* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/18/21 06 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 53 56 60 64 70 72 74 74 69 64 63 66 68 69 71 73 V (KT) LAND 50 53 56 60 64 42 43 45 45 32 28 27 30 33 34 36 38 V (KT) LGEM 50 53 57 61 65 43 45 50 55 35 29 27 30 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) 14 12 9 11 14 15 14 13 14 14 10 8 11 N/A N/A N/A N/A SHEAR ADJ (KT) -4 -1 0 -3 0 1 2 1 0 -4 1 1 4 N/A N/A N/A N/A SHEAR DIR 299 319 324 321 328 21 358 14 353 34 52 74 79 N/A N/A N/A N/A SST (C) 30.0 29.9 29.8 30.1 29.9 29.7 29.8 30.0 29.7 29.7 28.6 29.2 30.6 N/A N/A N/A N/A POT. INT. (KT) 171 170 168 173 170 165 167 170 164 164 145 155 172 N/A N/A N/A N/A ADJ. POT. INT. 169 169 165 171 166 160 158 161 154 153 134 145 172 N/A N/A N/A N/A 200 MB T (C) -53.0 -53.1 -52.7 -52.5 -52.7 -52.5 -52.5 -52.3 -52.2 -51.9 -52.0 -51.8 -51.6 N/A N/A N/A N/A 200 MB VXT (C) 0.9 0.8 0.6 0.5 0.6 0.7 0.6 0.2 0.8 0.9 0.5 0.2 0.0 N/A N/A N/A N/A TH_E DEV (C) 11 10 11 11 9 10 9 9 9 11 9 9 6 N/A N/A N/A N/A 700-500 MB RH 52 52 55 58 58 59 59 64 66 70 75 77 75 N/A N/A N/A N/A MODEL VTX (KT) 15 15 16 18 18 18 17 17 16 11 6 3 LOST LOST LOST LOST LOST 850 MB ENV VOR 3 -15 -9 -5 -18 -20 -15 15 53 68 77 76 69 N/A N/A N/A N/A 200 MB DIV 12 9 28 40 21 28 7 19 6 3 14 56 24 N/A N/A N/A N/A 700-850 TADV -5 -5 -7 -7 -13 -6 -13 -5 -8 -3 -9 -3 0 N/A N/A N/A N/A LAND (KM) 198 337 293 245 101 -100 186 239 13 -190 -320 -192 15 N/A N/A N/A N/A LAT (DEG N) 18.7 19.0 19.3 19.6 19.9 20.3 20.7 20.9 20.9 20.8 20.8 20.7 20.5 N/A N/A N/A N/A LONG(DEG W) 80.1 81.7 83.3 84.8 86.4 89.4 92.2 94.5 97.0 99.2 101.3 103.4 105.8 N/A N/A N/A N/A STM SPEED (KT) 14 15 15 15 15 14 12 12 11 10 10 11 11 N/A N/A N/A N/A HEAT CONTENT 85 86 83 87 48 5 27 42 28 6 13 18 32 N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):280/ 13 CX,CY: -12/ 2 T-12 MAX WIND: 45 PRESSURE OF STEERING LEVEL (MB): 545 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 22.1 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 51.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 27.2 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 1. 1. 2. 3. 5. 8. 12. 15. 18. 20. 23. 27. 29. 30. 31. 30. VERTICAL SHEAR MAG 0. 0. 1. 1. 1. 2. 2. 3. 2. 3. 3. 4. 4. 5. 5. 5. VERTICAL SHEAR ADJ 0. 0. 1. 1. 1. 1. 1. 1. 2. 2. 1. 1. 1. 1. 1. 1. VERTICAL SHEAR DIR -0. -0. -0. -0. 0. 1. 1. 2. 2. 3. 3. 4. 5. 5. 5. 4. PERSISTENCE 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 0. 200/250 MB TEMP. 0. -0. -0. -1. -1. -2. -2. -2. -3. -3. -3. -4. -4. -4. -4. -4. THETA_E EXCESS 0. 0. 0. 1. 1. 1. 1. 1. 0. 0. 0. 0. -0. -0. -0. -0. 700-500 MB RH 0. 0. 0. -0. -0. -1. -1. -2. -3. -3. -4. -5. -6. -6. -7. -6. MODEL VTX TENDENCY -0. 0. 1. 1. 1. -1. -0. -3. -11. -18. -23. -24. -23. -23. -22. -22. 850 MB ENV VORTICITY -0. -0. -0. -1. -1. -1. -2. -1. -1. -1. -0. -0. -0. -0. -0. -0. 200 MB DIVERGENCE -0. -0. -0. -0. -0. -1. -1. -1. -1. -1. -0. 0. 0. 0. 1. 1. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -0. -0. -0. -0. -0. -0. ZONAL STORM MOTION -0. -0. 0. 0. 1. 1. 1. 1. 1. 2. 2. 2. 2. 2. 2. 2. STEERING LEVEL PRES 0. 0. 0. 0. 1. 0. 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. DAYS FROM CLIM. PEAK -0. 0. 0. 0. -0. -0. -0. -0. -0. 0. 0. 0. 0. 0. 0. 0. GOES PREDICTORS -0. -1. -1. -1. -1. -1. -1. -1. -0. -0. -0. -1. -1. -2. -2. -1. OCEAN HEAT CONTENT -0. -0. -1. -1. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 1. 2. 3. 5. 7. 6. 4. 2. 0. -1. -3. -4. -4. -4. -5. -5. ------------------------------------------------------------------------------ TOTAL CHANGE 3. 6. 10. 14. 20. 22. 24. 24. 19. 14. 13. 16. 18. 19. 21. 23. CURRENT MAX WIND (KT): 50. LAT, LON: 18.7 80.1 ** 2021 ATLANTIC RI INDEX AL072021 GRACE 08/18/21 06 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 0.66 3.3 850-200 MB SHEAR (KT) : 12.1 30.1 to 2.3 0.65 1.5 HEAT CONTENT (KJ/CM2) : 77.8 0.0 to 151.8 0.51 1.1 STD DEV OF IR BR TEMP : 22.1 36.6 to 2.8 0.43 1.0 MAXIMUM WIND (KT) : 50.0 22.5 to 137.5 0.72 1.4 BL DRY-AIR FLUX (W/M2) : 313.6 895.4 to -55.0 0.61 1.2 2nd PC OF IR BR TEMP : 1.2 2.9 to -2.9 0.29 0.4 POT = MPI-VMAX (KT) : 118.1 28.3 to 146.3 0.76 0.7 D200 (10**7s-1) : 22.0 -29.7 to 185.9 0.24 0.2 %area of TPW <45 mm upshear : 3.0 100.0 to 0.0 0.97 0.2 SHIPS Prob RI for 20kt/ 12hr RI threshold= 7% is 1.5 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 21% is 1.9 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 11% is 1.6 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 10% is 2.5 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 7% is 3.1 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= 16% is 3.0 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: 7.1% 20.9% 11.0% 9.7% 7.5% 11.0% 12.2% 15.7% Logistic: 8.1% 24.3% 16.5% 16.3% 9.2% 17.2% 17.9% 28.1% Bayesian: 2.3% 16.2% 3.8% 0.2% 0.2% 2.9% 4.4% 6.1% Consensus: 5.8% 20.5% 10.4% 8.7% 5.6% 10.3% 11.5% 16.7% DTOPS: 9.0% 22.0% 17.0% 8.0% 3.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/18/21 06 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 08/18/2021 06 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 53 56 60 64 42 43 45 45 32 28 27 30 33 34 36 38 18HR AGO 50 49 52 56 60 38 39 41 41 28 24 23 26 29 30 32 34 12HR AGO 50 47 46 50 54 32 33 35 35 22 18 17 20 23 24 26 28 6HR AGO 50 44 41 40 44 22 23 25 25 DIS DIS DIS DIS DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT