* ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/17/21 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 30 32 35 37 42 48 58 62 68 69 71 70 65 69 72 74 75 V (KT) LAND 30 28 33 36 41 47 56 47 54 54 57 49 35 29 28 27 27 V (KT) LGEM 30 27 32 33 35 40 45 41 46 52 58 60 36 N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP N/A N/A N/A N/A SHEAR (KT) 9 12 13 11 9 12 9 15 7 13 9 18 17 N/A N/A N/A N/A SHEAR ADJ (KT) 2 2 2 0 -2 0 0 0 -2 5 1 4 0 N/A N/A N/A N/A SHEAR DIR 281 286 297 294 256 314 291 339 336 5 340 349 344 N/A N/A N/A N/A SST (C) 29.5 29.6 29.7 30.1 30.0 29.9 30.0 28.8 29.9 30.2 30.2 30.1 29.9 N/A N/A N/A N/A POT. INT. (KT) 161 163 165 173 172 170 172 150 169 172 171 170 167 N/A N/A N/A N/A ADJ. POT. INT. 156 159 162 172 170 167 168 145 161 163 160 154 151 N/A N/A N/A N/A 200 MB T (C) -53.4 -53.5 -53.7 -53.5 -53.1 -53.3 -52.8 -52.9 -52.1 -52.4 -52.0 -52.2 -52.0 N/A N/A N/A N/A 200 MB VXT (C) 0.1 0.1 0.1 0.1 0.4 0.4 0.4 0.6 0.7 0.8 0.5 0.7 1.0 N/A N/A N/A N/A TH_E DEV (C) 12 12 11 11 11 10 11 10 11 8 12 9 12 N/A N/A N/A N/A 700-500 MB RH 55 52 53 57 58 54 57 54 55 57 61 65 71 N/A N/A N/A N/A MODEL VTX (KT) 9 7 7 8 11 11 14 13 15 15 15 12 6 LOST LOST LOST LOST 850 MB ENV VOR 12 -3 0 8 3 -27 -18 -42 -1 -6 14 33 58 N/A N/A N/A N/A 200 MB DIV 57 18 7 11 22 20 43 16 9 -7 8 9 14 N/A N/A N/A N/A 700-850 TADV -8 -10 -16 -12 -15 -19 -10 -21 -10 -10 -9 -12 -10 N/A N/A N/A N/A LAND (KM) 16 -4 91 54 112 252 145 -37 129 357 152 -2 -158 N/A N/A N/A N/A LAT (DEG N) 18.0 18.3 18.5 18.9 19.2 19.8 20.5 21.2 21.8 22.2 22.4 22.4 22.2 N/A N/A N/A N/A LONG(DEG W) 73.0 74.3 75.6 77.1 78.7 81.8 84.9 88.2 91.2 93.8 96.0 97.9 99.4 N/A N/A N/A N/A STM SPEED (KT) 12 13 14 15 15 15 15 15 13 11 10 7 7 N/A N/A N/A N/A HEAT CONTENT 39 43 48 61 83 96 87 24 31 50 37 30 29 N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 11 CX,CY: -10/ 2 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 585 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 7.2 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 100.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 25.2 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. -1. -1. -1. 1. 7. 14. 19. 24. 28. 33. 38. 43. 45. 47. 47. VERTICAL SHEAR MAG 1. 2. 3. 4. 5. 6. 6. 6. 5. 5. 3. 2. 1. 1. 1. 2. VERTICAL SHEAR ADJ -0. -0. -0. -0. 0. 1. 1. 1. 1. 1. 1. 1. 0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. -0. -0. -0. PERSISTENCE -0. -1. -1. -1. -0. -0. -0. -0. -0. 0. 0. 0. -0. -0. -1. -0. 200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -1. -1. -2. -2. -2. -3. -3. -3. -3. -3. THETA_E EXCESS 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 0. 0. -0. -0. -1. -1. 700-500 MB RH 0. 0. 0. -0. -0. -0. -0. -1. -1. -1. -2. -2. -3. -3. -3. -3. MODEL VTX TENDENCY -1. -1. -1. 1. 0. 3. 2. 4. 3. 3. -2. -11. -12. -12. -12. -12. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -2. -2. -2. -2. -2. -2. -2. -2. -2. -2. 200 MB DIVERGENCE 0. -0. -0. -0. -0. -0. -0. -1. -1. -1. -0. 0. 0. 0. 1. 1. 850-700 T ADVEC 0. -0. -0. -0. -1. -2. -2. -2. -1. -1. -0. -0. -0. -0. -0. -0. ZONAL STORM MOTION -0. -0. 0. 0. 0. 1. 1. 1. 1. 1. 2. 2. 1. 1. 1. 1. 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. 1. 0. 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. 2. 3. 4. 6. 6. 4. 2. 0. -1. -2. -3. -4. -4. -4. -4. ------------------------------------------------------------------------------ TOTAL CHANGE 2. 5. 7. 12. 18. 28. 32. 38. 39. 41. 40. 35. 39. 42. 44. 45. CURRENT MAX WIND (KT): 30. LAT, LON: 18.0 73.0 ** 2022 ATLANTIC RI INDEX AL072021 GRACE 08/17/21 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) : 0.0 -49.5 to 33.0 0.60 4.2 MULTI-LAYER SHEAR (KT) : 20.5 45.1 to 6.7 0.64 2.4 HEAT CONTENT (KJ/CM2) : 54.8 0.0 to 161.7 0.34 1.0 STD DEV OF IR BR TEMP : 7.2 36.6 to 2.8 0.87 2.5 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.4 POT = MPI-VMAX (KT) : 133.6 27.0 to 140.8 0.94 1.3 D200 (10**7s-1) : 23.0 -30.8 to 188.1 0.25 0.4 2nd PC OF IR BR TEMP : 0.2 2.9 to -3.0 0.46 0.7 BL DRY-AIR FLUX (W/M2) : 198.6 895.4 to -71.5 0.72 1.0 %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= 26% is 2.4 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 14% is 2.1 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 9% is 2.4 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 9% is 3.9 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 15% is 3.2 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 21% is 4.4 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 32% is 6.1 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: 6.7% 26.3% 14.1% 9.4% 9.4% 14.8% 20.7% 32.2% Logistic: 26.6% 51.0% 41.9% 46.2% 33.9% 48.2% 58.9% 59.4% Bayesian: 4.4% 28.0% 14.2% 1.3% 1.6% 1.5% 0.6% 1.7% Consensus: 12.5% 35.1% 23.4% 19.0% 15.0% 21.5% 26.7% 31.1% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/17/21 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 08/17/2021 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 28 33 36 41 47 56 47 54 54 57 49 35 29 28 27 27 18HR AGO 30 29 34 37 42 48 57 48 55 55 58 50 36 30 29 28 28 12HR AGO 30 27 26 29 34 40 49 40 47 47 50 42 28 22 21 20 20 6HR AGO 30 24 21 20 25 31 40 31 38 38 41 33 19 DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT