* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * SAM AL182021 09/25/21 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 95 101 104 108 109 111 111 111 111 111 109 106 103 99 100 101 100 V (KT) LAND 95 101 104 108 109 111 111 111 111 111 109 106 103 99 100 101 100 V (KT) LGEM 95 102 106 107 108 108 108 107 107 105 103 100 94 86 81 78 74 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 3 6 2 1 5 5 4 4 6 6 13 14 22 20 27 26 31 SHEAR ADJ (KT) 1 -1 0 0 -1 0 0 -1 -3 0 -3 -1 1 4 5 4 13 SHEAR DIR 264 283 350 359 293 330 288 301 323 297 266 265 244 240 250 219 213 SST (C) 28.5 28.3 28.4 28.4 28.5 28.6 28.4 28.5 28.4 28.4 28.6 28.8 28.6 28.7 28.6 29.0 28.1 POT. INT. (KT) 144 140 141 141 142 144 141 143 141 141 145 148 145 147 146 154 141 ADJ. POT. INT. 142 136 136 134 135 137 133 134 132 131 135 139 135 136 135 142 128 200 MB T (C) -53.3 -53.4 -53.3 -53.6 -53.9 -53.7 -54.2 -53.7 -54.0 -53.4 -53.6 -53.3 -53.5 -53.3 -53.5 -53.2 -53.4 200 MB VXT (C) 0.1 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.4 0.4 0.7 0.7 0.7 0.8 1.0 1.1 1.0 TH_E DEV (C) 9 9 9 9 9 9 9 9 9 9 9 9 9 8 8 7 5 700-500 MB RH 58 56 57 58 58 56 52 51 50 50 51 52 56 59 63 54 33 MODEL VTX (KT) 17 18 17 20 20 22 22 23 24 27 29 30 30 30 32 36 39 850 MB ENV VOR -13 -21 -23 -19 -25 -26 -30 -30 -28 -30 -22 -20 2 14 36 64 88 200 MB DIV 26 31 37 56 48 34 23 66 57 47 37 51 68 72 55 59 77 700-850 TADV -2 -2 0 -2 -2 -1 1 4 2 4 -1 4 4 8 21 13 9 LAND (KM) 1099 1064 1037 1021 1008 1003 1034 1030 996 969 947 836 704 633 677 867 1156 LAT (DEG N) 12.7 13.0 13.2 13.4 13.5 14.0 14.7 15.5 16.4 17.3 18.0 19.1 20.5 xx.x xx.x xx.x xx.x LONG(DEG W) 46.3 47.1 48.0 48.6 49.2 50.4 51.6 52.8 53.8 55.0 56.3 57.8 59.4 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 10 9 8 6 6 7 7 7 7 7 8 10 10 11 13 15 17 HEAT CONTENT 21 20 25 32 40 44 43 50 39 33 43 56 52 30 46 51 31 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):290/ 11 CX,CY: -9/ 4 T-12 MAX WIND: 70 PRESSURE OF STEERING LEVEL (MB): 645 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 13.8 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 80.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 17.4 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. 2. 2. 2. 0. -4. -10. -14. -17. -20. -21. -23. -25. -27. -28. -28. VERTICAL SHEAR MAG 0. 1. 2. 2. 3. 6. 9. 12. 14. 15. 15. 14. 15. 15. 14. 12. VERTICAL SHEAR ADJ 0. 0. 0. 0. 1. 1. 2. 2. 2. 2. 2. 2. 2. 1. 1. 0. VERTICAL SHEAR DIR -0. -0. -0. -0. -1. -1. -2. -2. -2. -2. -3. -4. -4. -4. -4. -4. PERSISTENCE 4. 5. 4. 3. 2. 2. 2. 1. -0. -2. -3. -2. -1. 0. 1. 0. 200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -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. -0. -0. -0. -0. -0. -0. -0. -0. -0. -1. -1. -1. -1. MODEL VTX TENDENCY 0. -1. 1. 1. 2. 3. 4. 5. 8. 10. 11. 10. 8. 10. 13. 15. 850 MB ENV VORTICITY -0. -0. -1. -1. -1. -2. -2. -2. -3. -3. -3. -4. -3. -3. -3. -3. 200 MB DIVERGENCE -0. -0. 0. 0. 0. 0. 0. 1. 1. 0. 0. -0. -0. -1. -1. -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. 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. STEERING LEVEL PRES -0. -0. -0. -0. -0. -0. -0. -0. -0. -1. -1. -1. -1. -0. -0. -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. -0. 0. 1. 1. 2. 2. 3. 3. 3. 3. 2. 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. 1. 1. 2. 3. 3. 2. 1. 0. -0. -1. -1. -1. -1. -2. -2. ------------------------------------------------------------------------------ TOTAL CHANGE 6. 9. 13. 14. 16. 16. 16. 16. 16. 14. 11. 8. 4. 5. 6. 5. CURRENT MAX WIND (KT): 95. LAT, LON: 12.7 46.3 ** 2021 ATLANTIC RI INDEX AL182021 SAM 09/25/21 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) : 25.0 -49.5 to 33.0 0.90 9.2 850-200 MB SHEAR (KT) : 3.6 30.1 to 2.3 0.95 4.5 HEAT CONTENT (KJ/CM2) : 27.6 0.0 to 151.8 0.18 0.8 STD DEV OF IR BR TEMP : 13.8 36.6 to 2.8 0.67 3.3 MAXIMUM WIND (KT) : 95.0 22.5 to 137.5 0.55 2.2 BL DRY-AIR FLUX (W/M2) : 526.0 895.4 to -55.0 0.39 1.5 2nd PC OF IR BR TEMP : 0.7 2.9 to -2.9 0.38 1.1 POT = MPI-VMAX (KT) : 41.6 28.3 to 146.3 0.11 0.2 D200 (10**7s-1) : 39.6 -29.7 to 185.9 0.32 0.5 %area of TPW <45 mm upshear : 7.2 100.0 to 0.0 0.93 0.3 SHIPS Prob RI for 20kt/ 12hr RI threshold= 19% is 3.8 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 26% is 2.4 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 24% is 3.5 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 17% is 4.3 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 8% is 3.4 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 0% is 0.0 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 0% is 0.0 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 0% is 0.0 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: 18.5% 25.9% 23.7% 16.8% 8.2% 0.0% 0.0% 0.0% Logistic: 9.9% 22.2% 13.3% 5.1% 1.9% 8.3% 8.7% 2.5% Bayesian: 37.5% 44.7% 22.1% 2.2% 1.9% 2.4% 0.3% 0.0% Consensus: 22.0% 30.9% 19.7% 8.0% 4.0% 3.6% 3.0% 0.8% DTOPS: 39.0% 45.0% 41.0% 29.0% 9.0% 13.0% 4.0% 1.0% ## ANNULAR HURRICANE INDEX (AHI) AL182021 SAM 09/25/21 06 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=6 NFAIL=1 ## ## 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 09/25/2021 06 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 17 26( 39) 28( 56) 29( 69) <-- PROB BASED ON INTENSITY ONLY PROB(%) 4 7( 11) 28( 36) 32( 56) <-- 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) 95 101 104 108 109 111 111 111 111 111 109 106 103 99 100 101 100 18HR AGO 95 94 97 101 102 104 104 104 104 104 102 99 96 92 93 94 93 12HR AGO 95 92 91 95 96 98 98 98 98 98 96 93 90 86 87 88 87 6HR AGO 95 89 86 85 86 88 88 88 88 88 86 83 80 76 77 78 77 NOW 95 86 80 77 76 78 78 78 78 78 76 73 70 66 67 68 67 IN 6HR 95 101 92 86 83 83 83 83 83 83 81 78 75 71 72 73 72 IN 12HR 95 101 104 95 89 85 85 85 85 85 83 80 77 73 74 75 74