* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/16/21 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 31 33 35 38 39 45 48 54 55 62 65 69 74 76 76 75 V (KT) LAND 30 31 33 31 30 35 36 39 39 44 51 54 58 63 65 65 64 V (KT) LGEM 30 29 29 27 27 31 31 33 31 37 41 45 48 52 57 60 62 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 10 15 15 10 11 16 13 15 3 16 10 16 11 18 12 15 7 SHEAR ADJ (KT) 0 -1 -3 1 5 3 -1 0 5 3 2 6 -3 3 -3 3 -2 SHEAR DIR 302 305 318 291 262 287 285 331 346 2 360 1 329 345 314 351 317 SST (C) 29.0 28.9 28.6 29.0 29.6 29.3 30.2 29.9 30.3 29.6 29.9 30.3 30.6 30.6 30.5 30.5 30.3 POT. INT. (KT) 153 150 146 152 163 158 173 170 173 163 168 171 171 170 169 168 167 ADJ. POT. INT. 149 144 139 146 157 152 171 165 170 150 152 158 163 160 155 150 144 200 MB T (C) -53.7 -53.9 -54.0 -53.6 -53.3 -53.7 -53.5 -53.7 -53.2 -53.3 -52.8 -52.9 -52.4 -52.5 -52.3 -52.4 -52.1 200 MB VXT (C) 0.3 0.2 0.1 0.1 0.2 0.2 0.3 0.4 0.2 0.4 0.4 0.5 0.2 0.4 0.3 0.4 0.2 TH_E DEV (C) 11 11 11 11 11 10 10 9 9 8 8 8 10 9 11 9 12 700-500 MB RH 59 58 56 56 56 55 61 58 60 58 59 57 54 56 62 64 71 MODEL VTX (KT) 10 10 10 10 11 8 10 9 10 8 12 10 9 10 9 8 6 850 MB ENV VOR 6 3 6 13 18 -12 -16 -44 -35 -47 -43 -41 -9 -8 15 1 -3 200 MB DIV 42 38 44 43 38 18 7 0 34 19 14 25 9 -7 8 -1 36 700-850 TADV -12 -10 -8 -9 -14 -19 -17 -24 -23 -32 -20 -21 -15 -12 -12 -21 -4 LAND (KM) 128 99 71 -26 -4 39 33 69 -18 220 281 387 484 327 211 135 105 LAT (DEG N) 17.1 17.4 17.6 18.0 18.4 19.5 20.4 21.3 22.5 23.4 24.1 24.6 24.9 xx.x xx.x xx.x xx.x LONG(DEG W) 68.1 69.2 70.3 71.4 72.5 74.8 77.7 80.6 83.8 86.4 88.4 90.4 92.4 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 13 11 11 11 12 13 14 15 14 11 10 9 9 7 5 2 1 HEAT CONTENT 62 46 28 27 37 43 71 70 94 57 40 50 66 69 50 40 35 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):275/ 14 CX,CY: -13/ 1 T-12 MAX WIND: 35 PRESSURE OF STEERING LEVEL (MB): 622 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 15.2 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 93.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 8.7 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. 0. 1. 3. 8. 14. 19. 24. 28. 33. 38. 42. 44. 46. 45. VERTICAL SHEAR MAG 1. 2. 3. 3. 5. 5. 4. 4. 3. 2. 1. 1. -0. -1. -1. 0. VERTICAL SHEAR ADJ 0. 0. 0. 0. 0. 0. 1. 0. 0. 0. -0. -0. -0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. -0. -1. -1. -2. -2. -1. -1. -1. -1. -1. -1. -1. -1. -0. PERSISTENCE -1. -2. -2. -2. -1. -1. -1. -1. -0. -0. 0. 0. -0. -1. -2. -2. 200/250 MB TEMP. -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -0. -0. THETA_E EXCESS 0. 0. 1. 1. 1. 1. 1. 1. 1. 0. 0. 0. -0. -0. -0. -0. 700-500 MB RH -0. -0. -0. -0. -0. -1. -1. -1. -2. -2. -2. -2. -2. -3. -3. -3. MODEL VTX TENDENCY -0. -1. -0. -0. -3. -2. -5. -4. -8. -4. -7. -9. -9. -9. -11. -13. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -1. -2. -2. -3. -3. -3. -3. -3. -4. -4. 200 MB DIVERGENCE 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -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. 1. 1. 1. 1. 2. 2. 3. 3. 3. 3. 3. 3. 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. 1. 2. 2. 1. 1. 1. 1. 1. 0. 0. 1. 2. 2. 2. 2. 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. -1. -1. -1. -0. -0. 0. 0. 1. 1. 1. 1. 1. ------------------------------------------------------------------------------ TOTAL CHANGE 1. 3. 5. 8. 9. 15. 18. 24. 25. 32. 35. 39. 44. 46. 46. 45. CURRENT MAX WIND (KT): 30. LAT, LON: 17.1 68.1 ** 2021 ATLANTIC RI INDEX AL072021 GRACE 08/16/21 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) : -5.0 -49.5 to 33.0 0.54 2.3 850-200 MB SHEAR (KT) : 12.1 30.1 to 2.3 0.65 1.3 HEAT CONTENT (KJ/CM2) : 40.0 0.0 to 151.8 0.26 0.5 STD DEV OF IR BR TEMP : 15.2 36.6 to 2.8 0.63 1.3 MAXIMUM WIND (KT) : 30.0 22.5 to 137.5 0.20 0.3 BL DRY-AIR FLUX (W/M2) : 190.0 895.4 to -55.0 0.74 1.2 2nd PC OF IR BR TEMP : 0.2 2.9 to -2.9 0.46 0.5 POT = MPI-VMAX (KT) : 117.0 28.3 to 146.3 0.75 0.6 D200 (10**7s-1) : 41.0 -29.7 to 185.9 0.33 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= 4% is 0.8 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 13% is 1.2 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 8% is 1.2 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 7% is 1.8 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 5% is 2.3 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 9% is 1.9 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 10% is 2.0 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 16% 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: 3.8% 13.1% 8.5% 7.2% 5.4% 8.9% 9.6% 15.5% Logistic: 9.3% 25.8% 15.6% 12.9% 8.1% 17.9% 33.8% 38.9% Bayesian: 1.8% 10.8% 3.7% 0.2% 0.2% 1.0% 2.3% 1.1% Consensus: 5.0% 16.6% 9.2% 6.8% 4.6% 9.3% 15.2% 18.5% DTOPS: 999.0% 999.0% 999.0% 999.0% 999.0% 999.0% 999.0% 999.0% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/16/21 00 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 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 31 33 31 30 35 36 39 39 44 51 54 58 63 65 65 64 18HR AGO 30 29 31 29 28 33 34 37 37 42 49 52 56 61 63 63 62 12HR AGO 30 27 26 24 23 28 29 32 32 37 44 47 51 56 58 58 57 6HR AGO 30 24 21 20 19 24 25 28 28 33 40 43 47 52 54 54 53 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT