* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/19/21 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 50 47 47 48 51 52 50 47 50 55 58 63 67 70 69 70 71 V (KT) LAND 50 50 50 50 53 46 33 29 27 27 27 27 27 27 27 27 27 V (KT) LGEM 50 48 46 46 47 41 31 28 N/A N/A N/A N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP N/A N/A N/A N/A N/A N/A N/A N/A N/A SHEAR (KT) 11 6 8 12 11 14 12 12 N/A N/A N/A N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) 0 1 1 2 0 -1 0 0 N/A N/A N/A N/A N/A N/A N/A N/A N/A SHEAR DIR 356 353 347 359 354 337 57 73 N/A N/A N/A N/A N/A N/A N/A N/A N/A SST (C) 29.7 30.0 30.0 30.1 30.2 28.9 28.7 28.8 N/A N/A N/A N/A N/A N/A N/A N/A N/A POT. INT. (KT) 166 171 171 172 172 151 149 150 N/A N/A N/A N/A N/A N/A N/A N/A N/A ADJ. POT. INT. 161 166 164 164 164 142 143 145 N/A N/A N/A N/A N/A N/A N/A N/A N/A 200 MB T (C) -52.3 -52.0 -52.2 -52.4 -52.0 -51.7 -51.5 -51.7 N/A N/A N/A N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 0.7 0.7 0.7 0.6 0.5 0.9 1.0 0.4 N/A N/A N/A N/A N/A N/A N/A N/A N/A TH_E DEV (C) 11 11 9 8 11 10 11 8 N/A N/A N/A N/A N/A N/A N/A N/A N/A 700-500 MB RH 55 56 57 57 62 62 70 73 N/A N/A N/A N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 22 20 20 20 21 17 10 5 LOST LOST LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR -7 -9 -15 -3 19 54 80 93 N/A N/A N/A N/A N/A N/A N/A N/A N/A 200 MB DIV 23 12 10 -5 25 14 46 19 N/A N/A N/A N/A N/A N/A N/A N/A N/A 700-850 TADV -2 -1 -13 -5 0 -8 -3 -5 N/A N/A N/A N/A N/A N/A N/A N/A N/A LAND (KM) -76 62 217 253 177 -48 -286 -115 N/A N/A N/A N/A N/A N/A N/A N/A N/A LAT (DEG N) 20.5 20.6 20.7 20.7 20.6 20.3 19.8 19.5 N/A N/A N/A N/A N/A N/A N/A N/A N/A LONG(DEG W) 89.5 91.0 92.5 93.8 95.0 97.3 100.0 103.1 N/A N/A N/A N/A N/A N/A N/A N/A N/A STM SPEED (KT) 15 14 13 12 11 12 14 14 N/A N/A N/A N/A N/A N/A N/A N/A N/A HEAT CONTENT 17 44 29 33 40 16 9 14 N/A N/A N/A N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 15 CX,CY: -14/ 3 T-12 MAX WIND: 70 PRESSURE OF STEERING LEVEL (MB): 609 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 18.8 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 73.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 5.0 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 1. 2. 2. 3. 5. 8. 11. 15. 18. 20. 23. 26. 28. 28. 29. 28. VERTICAL SHEAR MAG 0. 1. 2. 2. 3. 3. 4. 5. 5. 5. 5. 6. 6. 6. 7. 7. VERTICAL SHEAR ADJ 0. 0. -0. 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. VERTICAL SHEAR DIR 0. 0. 0. 0. 1. 2. 3. 3. 3. 4. 4. 5. 5. 5. 5. 5. PERSISTENCE -4. -6. -6. -6. -3. -2. -2. -2. -1. -0. 1. 0. -1. -3. -5. -4. 200/250 MB TEMP. -0. -0. -1. -1. -2. -2. -3. -3. -3. -4. -4. -5. -5. -6. -6. -6. THETA_E EXCESS 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 0. 0. -0. -0. -0. -1. 700-500 MB RH -0. -0. -0. -0. -1. -1. -2. -3. -3. -4. -4. -4. -5. -5. -6. -5. MODEL VTX TENDENCY -0. -1. -1. -1. -5. -15. -24. -26. -28. -29. -30. -30. -30. -29. -28. -27. 850 MB ENV VORTICITY -0. -0. -0. -0. -0. -0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 1. 200 MB DIVERGENCE -0. -0. -0. -1. -1. -1. -1. -1. -1. -0. -0. 0. 0. 0. 1. 1. 850-700 T ADVEC 0. -0. -0. -0. -0. -1. -1. -1. -1. -0. -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. 0. 0. 0. GOES PREDICTORS 0. 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 0. 0. 0. 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. -2. -1. -0. 0. 1. 2. 2. 2. 2. 2. ------------------------------------------------------------------------------ TOTAL CHANGE -3. -3. -2. 1. 2. -0. -3. 0. 5. 8. 13. 17. 20. 19. 20. 21. CURRENT MAX WIND (KT): 50. LAT, LON: 20.5 89.5 ** 2021 ATLANTIC RI INDEX AL072021 GRACE 08/19/21 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) : -20.0 -49.5 to 33.0 0.36 1.4 850-200 MB SHEAR (KT) : 9.7 30.1 to 2.3 0.73 1.4 HEAT CONTENT (KJ/CM2) : 32.6 0.0 to 151.8 0.21 0.4 STD DEV OF IR BR TEMP : 18.8 36.6 to 2.8 0.53 1.0 MAXIMUM WIND (KT) : 50.0 22.5 to 137.5 0.72 1.1 BL DRY-AIR FLUX (W/M2) : 242.0 895.4 to -55.0 0.69 1.1 2nd PC OF IR BR TEMP : 0.4 2.9 to -2.9 0.43 0.5 POT = MPI-VMAX (KT) : 113.9 28.3 to 146.3 0.73 0.5 D200 (10**7s-1) : 13.0 -29.7 to 185.9 0.20 0.1 %area of TPW <45 mm upshear : 19.0 100.0 to 0.0 0.81 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 2% is 0.4 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 11% is 1.0 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 8% is 1.1 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= 6% is 2.3 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= 0% is 0.0 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 0% is 0.0 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: 2.0% 11.4% 7.5% 6.9% 5.6% 9.6% 0.0% 0.0% Logistic: 1.5% 7.3% 4.6% 3.0% 2.3% 3.1% 7.8% 10.1% Bayesian: 0.4% 2.3% 0.6% 0.1% 0.1% 0.0% 0.0% 0.4% Consensus: 1.3% 7.0% 4.2% 3.3% 2.6% 4.2% 2.6% 3.5% DTOPS: 3.0% 9.0% 4.0% 0.0% 1.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/19/21 18 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 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) 50 50 50 50 53 46 33 29 27 27 27 27 27 27 27 27 27 18HR AGO 50 49 49 49 52 45 32 28 26 26 26 26 26 26 26 26 26 12HR AGO 50 47 46 46 49 42 29 25 23 23 23 23 23 23 23 23 23 6HR AGO 50 44 41 40 43 36 23 19 17 17 17 17 17 17 17 17 17 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT