* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/14/21 18 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 55 61 70 75 74 73 73 75 79 83 85 91 93 95 V (KT) LAND 40 45 50 55 61 70 72 50 43 44 45 49 53 55 61 63 66 V (KT) LGEM 40 43 47 51 55 65 62 43 44 47 52 61 71 81 90 96 99 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 4 4 7 10 5 7 8 13 12 16 7 6 5 8 10 15 10 SHEAR ADJ (KT) -3 -2 0 2 3 2 0 0 2 -4 1 -4 2 -3 -3 -1 0 SHEAR DIR 318 287 267 281 297 269 296 289 289 305 357 6 33 291 268 284 23 SST (C) 28.3 28.3 28.2 28.2 28.7 28.6 28.7 29.9 29.3 29.7 29.7 30.2 30.3 29.9 29.9 30.2 30.2 POT. INT. (KT) 145 143 141 141 148 146 147 168 157 165 165 172 171 166 166 170 170 ADJ. POT. INT. 145 143 140 138 145 139 140 161 149 156 154 159 156 144 141 147 146 200 MB T (C) -53.5 -53.4 -53.8 -53.9 -53.7 -53.8 -53.5 -53.3 -53.5 -53.6 -53.5 -53.4 -53.3 -53.0 -52.8 -52.4 -51.9 200 MB VXT (C) -0.1 0.1 0.3 0.3 0.2 0.2 0.4 0.4 0.2 0.3 0.2 0.4 0.4 0.5 0.5 0.9 1.0 TH_E DEV (C) 10 10 9 9 10 9 9 8 8 8 8 8 8 8 8 7 9 700-500 MB RH 58 60 61 62 66 68 67 62 63 62 64 61 66 62 67 65 70 MODEL VTX (KT) 11 11 10 10 12 13 14 13 11 11 12 13 13 13 16 17 20 850 MB ENV VOR -1 7 4 5 21 26 17 9 10 0 3 -3 0 -25 -8 -37 -37 200 MB DIV 34 44 32 55 79 67 59 14 59 24 27 1 16 2 37 6 18 700-850 TADV -11 -6 -7 -10 -9 -10 -6 -11 -9 -11 -6 -7 -7 -9 -3 -5 -1 LAND (KM) 568 496 322 177 89 46 9 0 -21 1 23 100 145 176 221 161 90 LAT (DEG N) 15.8 16.2 16.5 16.9 17.2 17.7 18.3 19.3 20.4 21.6 22.8 24.1 25.4 xx.x xx.x xx.x xx.x LONG(DEG W) 59.9 61.6 63.3 64.7 66.2 68.6 70.7 72.8 74.9 77.2 79.5 81.5 83.0 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 21 17 15 14 13 11 11 11 12 12 12 10 8 6 5 6 7 HEAT CONTENT 34 23 28 47 65 42 24 41 46 55 56 65 37 33 31 30 27 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):275/ 25 CX,CY: -24/ 2 T-12 MAX WIND: 35 PRESSURE OF STEERING LEVEL (MB): 539 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 6.2 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 99.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 36.6 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. 5. 8. 13. 17. 20. 23. 27. 30. 32. 33. 34. 33. VERTICAL SHEAR MAG 1. 2. 3. 4. 6. 7. 8. 8. 8. 8. 9. 9. 10. 9. 9. 10. VERTICAL SHEAR ADJ 0. 0. 0. 0. 0. 1. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. VERTICAL SHEAR DIR -0. -0. -1. -1. -2. -2. -3. -3. -3. -3. -3. -3. -3. -2. -2. -2. PERSISTENCE 1. 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -0. 0. -0. THETA_E EXCESS 0. 0. 0. 0. 1. 0. 0. 0. 0. 0. 0. -0. 0. 0. 0. 0. 700-500 MB RH -0. -0. -0. -0. -1. -2. -3. -3. -4. -4. -4. -5. -5. -6. -6. -6. MODEL VTX TENDENCY 0. -0. -1. 0. 1. 2. -1. -3. -4. -5. -4. -4. -5. -1. -1. 2. 850 MB ENV VORTICITY -0. -0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -2. -2. -2. -3. 200 MB DIVERGENCE 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 0. -0. -0. -0. -0. -0. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -0. -0. -0. -0. -0. -0. ZONAL STORM MOTION -0. -0. 0. 0. 1. 2. 2. 2. 4. 5. 6. 7. 7. 7. 7. 8. STEERING LEVEL PRES 0. 0. 0. 0. 1. 1. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. DAYS FROM CLIM. PEAK -0. 0. 0. 0. -0. -0. -0. -0. -0. 0. 0. 0. 0. 1. 1. 1. GOES PREDICTORS 1. 2. 2. 2. 2. 1. 1. 1. 0. 0. -0. 1. 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. 3. 5. 7. 11. 10. 7. 4. 1. -2. -4. -6. -7. -7. -8. -8. ------------------------------------------------------------------------------ TOTAL CHANGE 5. 10. 15. 21. 30. 35. 34. 33. 33. 35. 39. 43. 45. 51. 53. 55. CURRENT MAX WIND (KT): 40. LAT, LON: 15.8 59.9 ** 2022 ATLANTIC RI INDEX AL072021 GRACE 08/14/21 18 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 8.7 850-200 MB SHEAR (KT) : 5.9 28.5 to 2.0 0.85 4.9 HEAT CONTENT (KJ/CM2) : 39.4 0.0 to 161.7 0.24 1.4 STD DEV OF IR BR TEMP : 6.2 36.6 to 2.8 0.90 4.4 MAXIMUM WIND (KT) : 40.0 22.5 to 137.5 0.46 1.9 BL DRY-AIR FLUX (W/M2) : 212.8 895.4 to -71.5 0.71 2.6 POT = MPI-VMAX (KT) : 102.3 27.0 to 140.8 0.66 1.2 2nd PC OF IR BR TEMP : 0.4 2.9 to -3.0 0.42 1.2 D200 (10**7s-1) : 48.8 -30.8 to 188.1 0.36 0.9 %area of TPW <45 mm upshear : 6.0 104.5 to 0.0 0.94 0.2 SHIPS Prob RI for 20kt/ 12hr RI threshold= 10% is 2.1 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 39% is 3.6 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 27% is 4.0 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 19% is 4.8 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 12% is 5.0 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 25% is 5.5 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= 31% is 5.8 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: 10.2% 39.5% 27.4% 18.6% 11.9% 25.2% 25.0% 30.6% Logistic: 27.9% 54.4% 44.6% 39.0% 22.6% 37.8% 35.7% 30.2% Bayesian: 14.7% 55.9% 45.6% 11.7% 11.0% 27.4% 16.7% 15.1% Consensus: 17.6% 49.9% 39.2% 23.1% 15.2% 30.1% 25.8% 25.3% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/14/21 18 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 AL072021 GRACE 08/14/2021 18 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) 9( 9) <-- 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 55 61 70 72 50 43 44 45 49 53 55 61 63 66 18HR AGO 40 39 44 49 55 64 66 44 37 38 39 43 47 49 55 57 60 12HR AGO 40 37 36 41 47 56 58 36 29 30 31 35 39 41 47 49 52 6HR AGO 40 34 31 30 36 45 47 25 18 19 DIS DIS DIS DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT