* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/19/21 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 70 74 76 77 79 79 79 72 67 66 66 68 70 73 74 76 77 V (KT) LAND 70 74 60 46 49 50 49 35 29 27 31 33 35 38 39 41 42 V (KT) LGEM 70 75 64 48 49 55 58 39 31 28 31 N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP N/A N/A N/A N/A N/A N/A SHEAR (KT) 13 15 15 13 6 17 18 17 4 3 4 N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) -3 0 3 -1 0 2 -1 0 5 10 11 N/A N/A N/A N/A N/A N/A SHEAR DIR 297 331 344 13 5 350 342 11 40 301 45 N/A N/A N/A N/A N/A N/A SST (C) 30.1 29.7 29.3 29.7 30.2 30.1 30.3 29.2 28.4 28.8 29.9 N/A N/A N/A N/A N/A N/A POT. INT. (KT) 173 166 159 166 173 172 172 156 143 148 168 N/A N/A N/A N/A N/A N/A ADJ. POT. INT. 172 162 154 161 169 164 169 148 133 138 158 N/A N/A N/A N/A N/A N/A 200 MB T (C) -52.2 -52.6 -52.6 -52.4 -52.1 -52.4 -51.8 -51.9 -51.7 -51.8 -51.3 N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 0.6 0.7 0.7 0.7 0.6 0.5 0.8 0.7 0.4 0.2 0.0 N/A N/A N/A N/A N/A N/A TH_E DEV (C) 11 9 9 10 10 8 11 8 11 7 9 N/A N/A N/A N/A N/A N/A 700-500 MB RH 58 56 56 58 58 60 64 69 74 80 81 N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 19 20 21 19 20 20 18 11 5 3 LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR -4 -15 -25 -22 -16 3 48 78 91 96 106 N/A N/A N/A N/A N/A N/A 200 MB DIV 59 43 17 19 20 13 13 23 63 55 58 N/A N/A N/A N/A N/A N/A 700-850 TADV -3 -7 -10 -7 -7 -9 -7 -6 -6 4 -1 N/A N/A N/A N/A N/A N/A LAND (KM) 222 99 -62 -70 74 265 78 -204 -217 -107 26 N/A N/A N/A N/A N/A N/A LAT (DEG N) 19.8 20.1 20.4 20.6 20.7 20.8 20.6 20.1 19.8 19.5 19.3 N/A N/A N/A N/A N/A N/A LONG(DEG W) 84.8 86.3 87.9 89.5 91.1 93.6 96.1 98.9 101.2 103.2 105.2 N/A N/A N/A N/A N/A N/A STM SPEED (KT) 15 15 15 15 14 12 12 12 10 10 9 N/A N/A N/A N/A N/A N/A HEAT CONTENT 85 47 27 23 40 33 40 5 11 14 25 N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 16 CX,CY: -15/ 3 T-12 MAX WIND: 60 PRESSURE OF STEERING LEVEL (MB): 625 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 21.0 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 74.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 9.5 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 2. 3. 5. 6. 6. 7. 7. 8. 8. 9. 11. 12. 12. 12. 11. 11. VERTICAL SHEAR MAG -1. -2. -2. -2. -2. -2. -1. 1. 4. 6. 7. 8. 9. 10. 10. 10. VERTICAL SHEAR ADJ 0. 0. 0. 1. 1. 1. 1. 1. -0. -1. -1. -1. -1. -1. -1. -1. VERTICAL SHEAR DIR -0. -0. 0. 0. 1. 1. 1. 2. 2. 3. 3. 3. 4. 4. 4. 4. PERSISTENCE 2. 2. 2. 2. 1. 1. 1. 1. 0. -0. -0. -0. 0. 0. 1. 1. 200/250 MB TEMP. -0. -0. -1. -1. -2. -2. -2. -3. -3. -3. -4. -4. -5. -5. -4. -5. THETA_E EXCESS 0. 0. 0. 0. 1. 1. 1. 1. 0. 0. 0. 0. -0. -0. -0. -0. 700-500 MB RH -0. -0. -0. -0. -0. -1. -2. -3. -4. -5. -6. -6. -6. -7. -8. -7. MODEL VTX TENDENCY 0. 1. -1. -0. -1. -3. -13. -23. -26. -30. -31. -31. -30. -29. -28. -27. 850 MB ENV VORTICITY -0. -0. -0. -1. -1. -1. -1. -0. 0. 1. 1. 1. 1. 1. 1. 1. 200 MB DIVERGENCE 0. 0. 0. -0. -0. -0. -1. -0. -0. 0. 0. -0. -0. -0. -0. -0. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -1. -1. -1. -0. -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. -0. -0. -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 0. -0. -1. -0. 0. 1. 2. 2. 3. 3. 3. 3. 2. 1. 1. 0. OCEAN HEAT CONTENT -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 0. 0. 0. -0. -0. -0. -0. -0. -0. 0. 0. 1. 1. 1. 1. 1. ------------------------------------------------------------------------------ TOTAL CHANGE 4. 6. 7. 9. 9. 9. 2. -3. -4. -4. -2. 0. 3. 4. 6. 7. CURRENT MAX WIND (KT): 70. LAT, LON: 19.8 84.8 ** 2022 ATLANTIC RI INDEX AL072021 GRACE 08/19/21 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) : 10.0 -49.5 to 33.0 0.72 4.5 850-200 MB SHEAR (KT) : 12.4 28.5 to 2.0 0.61 1.7 HEAT CONTENT (KJ/CM2) : 44.4 0.0 to 161.7 0.27 0.8 STD DEV OF IR BR TEMP : 21.0 36.6 to 2.8 0.46 1.1 MAXIMUM WIND (KT) : 70.0 22.5 to 137.5 0.88 1.7 BL DRY-AIR FLUX (W/M2) : 384.8 895.4 to -71.5 0.53 0.9 POT = MPI-VMAX (KT) : 93.7 27.0 to 140.8 0.59 0.5 2nd PC OF IR BR TEMP : 1.1 2.9 to -3.0 0.30 0.4 D200 (10**7s-1) : 31.6 -30.8 to 188.1 0.29 0.3 %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= 11% is 2.3 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 20% is 1.8 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 12% is 1.8 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 9% is 2.2 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= 10% is 2.2 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.5 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 12% is 2.3 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: 11.0% 20.1% 12.0% 8.7% 8.1% 10.1% 11.7% 12.2% Logistic: 7.1% 18.9% 13.7% 11.9% 5.9% 10.8% 8.7% 13.4% Bayesian: 6.0% 7.3% 3.5% 0.3% 0.2% 1.7% 1.7% 8.3% Consensus: 8.0% 15.4% 9.7% 7.0% 4.7% 7.5% 7.4% 11.3% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/19/21 00 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=3 NFAIL=4 ## ## 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 08/19/2021 00 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 4 0( 4) 0( 4) 0( 4) <-- 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) 70 74 60 46 49 50 49 35 29 27 31 33 35 38 39 41 42 18HR AGO 70 69 55 41 44 45 44 30 24 22 26 28 30 33 34 36 37 12HR AGO 70 67 66 52 55 56 55 41 35 33 37 39 41 44 45 47 48 6HR AGO 70 64 61 60 63 64 63 49 43 41 45 47 49 52 53 55 56 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT