* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * GRACE AL072021 08/17/21 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 35 39 43 48 52 61 72 76 81 79 75 65 65 68 70 73 74 V (KT) LAND 35 39 43 48 52 61 72 43 52 51 47 33 29 27 27 27 27 V (KT) LGEM 35 38 41 44 48 56 67 41 53 60 62 41 31 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) 10 12 8 7 11 6 12 14 10 16 21 12 6 N/A N/A N/A N/A SHEAR ADJ (KT) 1 0 0 0 -3 -1 -1 -2 3 3 1 7 15 N/A N/A N/A N/A SHEAR DIR 286 292 280 266 312 348 327 19 354 12 349 8 358 N/A N/A N/A N/A SST (C) 29.4 29.7 30.1 30.0 29.8 29.9 29.6 29.7 30.0 30.3 30.0 29.9 29.1 N/A N/A N/A N/A POT. INT. (KT) 160 165 173 172 168 170 164 166 171 171 169 168 154 N/A N/A N/A N/A ADJ. POT. INT. 157 163 172 171 166 167 159 160 163 162 155 155 142 N/A N/A N/A N/A 200 MB T (C) -53.3 -53.4 -53.2 -53.0 -53.2 -52.7 -52.8 -52.4 -52.3 -52.1 -52.0 -51.9 -51.6 N/A N/A N/A N/A 200 MB VXT (C) 0.2 0.4 0.2 0.5 0.6 0.4 0.8 0.7 0.7 0.6 0.9 0.7 0.0 N/A N/A N/A N/A TH_E DEV (C) 12 11 11 10 10 11 10 11 10 11 10 12 10 N/A N/A N/A N/A 700-500 MB RH 54 54 58 58 55 56 54 56 57 62 66 69 71 N/A N/A N/A N/A MODEL VTX (KT) 9 10 12 13 13 15 18 18 19 19 16 8 LOST LOST LOST LOST LOST 850 MB ENV VOR 9 6 18 17 -2 -7 -18 -15 13 18 40 48 64 N/A N/A N/A N/A 200 MB DIV 26 18 25 35 18 32 21 7 11 14 16 33 44 N/A N/A N/A N/A 700-850 TADV -4 -9 -8 -15 -18 -9 -13 -10 -14 -4 -8 -7 1 N/A N/A N/A N/A LAND (KM) 40 26 7 116 282 234 22 -3 293 186 29 -139 -382 N/A N/A N/A N/A LAT (DEG N) 18.0 18.3 18.5 18.8 19.1 19.7 20.3 21.0 21.4 21.7 21.9 22.1 22.2 N/A N/A N/A N/A LONG(DEG W) 74.7 76.2 77.6 79.2 80.8 84.0 87.1 90.2 93.1 95.4 97.2 99.2 101.6 N/A N/A N/A N/A STM SPEED (KT) 14 14 14 15 15 15 14 14 13 9 9 10 11 N/A N/A N/A N/A HEAT CONTENT 40 50 65 83 87 94 34 38 37 40 29 30 17 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: 30 PRESSURE OF STEERING LEVEL (MB): 611 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 18.0 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 72.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 36.6 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. -1. -0. 2. 7. 13. 18. 23. 26. 31. 36. 40. 42. 44. 43. VERTICAL SHEAR MAG 1. 2. 3. 3. 5. 6. 6. 7. 6. 4. 3. 3. 3. 3. 3. 4. VERTICAL SHEAR ADJ -0. 0. 0. 0. 1. 2. 2. 2. 1. 1. 0. -0. -0. -0. -0. -0. VERTICAL SHEAR DIR -0. -0. -1. -1. -1. -1. -1. -0. 0. 1. 1. 1. 1. 1. 1. 1. PERSISTENCE 1. 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 200/250 MB TEMP. -0. -0. -1. -1. -1. -1. -2. -2. -2. -2. -3. -3. -4. -4. -4. -4. 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. -2. -2. -3. -3. -4. -4. -4. MODEL VTX TENDENCY 0. 1. 2. 2. 3. 7. 7. 9. 7. 3. -9. -12. -13. -13. -12. -12. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1. 200 MB DIVERGENCE -0. -0. -0. -0. -0. -0. -1. -1. -1. -1. -0. 0. 0. 0. 1. 1. 850-700 T ADVEC 0. -0. -0. -0. -1. -1. -2. -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. 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 0. 1. 1. 1. 0. 0. -0. -0. -0. -0. -1. -0. -0. 0. 0. 0. OCEAN HEAT CONTENT 0. 0. 0. -0. -1. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL 1. 3. 5. 7. 11. 10. 7. 4. 1. -2. -4. -6. -7. -7. -8. -8. ------------------------------------------------------------------------------ TOTAL CHANGE 4. 8. 13. 17. 26. 38. 41. 46. 44. 40. 30. 30. 33. 35. 38. 39. CURRENT MAX WIND (KT): 35. LAT, LON: 18.0 74.7 ** 2021 ATLANTIC RI INDEX AL072021 GRACE 08/17/21 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) : 9.7 30.1 to 2.3 0.74 1.7 HEAT CONTENT (KJ/CM2) : 65.0 0.0 to 151.8 0.43 0.9 STD DEV OF IR BR TEMP : 18.0 36.6 to 2.8 0.55 1.3 MAXIMUM WIND (KT) : 35.0 22.5 to 137.5 0.33 0.6 BL DRY-AIR FLUX (W/M2) : 225.6 895.4 to -55.0 0.70 1.4 2nd PC OF IR BR TEMP : 0.4 2.9 to -2.9 0.43 0.6 POT = MPI-VMAX (KT) : 130.8 28.3 to 146.3 0.87 0.8 D200 (10**7s-1) : 24.4 -29.7 to 185.9 0.25 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= 6% is 1.2 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 22% is 2.0 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= 9% is 2.4 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 7% is 3.0 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 11% is 2.5 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 19% is 4.1 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 28% is 5.3 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: 5.9% 21.9% 11.1% 9.3% 7.1% 11.4% 19.1% 28.1% Logistic: 12.7% 45.6% 32.8% 27.5% 18.2% 45.2% 47.1% 60.6% Bayesian: 3.6% 30.3% 14.0% 1.1% 0.9% 6.6% 7.1% 6.9% Consensus: 7.4% 32.6% 19.3% 12.7% 8.8% 21.1% 24.4% 31.9% DTOPS: 2.0% 13.0% 8.0% 5.0% 0.0% 5.0% 2.0% 1.0% ## ANNULAR HURRICANE INDEX (AHI) AL072021 GRACE 08/17/21 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 08/17/2021 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) 35 39 43 48 52 61 72 43 52 51 47 33 29 27 27 27 27 18HR AGO 35 34 38 43 47 56 67 38 47 46 42 28 24 22 22 22 22 12HR AGO 35 32 31 36 40 49 60 31 40 39 35 21 17 15 15 15 15 6HR AGO 35 29 26 25 29 38 49 20 29 28 24 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