* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * INVEST AL982021 08/28/21 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 25 24 24 24 24 25 27 28 28 28 29 30 32 34 35 35 37 V (KT) LAND 25 24 24 24 24 25 27 28 28 28 29 30 32 34 35 35 37 V (KT) LGEM 25 25 24 24 23 22 21 21 22 23 24 25 25 24 23 22 21 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 12 15 17 13 11 15 12 19 16 22 20 28 22 33 39 35 25 SHEAR ADJ (KT) 4 6 6 0 -1 -2 -1 0 -6 0 1 2 3 5 0 6 7 SHEAR DIR 259 272 286 288 290 323 356 347 356 317 302 298 299 325 337 319 332 SST (C) 27.6 27.6 27.6 27.6 27.7 27.7 27.5 27.3 27.2 27.3 27.2 27.5 27.4 28.2 28.4 28.5 29.0 POT. INT. (KT) 131 130 129 128 129 129 127 125 124 124 124 129 130 141 144 145 153 ADJ. POT. INT. 127 124 120 118 118 118 117 116 114 111 113 120 124 138 140 140 144 200 MB T (C) -53.5 -53.7 -53.8 -53.7 -53.6 -53.8 -53.8 -54.0 -54.2 -54.6 -54.6 -54.8 -55.0 -55.2 -55.2 -55.6 -55.3 200 MB VXT (C) 0.0 0.0 0.1 0.2 0.2 0.2 0.0 0.0 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 TH_E DEV (C) 8 8 8 9 9 8 9 8 8 8 9 9 10 10 11 11 12 700-500 MB RH 58 54 52 51 53 50 50 51 54 47 43 38 38 39 41 54 62 MODEL VTX (KT) 12 12 12 11 11 10 7 5 3 LOST LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 33 19 6 1 0 -24 -31 -38 -52 -64 -55 -39 -33 -27 -31 -48 -84 200 MB DIV -18 -19 -17 0 0 19 -14 -11 -12 -19 -12 -19 24 -6 6 5 -3 700-850 TADV 0 1 2 3 1 1 1 0 -1 0 0 3 5 13 15 20 21 LAND (KM) 1025 1003 969 955 948 961 1029 1112 1228 1302 1301 1197 1045 877 561 308 374 LAT (DEG N) 13.8 14.0 13.9 13.9 13.9 14.1 14.7 15.4 16.3 16.9 17.2 17.5 17.7 xx.x xx.x xx.x xx.x LONG(DEG W) 49.5 50.4 51.0 51.4 51.6 51.9 51.8 51.5 50.8 50.5 50.9 52.3 54.4 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 10 7 5 3 2 2 4 5 5 3 4 8 12 15 15 14 13 HEAT CONTENT 25 28 28 27 26 24 24 21 16 16 18 41 21 53 50 36 43 FORECAST TRACK FROM TABM INITIAL HEADING/SPEED (DEG/KT):285/ 11 CX,CY: -10/ 3 T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 726 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 16.5 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 12.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 1.5 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. 0. 1. 1. 4. 8. 14. 18. 22. 25. 26. 28. 30. 31. 32. 32. VERTICAL SHEAR MAG 1. 2. 2. 3. 5. 5. 4. 2. 0. -3. -5. -6. -9. -13. -17. -18. VERTICAL SHEAR ADJ -0. -1. -1. -1. -0. 0. 0. 1. 2. 1. 1. 1. 0. 0. 0. -0. VERTICAL SHEAR DIR -0. -1. -1. -1. -2. -2. -1. -1. -1. -1. -1. -1. -2. -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. -0. -1. -1. -1. -1. -0. -0. -0. 0. 0. 1. 2. 3. 4. 5. THETA_E EXCESS -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. 0. -0. -0. -0. 700-500 MB RH -0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 2. 2. 2. 2. 2. MODEL VTX TENDENCY -0. -0. -1. -2. -3. -8. -12. -16. -18. -20. -21. -21. -21. -20. -20. -19. 850 MB ENV VORTICITY -0. -0. -0. -0. -1. -1. -2. -2. -3. -3. -4. -4. -4. -4. -5. -6. 200 MB DIVERGENCE -0. -1. -1. -1. -1. -2. -2. -2. -2. -2. -1. 0. 1. 1. 2. 3. 850-700 T ADVEC 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -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. -1. -1. -1. -0. -1. -1. -2. -2. -2. -2. -1. -1. -2. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. GOES PREDICTORS -1. -1. -1. -2. -2. -3. -5. -6. -6. -6. -6. -7. -7. -6. -6. -4. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. -0. -0. -0. RI POTENTIAL -0. -1. -1. -2. -3. -3. -2. -1. -0. 1. 2. 2. 3. 3. 3. 3. ------------------------------------------------------------------------------ TOTAL CHANGE -1. -1. -1. -1. 0. 2. 3. 3. 3. 4. 5. 7. 9. 10. 10. 12. CURRENT MAX WIND (KT): 25. LAT, LON: 13.8 49.5 ** 2021 ATLANTIC RI INDEX AL982021 INVEST 08/28/21 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) : 0.0 -49.5 to 33.0 0.60 2.1 850-200 MB SHEAR (KT) : 13.7 30.1 to 2.3 0.59 1.0 HEAT CONTENT (KJ/CM2) : 26.8 0.0 to 151.8 0.18 0.3 STD DEV OF IR BR TEMP : 16.5 36.6 to 2.8 0.59 1.0 MAXIMUM WIND (KT) : 25.0 22.5 to 137.5 0.07 0.1 BL DRY-AIR FLUX (W/M2) : 155.4 895.4 to -55.0 0.78 1.1 2nd PC OF IR BR TEMP : 1.5 2.9 to -2.9 0.25 0.2 POT = MPI-VMAX (KT) : 96.4 28.3 to 146.3 0.58 0.4 D200 (10**7s-1) : -10.8 -29.7 to 185.9 0.09 0.1 %area of TPW <45 mm upshear : 2.8 100.0 to 0.0 0.97 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 3% is 0.6 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 8% is 0.7 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 6% is 0.9 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 6% is 1.6 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 0% is 0.0 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 0% is 0.0 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 7% is 1.4 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: 3.0% 8.0% 6.3% 6.2% 0.0% 0.0% 6.8% 0.0% Logistic: 0.9% 1.5% 1.3% 0.6% 0.1% 0.7% 0.5% 0.8% Bayesian: 0.1% 0.0% 0.1% 0.0% 0.0% 0.0% 0.0% 0.0% Consensus: 1.3% 3.2% 2.5% 2.3% 0.0% 0.2% 2.4% 0.3% DTOPS: 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL982021 INVEST 08/28/21 00 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=5 NFAIL=2 ## ## 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 AL982021 INVEST 08/28/2021 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) 25 24 24 24 24 25 27 28 28 28 29 30 32 34 35 35 37 18HR AGO 25 24 24 24 24 25 27 28 28 28 29 30 32 34 35 35 37 12HR AGO 25 22 21 21 21 22 24 25 25 25 26 27 29 31 32 32 34 6HR AGO 25 19 16 15 15 16 18 19 19 19 20 21 23 25 26 26 28 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT