* GFS version * * ATLANTIC 2021 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * INVEST AL982021 08/27/21 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 25 25 24 24 25 27 28 30 29 30 31 31 33 35 36 36 37 V (KT) LAND 25 25 24 24 25 27 28 30 29 30 31 31 33 35 36 36 37 V (KT) LGEM 25 25 25 24 24 23 23 23 23 24 25 26 25 24 22 21 20 Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP SHEAR (KT) 13 10 13 16 13 10 16 13 16 16 25 31 26 33 41 40 21 SHEAR ADJ (KT) 4 4 4 4 0 -1 -1 0 -3 0 -1 3 3 1 -2 -1 3 SHEAR DIR 267 266 271 293 302 307 353 1 358 315 302 288 299 307 337 329 322 SST (C) 27.6 27.6 27.7 27.7 27.7 27.6 27.5 27.4 27.4 27.4 27.4 27.3 27.8 27.8 28.2 28.3 29.0 POT. INT. (KT) 132 130 130 129 128 127 127 127 127 126 126 127 135 136 141 143 153 ADJ. POT. INT. 129 124 122 119 117 116 118 117 118 113 114 118 127 131 136 135 143 200 MB T (C) -53.5 -53.5 -53.7 -53.8 -53.7 -53.7 -53.8 -53.8 -54.1 -54.4 -54.6 -54.8 -55.0 -55.2 -55.4 -55.7 -55.8 200 MB VXT (C) 0.0 0.0 0.0 0.1 0.2 0.3 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 TH_E DEV (C) 8 8 8 8 9 9 9 9 8 8 8 8 9 10 10 11 11 700-500 MB RH 59 59 55 52 52 53 48 49 51 48 42 39 38 40 42 48 56 MODEL VTX (KT) 13 12 12 12 11 11 8 6 2 LOST LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 34 35 19 4 0 -18 -35 -40 -52 -61 -60 -48 -36 -37 -40 -74 -110 200 MB DIV 11 -6 -10 -19 -2 -14 1 -22 -20 -16 -15 -12 16 5 -22 22 6 700-850 TADV -1 0 1 2 3 1 1 0 -1 -2 1 7 11 15 22 21 20 LAND (KM) 1031 1009 981 952 954 970 1036 1134 1262 1373 1426 1417 1290 1141 828 621 681 LAT (DEG N) 13.4 13.6 13.6 13.5 13.6 13.8 14.4 15.2 16.2 17.0 17.6 18.1 18.7 xx.x xx.x xx.x xx.x LONG(DEG W) 48.5 49.4 50.0 50.4 50.6 50.7 50.6 50.2 49.6 48.9 49.1 50.2 52.2 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 11 7 5 3 1 2 4 5 6 3 4 8 11 15 15 14 14 HEAT CONTENT 20 26 30 31 30 29 27 21 17 21 22 23 46 23 46 22 46 FORECAST TRACK FROM TABM INITIAL HEADING/SPEED (DEG/KT):280/ 13 CX,CY: -12/ 2 T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 767 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 17.6 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 36.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 1.7 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. 1. 1. 4. 8. 14. 18. 22. 25. 27. 29. 31. 32. 32. 32. VERTICAL SHEAR MAG 1. 2. 3. 3. 5. 5. 4. 3. 2. -2. -4. -7. -10. -14. -18. -19. VERTICAL SHEAR ADJ -0. -1. -1. -1. -1. -0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 0. VERTICAL SHEAR DIR -0. -1. -1. -1. -2. -2. -1. -1. -0. -1. -1. -1. -2. -2. -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. -1. -0. -0. -0. 0. 1. 1. 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. -1. -1. -2. -3. -7. -12. -17. -20. -21. -22. -22. -22. -22. -21. -20. 850 MB ENV VORTICITY 0. 0. -0. -0. -0. -1. -1. -2. -2. -3. -3. -4. -4. -4. -5. -6. 200 MB DIVERGENCE -0. -0. -1. -1. -2. -2. -2. -3. -3. -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. 1. 1. 1. 1. 1. 2. 2. 2. 2. 2. 2. 2. STEERING LEVEL PRES -0. -0. -0. -1. -1. -1. -1. -1. -2. -2. -3. -3. -2. -2. -2. -3. DAYS FROM CLIM. PEAK 0. -0. -0. -0. 0. 0. 0. 0. 0. -0. -0. -0. -0. -0. -0. -0. GOES PREDICTORS -0. -1. -0. -1. -1. -2. -3. -4. -4. -4. -4. -4. -4. -4. -4. -3. 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 -0. -1. -1. -0. 2. 3. 5. 4. 5. 6. 6. 8. 10. 11. 11. 12. CURRENT MAX WIND (KT): 25. LAT, LON: 13.4 48.5 ** 2021 ATLANTIC RI INDEX AL982021 INVEST 08/27/21 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) : 0.0 -49.5 to 33.0 0.60 2.2 850-200 MB SHEAR (KT) : 13.0 30.1 to 2.3 0.61 1.0 HEAT CONTENT (KJ/CM2) : 27.4 0.0 to 151.8 0.18 0.3 STD DEV OF IR BR TEMP : 17.6 36.6 to 2.8 0.56 1.0 MAXIMUM WIND (KT) : 25.0 22.5 to 137.5 0.07 0.1 BL DRY-AIR FLUX (W/M2) : 144.2 895.4 to -55.0 0.79 1.1 2nd PC OF IR BR TEMP : 1.1 2.9 to -2.9 0.31 0.3 POT = MPI-VMAX (KT) : 97.2 28.3 to 146.3 0.58 0.4 D200 (10**7s-1) : -5.2 -29.7 to 185.9 0.11 0.1 %area of TPW <45 mm upshear : 8.3 100.0 to 0.0 0.92 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= 9% is 0.8 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 7% is 1.0 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 1.5 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: 3.1% 8.7% 6.5% 6.3% 0.0% 0.0% 7.1% 0.0% Logistic: 1.7% 4.7% 3.5% 2.2% 0.5% 3.9% 2.6% 4.2% Bayesian: 0.1% 0.2% 0.2% 0.0% 0.0% 0.0% 0.0% 0.0% Consensus: 1.7% 4.5% 3.4% 2.8% 0.2% 1.3% 3.2% 1.4% DTOPS: 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL982021 INVEST 08/27/21 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 AL982021 INVEST 08/27/2021 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) 25 25 24 24 25 27 28 30 29 30 31 31 33 35 36 36 37 18HR AGO 25 24 23 23 24 26 27 29 28 29 30 30 32 34 35 35 36 12HR AGO 25 22 21 21 22 24 25 27 26 27 28 28 30 32 33 33 34 6HR AGO 25 19 16 15 16 18 19 21 20 21 22 22 24 26 27 27 28 NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR INTENSITY IN 12HR < 83 KT