* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * TWENTYEIG AL282020 10/25/20 00 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 33 36 39 42 46 53 56 56 53 50 43 32 30 30 31 31 V (KT) LAND 30 33 36 39 42 46 53 56 56 53 50 34 29 28 28 28 28 V (KT) LGEM 30 32 34 37 39 41 43 44 45 46 46 32 29 N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP EXTP EXTP N/A N/A N/A N/A SHEAR (KT) 11 12 12 10 8 12 8 9 14 18 28 59 88 N/A N/A N/A N/A SHEAR ADJ (KT) 0 -2 -1 -1 0 2 0 2 1 1 0 9 -3 N/A N/A N/A N/A SHEAR DIR 276 295 306 304 266 299 296 288 240 241 196 218 221 N/A N/A N/A N/A SST (C) 30.0 29.9 29.9 29.8 29.7 29.4 28.4 28.0 27.8 26.7 25.3 25.0 22.5 N/A N/A N/A N/A POT. INT. (KT) 166 164 164 163 162 157 142 137 134 122 111 109 93 N/A N/A N/A N/A ADJ. POT. INT. 149 147 146 146 147 143 130 124 121 110 102 100 85 N/A N/A N/A N/A 200 MB T (C) -52.2 -52.6 -52.8 -52.5 -52.3 -52.6 -52.3 -52.7 -52.4 -52.7 -52.6 -52.4 -51.5 N/A N/A N/A N/A 200 MB VXT (C) 0.3 0.4 0.4 0.4 0.3 0.4 0.5 0.5 0.5 0.4 0.0 0.0 0.0 N/A N/A N/A N/A TH_E DEV (C) 8 7 7 8 8 7 8 7 8 3 1 0 0 N/A N/A N/A N/A 700-500 MB RH 75 72 67 64 61 55 55 56 57 55 52 56 48 N/A N/A N/A N/A MODEL VTX (KT) 12 11 11 13 13 13 13 11 9 8 LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 75 63 58 61 66 27 10 -14 8 40 104 174 168 N/A N/A N/A N/A 200 MB DIV 66 73 57 48 38 31 19 21 40 54 72 57 52 N/A N/A N/A N/A 700-850 TADV -1 0 1 0 0 -2 -2 -5 4 18 -53 -15 -96 N/A N/A N/A N/A LAND (KM) 342 311 279 240 202 124 38 150 368 268 29 -373 -569 N/A N/A N/A N/A LAT (DEG N) 18.9 19.2 19.4 19.7 20.0 20.7 21.6 22.9 24.6 26.7 29.8 33.7 37.5 N/A N/A N/A N/A LONG(DEG W) 83.1 83.3 83.4 83.6 83.9 85.0 86.6 88.4 89.7 90.4 89.1 86.1 83.1 N/A N/A N/A N/A STM SPEED (KT) 3 3 3 4 5 7 10 10 11 13 20 23 22 N/A N/A N/A N/A HEAT CONTENT 82 90 99 111 125 116 37 19 20 6 0 0 0 N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):345/ 2 CX,CY: 0/ 2 T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 600 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 23.3 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 68.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 26.7 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. 3. 8. 14. 19. 23. 25. 27. 27. 29. 29. 29. 28. VERTICAL SHEAR MAG 1. 2. 3. 4. 5. 6. 7. 7. 5. 3. -4. -17. -21. -23. -24. -24. VERTICAL SHEAR ADJ 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. -0. -1. -1. -1. -1. -2. -2. -1. -1. 0. 0. 0. 0. 0. PERSISTENCE 1. 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 200/250 MB TEMP. -0. -1. -1. -1. -2. -2. -2. -2. -2. -2. -3. -3. -3. -3. -2. -2. THETA_E EXCESS -0. -0. -0. -0. -0. -0. -0. -0. -1. -1. -0. -0. 0. 1. 1. 2. 700-500 MB RH -0. -0. -1. -1. -1. -2. -2. -2. -2. -2. -2. -2. -3. -3. -3. -3. MODEL VTX TENDENCY -0. -1. -0. 0. -0. -2. -4. -8. -10. -12. -12. -13. -13. -13. -13. -13. 850 MB ENV VORTICITY 0. 0. 0. 1. 1. 1. 0. 0. 0. 0. 1. 2. 2. 3. 3. 3. 200 MB DIVERGENCE 0. 0. 1. 1. 1. 0. 0. 0. 0. 0. 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. -0. -0. -0. -1. -1. -2. -2. -2. -3. -3. -3. -3. 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. 2. 2. 2. GOES PREDICTORS 0. 0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -0. -0. -0. -0. -0. OCEAN HEAT CONTENT -0. -1. -1. -2. -3. -1. 1. 1. 1. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 1. 2. 3. 5. 7. 6. 4. 2. 0. -1. -2. -3. -4. -4. -5. -4. ------------------------------------------------------------------------------ TOTAL CHANGE 3. 6. 9. 12. 16. 23. 26. 26. 23. 20. 13. 2. -0. -0. 1. 1. CURRENT MAX WIND (KT): 30. LAT, LON: 18.9 83.1 ** 2022 ATLANTIC RI INDEX AL282020 TWENTYEIG 10/25/20 00 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 4.3 850-200 MB SHEAR (KT) : 10.7 28.5 to 2.0 0.67 1.9 HEAT CONTENT (KJ/CM2) : 101.4 0.0 to 161.7 0.63 1.8 STD DEV OF IR BR TEMP : 23.3 36.6 to 2.8 0.39 1.0 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.4 BL DRY-AIR FLUX (W/M2) : 106.8 895.4 to -71.5 0.82 1.5 POT = MPI-VMAX (KT) : 116.9 27.0 to 140.8 0.79 0.7 2nd PC OF IR BR TEMP : 1.2 2.9 to -3.0 0.29 0.4 D200 (10**7s-1) : 56.4 -30.8 to 188.1 0.40 0.5 %area of TPW <45 mm upshear : 0.0 104.5 to 0.0 1.00 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 7% is 1.4 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 24% is 2.2 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 13% is 1.9 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= 7% is 3.1 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= 20% is 4.2 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 24% is 4.5 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: 6.8% 23.5% 12.7% 8.1% 7.4% 10.5% 19.6% 24.1% Logistic: 6.5% 27.9% 21.5% 12.5% 2.3% 8.6% 14.8% 22.2% Bayesian: 1.3% 1.1% 1.1% 0.5% 0.2% 0.2% 1.2% 0.3% Consensus: 4.9% 17.5% 11.8% 7.0% 3.3% 6.4% 11.9% 15.5% ## ANNULAR HURRICANE INDEX (AHI) AL282020 TWENTYEIG 10/25/20 00 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=2 NFAIL=5 ## ## 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 AL282020 TWENTYEIG 10/25/2020 00 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 33 36 39 42 46 53 56 56 53 50 34 29 28 28 28 28 18HR AGO 30 29 32 35 38 42 49 52 52 49 46 30 25 24 24 24 24 12HR AGO 30 27 26 29 32 36 43 46 46 43 40 24 19 18 18 18 18 6HR AGO 30 24 21 20 23 27 34 37 37 34 31 15 DIS DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT