 HEAT CONTENT 18 19 24 25 24 27 42 41 43 52 40 42 51 52 43 36 68 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 13 CX,CY: -12/ 2 T-12 MAX WIND: 60 PRESSURE OF STEERING LEVEL (MB): 568 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 8.0 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 96.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 31.2 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. 3. 4. 5. 5. 5. 5. 6. 7. 7. 8. 8. 7. 7. 6. 5. VERTICAL SHEAR MAG 1. 1. 2. 3. 5. 7. 9. 10. 11. 12. 13. 13. 14. 14. 14. 13. VERTICAL SHEAR ADJ 0. 1. 1. 1. 1. 2. 3. 4. 4. 4. 4. 4. 3. 3. 2. 1. VERTICAL SHEAR DIR 0. 1. 1. 2. 3. 4. 4. 4. 3. 2. 2. 1. -0. -1. -1. -2. PERSISTENCE 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. -0. -0. 0. 0. 0. 0. 200/250 MB TEMP. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. -0. -0. -0. 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. -0. -0. -1. -1. -1. -1. -0. -0. -0. -1. -1. -1. MODEL VTX TENDENCY 0. 0. 1. 1. 1. 3. 2. 6. 7. 8. 9. 9. 9. 11. 13. 11. 850 MB ENV VORTICITY -0. -0. -0. -1. -1. -2. -2. -2. -3. -3. -3. -4. -4. -4. -4. -4. 200 MB DIVERGENCE 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 0. -0. -1. -1. -2. -2. 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. 0. 0. 0. 0. 0. 0. 1. 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 1. 1. 2. 2. 1. 1. 2. 2. 1. 1. 1. 2. 2. 3. 3. 2. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 1. 2. 4. 6. 8. 8. 5. 3. 1. -1. -3. -5. -5. -5. -6. -6. ------------------------------------------------------------------------------ TOTAL CHANGE 5. 12. 18. 24. 31. 37. 39. 43. 44. 43. 43. 42. 41. 42. 41. 36. CURRENT MAX WIND (KT): 65. LAT, LON: 11.6 43.1 ** 2021 ATLANTIC RI INDEX AL182021 SAM 09/24/21 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) : 5.0 -49.5 to 33.0 0.66 8.0 850-200 MB SHEAR (KT) : 3.6 30.1 to 2.3 0.95 5.4 HEAT CONTENT (KJ/CM2) : 22.0 0.0 to 151.8 0.14 0.7 STD DEV OF IR BR TEMP : 8.0 36.6 to 2.8 0.85 4.9 MAXIMUM WIND (KT) : 65.0 22.5 to 137.5 0.95 4.4 BL DRY-AIR FLUX (W/M2) : 384.2 895.4 to -55.0 0.54 2.5 2nd PC OF IR BR TEMP : 0.1 2.9 to -2.9 0.49 1.6 POT = MPI-VMAX (KT) : 79.1 28.3 to 146.3 0.43 0.9 D200 (10**7s-1) : 52.0 -29.7 to 185.9 0.38 0.7 %area of TPW <45 mm upshear : 10.5 100.0 to 0.0 0.89 0.4 SHIPS Prob RI for 20kt/ 12hr RI threshold= 14% is 2.9 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 41% is 3.8 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 30% is 4.4 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 23% is 5.9 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 20% is 8.4 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 28% is 6.0 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 25% is 5.3 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 16% is 3.0 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: 14.3% 40.9% 29.7% 23.1% 20.2% 27.7% 24.7% 15.7% Logistic: 12.6% 41.4% 31.6% 19.6% 10.7% 22.7% 14.9% 7.9% Bayesian: 6.1% 44.1% 32.2% 2.9% 2.7% 19.7% 16.6% 0.7% Consensus: 11.0% 42.1% 31.1% 15.2% 11.2% 23.4% 18.8% 8.1% DTOPS: 31.0% 65.0% 43.0% 30.0% 13.0% 25.0% 17.0% 16.0% ## ANNULAR HURRICANE INDEX (AHI) AL182021 SAM 09/24/21 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 09/24/2021 12 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 2 6( 8) 11( 18) 19( 34) <-- PROB BASED ON INTENSITY ONLY PROB(%) 0 1( 1) 2( 3) 5( 8) <-- 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) 65 70 77 83 89 96 102 104 108 109 108 108 107 106 107 106 101 18HR AGO 65 64 71 77 83 90 96 98 102 103 102 102 101 100 101 100 95 12HR AGO 65 62 61 67 73 80 86 88 92 93 92 92 91 90 91 90 85 6HR AGO 65 59 56 55 61 68 74 76 80 81 80 80 79 78 79 78 73 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT