* GFS version * * ATLANTIC 2024 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * HELENE AL092024 09/25/24 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 75 85 94 102 112 114 102 91 67 46 28 N/A N/A N/A N/A N/A N/A V (KT) LAND 75 85 94 102 112 71 41 31 28 28 27 N/A N/A N/A N/A N/A N/A V (KT) LGEM 75 85 95 104 112 73 41 31 28 28 27 N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP EXTP EXTP EXTP EXTP EXTP N/A N/A N/A N/A N/A N/A SHEAR (KT) 9 10 9 5 10 35 32 10 26 36 41 N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) 0 -1 -1 1 4 2 -1 2 0 -3 -4 N/A N/A N/A N/A N/A N/A SHEAR DIR 186 190 213 243 210 223 210 251 262 250 241 N/A N/A N/A N/A N/A N/A SST (C) 30.8 31.0 30.9 30.5 30.0 28.9 26.2 21.4 21.4 21.4 21.8 N/A N/A N/A N/A N/A N/A POT. INT. (KT) 172 172 173 174 173 154 117 81 78 80 82 N/A N/A N/A N/A N/A N/A 200 MB T (C) -50.6 -50.5 -50.5 -50.0 -48.9 -47.9 -48.0 -49.1 -50.1 -50.0 -50.2 N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 1.3 1.3 1.5 1.5 1.6 2.7 1.1 -0.1 0.7 1.3 0.7 N/A N/A N/A N/A N/A N/A TH_E DEV (C) 8 7 7 6 7 2 1 0 1 0 2 N/A N/A N/A N/A N/A N/A 700-500 MB RH 77 75 72 69 62 56 48 45 46 40 35 N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 29 32 34 35 39 39 30 26 18 13 10 LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 110 86 97 125 147 144 172 159 130 92 72 N/A N/A N/A N/A N/A N/A 200 MB DIV 128 109 104 88 102 77 79 27 18 -9 -6 N/A N/A N/A N/A N/A N/A 700-850 TADV 2 3 13 27 36 54 83 0 0 0 1 N/A N/A N/A N/A N/A N/A LAND (KM) 77 193 290 342 225 -234 -602 -685 -696 -685 -640 N/A N/A N/A N/A N/A N/A LAT (DEG N) 22.0 23.2 24.4 26.0 27.5 32.2 36.0 36.9 37.0 36.9 36.5 N/A N/A N/A N/A N/A N/A LONG(DEG W) 86.4 86.3 86.2 85.6 85.1 84.4 85.9 87.6 87.7 87.8 88.0 N/A N/A N/A N/A N/A N/A STM SPEED (KT) 11 12 14 16 20 21 14 4 0 2 2 N/A N/A N/A N/A N/A N/A HEAT CONTENT 50 60 73 46 29 6 5 5 5 6 6 N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):345/ 9 CX,CY: -1/ 9 T-12 MAX WIND: 55 PRESSURE OF STEERING LEVEL (MB): 638 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 10.3 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 99.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 59.9 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. 0. 0. 0. 0. 0. 0. SST POTENTIAL 2. 4. 5. 6. 5. 1. -5. -10. -15. -19. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR MAG -0. -0. 0. 0. -3. -5. -3. -3. -3. -3. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR ADJ 0. 0. 0. 0. -0. 0. 0. 1. 1. 2. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. -0. -0. 0. 1. 2. 2. 3. 4. 0. 0. 0. 0. 0. 0. PERSISTENCE 3. 4. 4. 4. 2. 2. 2. 1. 0. -1. 0. 0. 0. 0. 0. 0. 200/250 MB TEMP. -0. -1. -1. -2. -4. -5. -6. -6. -6. -6. 0. 0. 0. 0. 0. 0. THETA_E EXCESS -0. -0. -0. -0. -1. -2. -3. -4. -5. -6. 0. 0. 0. 0. 0. 0. 700-500 MB RH -0. -1. -1. -1. -2. -2. -2. -1. -1. -0. 0. 0. 0. 0. 0. 0. MODEL VTX TENDENCY 1. 2. 3. 7. 7. -1. -7. -20. -28. -35. 0. 0. 0. 0. 0. 0. 850 MB ENV VORTICITY 0. 1. 1. 1. 2. 3. 4. 4. 5. 5. 0. 0. 0. 0. 0. 0. 200 MB DIVERGENCE 0. 1. 2. 2. 2. 2. 2. 2. 2. 1. 0. 0. 0. 0. 0. 0. 850-700 T ADVEC 0. 0. 0. 0. 1. 4. 4. 3. 3. 2. 0. 0. 0. 0. 0. 0. ZONAL STORM MOTION 0. 0. -0. -0. -0. -0. -0. -0. -0. -1. 0. 0. 0. 0. 0. 0. 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. 0. 0. GOES PREDICTORS 1. 1. 1. 1. 1. 1. 1. 2. 2. 1. 0. 0. 0. 0. 0. 0. OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. 0. -0. -0. -0. 0. 0. 0. 0. 0. 0. RI POTENTIAL 2. 6. 10. 15. 22. 22. 17. 10. 3. -2. 0. 0. 0. 0. 0. 0. -------------------------------------------------------------------------------------------- TOTAL CHANGE 10. 19. 27. 37. 39. 27. 16. -8. -29. -47. 0. 0. 0. 0. 0. 0. CURRENT MAX WIND (KT): 75. LAT, LON: 22.0 86.4 ** 2024 ATLANTIC RI INDEX AL092024 HELENE 09/25/24 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) : 20.0 -49.5 to 33.0 0.84 18.3 MULTI-LAYER SHEAR (KT) : 17.8 46.9 to 6.8 0.73 8.1 HEAT CONTENT (KJ/CM2) : 51.6 0.0 to 155.1 0.33 3.0 STD DEV OF IR BR TEMP : 10.3 36.6 to 2.8 0.78 6.6 MAXIMUM WIND (KT) : 75.0 22.5 to 137.5 0.81 4.6 2nd PC OF IR BR TEMP : 0.2 2.9 to -3.0 0.46 2.2 BL DRY-AIR FLUX (W/M2) : 164.4 895.4 to -69.3 0.76 3.8 D200 (10**7s-1) : 106.2 -29.7 to 189.2 0.62 2.8 POT = MPI-VMAX (KT) : 96.0 27.0 to 143.0 0.60 1.6 %area of TPW <45 mm upshear : 5.7 109.2 to 0.0 0.95 -0.2 SHIPS Prob RI for 20kt/ 12hr RI threshold= 27% is 5.6 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 68% is 6.2 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 51% is 7.4 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 37% is 9.5 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 20% is 8.2 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 23% is 5.0 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 12% is 2.7 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: 27.2% 67.8% 50.7% 37.2% 19.7% 23.1% 12.5% 0.0% Logistic: 35.0% 61.1% 50.3% 30.2% 9.7% 3.1% 0.1% 0.0% Bayesian: 47.5% 10.3% 15.3% 28.6% 14.4% 0.8% 0.0% 0.0% Consensus: 36.6% 46.4% 38.8% 32.0% 14.6% 9.0% 4.2% 0.0% DTOPS: 74.0% 99.0% 99.0% 91.0% 71.0% 2.0% 0.0% 1.0% SDCON: 55.3% 72.7% 68.9% 61.5% 42.8% 5.5% 2.1% .5% ## ANNULAR HURRICANE INDEX (AHI) AL092024 HELENE 09/25/24 18 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=2 NFAIL=5 ## ## 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 AL092024 HELENE 09/25/2024 18 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 5 16( 20) 30( 44) 0( 44) <-- PROB BASED ON INTENSITY ONLY PROB(%) 11 1( 12) 5( 16) 0( 16) <-- 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) 75 85 94 102 112 71 41 31 28 28 27 DIS DIS DIS DIS DIS DIS 18HR AGO 75 74 83 91 101 60 30 20 17 17 16 DIS DIS DIS DIS DIS DIS 12HR AGO 75 72 71 79 89 48 18 DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS 6HR AGO 75 69 66 65 75 34 DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR 75 85 76 70 67 37 DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS IN 12HR 75 85 94 85 79 75 45 35 32 32 31 DIS DIS DIS DIS DIS DIS