* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/16/21 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 33 35 38 43 50 58 66 70 74 76 80 77 73 74 77 78 V (KT) LAND 30 33 34 37 41 49 56 65 63 67 69 73 53 35 29 28 27 V (KT) LGEM 30 31 28 33 35 40 45 51 50 59 67 76 56 36 29 N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP N/A N/A SHEAR (KT) 7 9 13 12 11 14 3 14 11 8 7 15 15 15 5 N/A N/A SHEAR ADJ (KT) -1 3 2 4 1 0 0 0 0 3 3 0 2 7 15 N/A N/A SHEAR DIR 296 253 274 286 282 276 298 302 18 341 32 342 357 351 19 N/A N/A SST (C) 29.1 29.6 29.7 29.8 30.2 29.6 29.8 29.4 29.6 30.2 30.4 30.2 29.4 29.4 28.3 N/A N/A POT. INT. (KT) 154 163 165 167 173 164 168 160 164 172 171 171 158 158 141 N/A N/A ADJ. POT. INT. 149 161 162 164 172 161 164 155 157 165 163 158 144 144 129 N/A N/A 200 MB T (C) -53.7 -53.5 -53.6 -53.7 -53.5 -53.3 -53.0 -52.7 -52.4 -52.2 -52.1 -51.6 -51.5 -51.6 -51.8 N/A N/A 200 MB VXT (C) -0.1 0.0 0.0 -0.1 0.1 0.5 0.5 0.8 0.6 0.8 0.8 0.6 1.0 0.0 0.0 N/A N/A TH_E DEV (C) 11 11 11 11 11 10 11 10 11 10 11 10 12 10 11 N/A N/A 700-500 MB RH 58 56 53 55 57 56 56 53 54 53 57 62 65 71 73 N/A N/A MODEL VTX (KT) 9 9 8 8 10 12 13 16 17 17 17 18 13 LOST LOST LOST LOST 850 MB ENV VOR 13 17 3 0 9 -6 -18 -23 -15 -2 10 39 44 79 69 N/A N/A 200 MB DIV 42 57 13 7 21 16 34 28 21 13 13 9 26 39 44 N/A N/A 700-850 TADV -5 -12 -16 -20 -12 -26 -12 -19 -11 -15 -5 -11 -8 -13 14 N/A N/A LAND (KM) 20 11 15 70 65 236 172 42 71 272 262 102 -92 -292 -286 N/A N/A LAT (DEG N) 17.8 18.1 18.4 18.7 19.0 19.6 20.4 21.2 21.8 22.2 22.6 22.8 23.0 xx.x xx.x N/A N/A LONG(DEG W) 71.8 73.2 74.6 76.0 77.4 80.3 83.5 86.5 89.8 92.6 94.9 96.8 98.7 xxx.x xxx.x N/A N/A STM SPEED (KT) 12 14 14 14 14 15 15 15 15 12 9 9 9 10 10 N/A N/A HEAT CONTENT 33 40 44 50 66 84 89 33 29 54 48 32 24 24 12 N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):285/ 11 CX,CY: -10/ 3 T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 584 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 9.9 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 97.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 29.5 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 0. -1. -1. -1. 1. 7. 14. 19. 24. 28. 33. 38. 43. 44. 46. 45. VERTICAL SHEAR MAG 1. 2. 3. 4. 5. 7. 7. 7. 7. 7. 7. 6. 5. 5. 5. 6. VERTICAL SHEAR ADJ -0. -0. -0. -0. -0. -0. 0. -0. 0. -0. -0. -0. -0. -1. -1. -1. VERTICAL SHEAR DIR -0. -0. -1. -1. -2. -2. -2. -2. -2. -1. -1. -1. -1. -1. -1. -1. PERSISTENCE -0. -1. -1. -1. -0. -0. -0. -0. -0. 0. 0. 0. -0. -0. -1. -0. 200/250 MB TEMP. -0. -1. -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. -1. -1. -1. -1. -1. -2. -3. -3. -4. -3. MODEL VTX TENDENCY 0. -1. -1. 0. 1. 3. 6. 7. 7. 6. 6. -2. -9. -9. -9. -9. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -1. -2. -2. -2. -2. -2. -1. -1. -1. -1. 200 MB DIVERGENCE 0. 0. -0. -0. -0. -0. -0. -0. -1. -0. -0. 0. 0. 0. 0. 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. 1. 1. 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. 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. 2. 4. 5. 8. 7. 5. 3. 0. -1. -3. -4. -5. -5. -5. -5. ------------------------------------------------------------------------------ TOTAL CHANGE 3. 5. 8. 13. 20. 28. 36. 40. 44. 46. 50. 47. 43. 44. 47. 48. CURRENT MAX WIND (KT): 30. LAT, LON: 17.8 71.8 ** 2021 ATLANTIC RI INDEX AL072021 GRACE 08/16/21 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) : 0.0 -49.5 to 33.0 0.60 2.9 850-200 MB SHEAR (KT) : 10.5 30.1 to 2.3 0.71 1.6 HEAT CONTENT (KJ/CM2) : 46.6 0.0 to 151.8 0.31 0.6 STD DEV OF IR BR TEMP : 9.9 36.6 to 2.8 0.79 1.8 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.4 BL DRY-AIR FLUX (W/M2) : 190.2 895.4 to -55.0 0.74 1.4 2nd PC OF IR BR TEMP : 0.6 2.9 to -2.9 0.40 0.5 POT = MPI-VMAX (KT) : 131.5 28.3 to 146.3 0.87 0.8 D200 (10**7s-1) : 28.0 -29.7 to 185.9 0.27 0.2 %area of TPW <45 mm upshear : 0.0 100.0 to 0.0 1.00 0.2 SHIPS Prob RI for 20kt/ 12hr RI threshold= 5% is 1.1 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 17% is 1.6 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 11% is 1.5 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 9% is 2.3 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 7% is 2.8 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 11% is 2.4 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.6 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 19% is 3.6 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: 5.4% 17.3% 10.5% 8.9% 6.8% 10.8% 12.0% 19.0% Logistic: 15.0% 34.8% 25.2% 26.6% 16.3% 37.7% 45.5% 47.5% Bayesian: 4.4% 27.2% 12.6% 1.5% 0.7% 2.3% 1.5% 2.0% Consensus: 8.3% 26.4% 16.1% 12.3% 7.9% 17.0% 19.7% 22.9% DTOPS: 0.0% 2.0% 1.0% 0.0% 0.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/16/21 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 08/16/2021 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 33 34 37 41 49 56 65 63 67 69 73 53 35 29 28 27 18HR AGO 30 29 30 33 37 45 52 61 59 63 65 69 49 31 25 24 23 12HR AGO 30 27 26 29 33 41 48 57 55 59 61 65 45 27 21 20 19 6HR AGO 30 24 21 20 24 32 39 48 46 50 52 56 36 18 DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT