* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/15/21 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 30 31 32 34 35 37 37 39 40 43 46 51 57 61 63 66 67 V (KT) LAND 30 31 32 34 30 31 28 27 27 29 32 37 43 47 49 52 53 V (KT) LGEM 30 29 29 29 27 27 26 26 27 30 31 34 37 41 44 48 51 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 11 11 15 16 13 18 18 22 13 18 7 15 13 20 8 22 13 SHEAR ADJ (KT) 1 3 3 -1 3 6 3 0 2 0 4 3 0 1 -3 -1 -5 SHEAR DIR 289 274 296 311 281 274 285 291 321 310 343 301 289 309 278 297 284 SST (C) 28.9 28.9 28.8 28.6 28.7 29.4 29.0 29.9 30.0 30.1 30.0 30.0 30.2 30.2 30.2 30.3 30.3 POT. INT. (KT) 151 150 148 145 147 159 153 169 171 173 171 169 170 169 169 170 170 ADJ. POT. INT. 149 144 141 137 140 152 145 163 163 162 157 151 151 147 145 149 151 200 MB T (C) -53.9 -53.9 -54.1 -54.1 -53.8 -53.8 -53.8 -53.8 -53.5 -53.5 -53.2 -52.9 -52.5 -52.4 -52.2 -51.9 -51.8 200 MB VXT (C) 0.2 0.3 0.2 0.1 0.2 0.1 -0.2 0.4 0.2 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 TH_E DEV (C) 10 11 11 11 10 10 9 8 9 9 9 9 9 9 9 9 9 700-500 MB RH 62 61 61 59 60 59 62 62 64 61 63 57 60 55 58 56 60 MODEL VTX (KT) 9 10 8 8 7 7 6 6 5 4 LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 14 11 0 0 2 -4 -11 -41 -37 -48 -45 -58 -34 -55 -20 -45 -33 200 MB DIV 62 56 51 42 41 42 28 19 39 23 13 0 3 -1 18 18 26 700-850 TADV -14 -14 -13 -12 -7 -27 -24 -40 -20 -29 -17 -37 -16 -40 -7 -38 -6 LAND (KM) 101 93 46 27 -13 5 -32 -59 -44 85 317 386 300 250 245 242 140 LAT (DEG N) 17.0 17.4 17.7 18.1 18.5 19.4 20.4 21.4 22.4 23.6 24.8 25.7 26.4 xx.x xx.x xx.x xx.x LONG(DEG W) 66.7 67.8 68.8 69.7 70.7 72.9 75.3 78.0 80.8 83.4 86.0 88.1 89.8 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 14 11 10 10 11 12 13 14 14 13 12 9 7 5 5 6 7 HEAT CONTENT 69 56 41 27 23 35 41 55 70 64 88 72 79 36 31 32 31 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):275/ 16 CX,CY: -15/ 1 T-12 MAX WIND: 35 PRESSURE OF STEERING LEVEL (MB): 635 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 11.0 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 95.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 5.8 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. 1. 1. 4. 8. 14. 19. 24. 28. 32. 36. 40. 41. 43. 42. VERTICAL SHEAR MAG 1. 2. 2. 3. 4. 4. 2. 0. -1. -2. -2. -3. -4. -4. -5. -4. VERTICAL SHEAR ADJ -0. -0. -0. -0. -1. -2. -2. -2. -1. -1. -1. -1. -1. -0. -0. 0. VERTICAL SHEAR DIR -0. -0. -0. -1. -1. -2. -2. -2. -2. -2. -2. -2. -2. -2. -2. -2. PERSISTENCE -1. -2. -2. -2. -1. -1. -1. -1. -0. -0. 0. 0. -0. -1. -2. -2. 200/250 MB TEMP. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. 0. 1. 2. THETA_E EXCESS 0. 0. 0. 1. 1. 1. 1. 1. 0. 0. 0. 0. -0. -0. -0. -0. 700-500 MB RH -0. -0. -0. -0. -1. -1. -2. -2. -3. -3. -3. -4. -4. -4. -4. -4. MODEL VTX TENDENCY 0. -0. -1. -2. -3. -5. -7. -10. -11. -13. -14. -14. -15. -15. -14. -14. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -1. -2. -2. -3. -3. -4. -4. -4. -5. -5. 200 MB DIVERGENCE 0. 0. 0. 0. 1. 0. 0. 0. 0. 0. -0. 0. 0. 0. 0. 1. 850-700 T ADVEC 0. -0. -0. -0. -1. -2. -3. -3. -2. -1. -0. -0. -0. -0. -0. -0. ZONAL STORM MOTION -0. -0. 0. 0. 1. 1. 1. 1. 2. 3. 3. 3. 3. 3. 4. 4. STEERING LEVEL PRES -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -1. -1. -0. -0. -0. -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. 1. 1. 1. 1. 0. 0. -0. 1. 2. 2. 3. 2. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL -0. -0. -1. -1. -2. -2. -1. -1. -0. 0. 1. 1. 2. 2. 2. 2. ------------------------------------------------------------------------------ TOTAL CHANGE 1. 2. 4. 5. 7. 7. 9. 10. 13. 16. 21. 27. 31. 33. 36. 37. CURRENT MAX WIND (KT): 30. LAT, LON: 17.0 66.7 ** 2022 ATLANTIC RI INDEX AL072021 GRACE 08/15/21 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 0.54 3.1 MULTI-LAYER SHEAR (KT) : 23.4 45.1 to 6.7 0.57 1.8 HEAT CONTENT (KJ/CM2) : 43.2 0.0 to 161.7 0.27 0.6 STD DEV OF IR BR TEMP : 11.0 36.6 to 2.8 0.76 1.8 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.4 POT = MPI-VMAX (KT) : 112.1 27.0 to 140.8 0.75 0.9 D200 (10**7s-1) : 50.4 -30.8 to 188.1 0.37 0.5 2nd PC OF IR BR TEMP : 0.3 2.9 to -3.0 0.43 0.5 BL DRY-AIR FLUX (W/M2) : 165.0 895.4 to -71.5 0.76 0.9 %area of TPW <45 mm upshear : 5.8 104.5 to 0.0 0.94 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 6% is 1.2 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 16% is 1.5 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 1.9 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= 10% is 2.1 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 10% is 2.1 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 15% is 2.9 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: 5.7% 15.9% 10.5% 7.6% 7.5% 9.8% 9.7% 15.5% Logistic: 8.2% 16.6% 9.3% 7.8% 4.0% 11.8% 15.7% 14.8% Bayesian: 2.0% 13.0% 5.9% 0.4% 0.4% 1.6% 0.4% 0.8% Consensus: 5.3% 15.1% 8.6% 5.3% 3.9% 7.7% 8.6% 10.4% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/15/21 18 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=5 NFAIL=2 ## ## 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 08/15/2021 18 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 0 0( 0) 0( 0) 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 31 32 34 30 31 28 27 27 29 32 37 43 47 49 52 53 18HR AGO 30 29 30 32 28 29 26 25 25 27 30 35 41 45 47 50 51 12HR AGO 30 27 26 28 24 25 22 21 21 23 26 31 37 41 43 46 47 6HR AGO 30 24 21 20 16 17 DIS DIS DIS DIS 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