* GFS version * * ATLANTIC 2023 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * IDALIA AL102023 08/31/23 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 55 54 53 52 48 42 37 35 35 31 23 20 23 18 20 19 19 V (KT) LAND 55 54 53 52 48 42 37 35 35 31 23 20 23 18 20 19 19 V (KT) LGEM 55 55 53 50 47 42 40 40 39 34 29 24 21 18 16 N/A N/A Storm Type TROP TROP EXTP TROP TROP TROP TROP TROP TROP TROP TROP TROP EXTP EXTP TROP TROP SUBT SHEAR (KT) 21 22 20 19 11 14 26 35 47 57 58 58 47 34 26 16 17 SHEAR ADJ (KT) 8 8 3 0 1 -2 -3 2 0 -4 -3 -6 -5 -9 -6 -1 -1 SHEAR DIR 221 212 217 222 221 243 251 236 226 222 220 218 211 224 221 232 200 SST (C) 29.5 28.9 28.3 27.4 26.7 28.3 29.0 29.1 28.8 28.2 28.0 27.7 27.4 27.7 28.1 28.1 25.1 POT. INT. (KT) 163 152 142 130 121 139 149 152 148 139 136 131 127 130 136 137 106 200 MB T (C) -48.5 -48.3 -48.5 -48.8 -49.0 -49.7 -50.1 -50.6 -51.1 -51.2 -51.4 -52.3 -52.3 -52.9 -53.1 -52.8 -53.0 200 MB VXT (C) 0.3 0.2 0.2 0.1 0.2 0.4 0.3 0.8 0.5 0.4 0.4 0.2 1.2 0.7 1.1 0.7 0.9 TH_E DEV (C) 4 3 3 4 4 4 5 5 5 6 6 5 4 4 4 3 5 700-500 MB RH 53 50 45 41 41 40 39 39 36 37 38 38 37 34 30 33 37 MODEL VTX (KT) 24 23 22 22 20 18 18 19 21 20 19 18 22 19 20 18 18 850 MB ENV VOR 6 -11 0 24 27 46 48 41 47 44 31 25 36 33 21 -6 6 200 MB DIV 7 -17 2 7 -4 -15 2 31 58 5 21 24 0 -25 9 -3 27 700-850 TADV -23 -39 -44 -39 -16 -12 -3 -1 1 -2 1 -2 0 1 5 0 1 LAND (KM) 231 372 512 651 791 949 1015 1073 1152 1138 1046 922 789 700 659 571 362 LAT (DEG N) 33.6 33.4 33.2 32.7 32.1 31.2 30.9 31.3 32.3 33.5 34.9 36.3 37.4 xx.x xx.x xx.x xx.x LONG(DEG W) 74.4 72.7 71.0 69.6 68.3 67.0 66.4 65.4 63.9 62.2 60.7 60.2 60.8 xxx.x xxx.x xxx.x xxx.x STM SPEED (KT) 16 14 13 13 10 5 3 7 9 9 8 7 5 5 6 8 10 HEAT CONTENT 69 29 16 9 6 24 30 31 20 15 14 16 15 24 34 20 0 FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT): 90/ 18 CX,CY: 18/ 0 T-12 MAX WIND: 50 PRESSURE OF STEERING LEVEL (MB): 563 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 6.3 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 0.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 7.1 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. 7. 9. 10. 10. 11. 11. 12. 13. 14. 15. 16. SST POTENTIAL 1. 2. 2. 2. 0. -1. -2. -3. -5. -8. -11. -14. -18. -21. -25. -28. VERTICAL SHEAR MAG -0. -0. 0. 1. 2. 2. 0. -2. -5. -7. -7. -5. -3. -2. 1. 4. VERTICAL SHEAR ADJ -0. -1. -1. -1. -1. -0. -0. -0. 1. 1. 1. 2. 2. 1. 1. 1. VERTICAL SHEAR DIR 0. 0. 1. 1. 1. 2. 2. 2. 1. 1. 1. 1. 1. 1. -1. -1. PERSISTENCE 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 200/250 MB TEMP. -1. -2. -3. -4. -6. -6. -5. -5. -4. -4. -4. -5. -5. -3. -1. -1. THETA_E EXCESS -0. -1. -1. -1. -2. -3. -3. -3. -2. -2. -1. -2. -2. -2. -1. -1. 700-500 MB RH 0. 0. 0. 1. 1. 2. 3. 4. 5. 6. 6. 6. 6. 6. 6. 4. MODEL VTX TENDENCY -0. -1. -2. -3. -7. -9. -10. -8. -10. -14. -16. -11. -16. -16. -19. -19. 850 MB ENV VORTICITY -0. -0. -0. -0. -0. 0. 0. 0. 0. 0. 1. 1. 1. 1. 1. 1. 200 MB DIVERGENCE -0. -0. -1. -1. -1. -1. -1. -1. -1. 0. 1. 1. 2. 3. 4. 4. 850-700 T ADVEC 0. -0. -1. -1. -3. -3. -3. -3. -3. -3. -2. -2. -2. -2. -1. -2. ZONAL STORM MOTION 0. -0. -1. -1. -3. -4. -4. -5. -5. -7. -9. -10. -10. -10. -11. -13. STEERING LEVEL PRES 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 0. 0. 0. 1. DAYS FROM CLIM. PEAK 0. -0. -0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. -0. -0. GOES PREDICTORS -1. -2. -1. -2. -2. -4. -5. -7. -7. -8. -8. -8. -8. -7. -6. -3. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -0. -0. -0. -1. -1. -0. -0. 0. 0. 0. RI POTENTIAL -0. -0. -0. -1. -1. -1. -1. -0. 0. 1. 1. 1. 1. 1. 2. 1. -------------------------------------------------------------------------------------------- TOTAL CHANGE -1. -2. -3. -7. -13. -18. -20. -20. -24. -32. -35. -32. -37. -35. -36. -36. CURRENT MAX WIND (KT): 55. LAT, LON: 33.6 74.4 ** 2023 ATLANTIC RI INDEX AL102023 IDALIA 08/31/23 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) : 5.0 -49.5 to 33.0 0.66 4.2 MULTI-LAYER SHEAR (KT) : 30.7 45.1 to 6.7 0.37 1.2 HEAT CONTENT (KJ/CM2) : 25.8 0.0 to 161.7 0.16 0.4 STD DEV OF IR BR TEMP : 6.3 36.6 to 2.8 0.90 2.3 MAXIMUM WIND (KT) : 55.0 22.5 to 126.5 0.86 1.3 2nd PC OF IR BR TEMP : 0.3 2.9 to -3.0 0.45 0.6 POT = MPI-VMAX (KT) : 67.9 27.0 to 144.1 0.35 0.3 D200 (10**7s-1) : -1.0 -30.8 to 188.1 0.14 0.2 BL DRY-AIR FLUX (W/M2) : 353.0 895.4 to -71.5 0.56 0.7 %area of TPW <45 mm upshear : 21.1 109.3 to 0.0 0.81 0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 7% is 1.4 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 16% is 1.5 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 11% is 1.7 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 10% is 2.1 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 8% is 3.8 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= 11% is 2.3 times climatological mean ( 4.7%) SHIPS Prob RI for 65kt/ 72hr RI threshold= 7% is 1.3 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: 7.1% 16.3% 11.4% 9.8% 7.5% 11.4% 10.8% 6.7% Logistic: 2.0% 2.1% 2.2% 1.0% 0.1% 0.3% 0.0% 0.0% Bayesian: 0.2% 0.0% 0.0% 0.1% 0.0% 0.0% 0.0% 0.0% Consensus: 3.1% 6.2% 4.5% 3.6% 2.5% 3.9% 3.6% 2.2% DTOPS: 1.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% ## ANNULAR HURRICANE INDEX (AHI) AL102023 IDALIA 08/31/23 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 AL102023 IDALIA 08/31/2023 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) 55 54 53 52 48 42 37 35 35 31 23 20 23 18 20 19 19 18HR AGO 55 54 53 52 48 42 37 35 35 31 23 20 23 18 20 19 19 12HR AGO 55 52 51 50 46 40 35 33 33 29 21 18 21 16 18 17 17 6HR AGO 55 49 46 45 41 35 30 28 28 24 16 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