* GFS version * * ATLANTIC 2024 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * HELENE AL092024 09/25/24 12 UTC * TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120 132 144 156 168 V (KT) NO LAND 60 68 77 87 98 110 104 87 70 47 31 N/A N/A N/A N/A N/A N/A V (KT) LAND 60 68 77 87 98 110 53 35 29 28 27 N/A N/A N/A N/A N/A N/A V (KT) LGEM 60 66 73 82 91 105 52 34 29 28 27 N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP TROP TROP TROP EXTP EXTP EXTP N/A N/A N/A N/A N/A N/A SHEAR (KT) 7 11 11 5 4 20 34 24 18 33 40 N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) -1 0 -1 1 0 7 7 -1 5 0 -1 N/A N/A N/A N/A N/A N/A SHEAR DIR 211 189 194 228 247 214 228 183 269 248 250 N/A N/A N/A N/A N/A N/A SST (C) 31.0 30.9 31.0 30.9 30.5 29.1 26.4 21.7 21.4 21.4 21.9 N/A N/A N/A N/A N/A N/A POT. INT. (KT) 171 171 172 173 174 158 121 86 81 81 84 N/A N/A N/A N/A N/A N/A 200 MB T (C) -51.2 -50.7 -50.5 -50.4 -49.9 -48.7 -48.4 -48.6 -49.7 -49.6 -49.9 N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 1.1 1.1 0.8 1.1 1.4 2.1 1.6 0.5 0.1 1.5 1.4 N/A N/A N/A N/A N/A N/A TH_E DEV (C) 6 7 7 7 7 5 0 0 0 0 0 N/A N/A N/A N/A N/A N/A 700-500 MB RH 78 78 77 73 69 58 56 41 44 45 40 N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 27 29 30 32 35 39 33 25 20 13 11 LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 113 109 94 93 128 143 151 141 126 112 84 N/A N/A N/A N/A N/A N/A 200 MB DIV 102 122 107 121 102 76 87 48 -1 6 -12 N/A N/A N/A N/A N/A N/A 700-850 TADV 1 2 5 14 19 42 64 0 11 -2 -1 N/A N/A N/A N/A N/A N/A LAND (KM) 57 83 159 264 356 42 -382 -698 -686 -653 -644 N/A N/A N/A N/A N/A N/A LAT (DEG N) 21.1 22.0 22.9 24.3 25.6 29.6 34.3 36.9 36.9 36.6 36.5 N/A N/A N/A N/A N/A N/A LONG(DEG W) 86.2 86.3 86.4 86.0 85.6 84.3 84.4 86.5 88.6 88.6 87.2 N/A N/A N/A N/A N/A N/A STM SPEED (KT) 9 9 12 14 17 22 19 11 4 3 6 N/A N/A N/A N/A N/A N/A HEAT CONTENT 71 54 54 75 52 24 5 5 6 6 5 N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):325/ 9 CX,CY: -4/ 7 T-12 MAX WIND: 50 PRESSURE OF STEERING LEVEL (MB): 670 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 5.3 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 100.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 71.4 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 1. 3. 4. 4. 5. 4. 2. 0. -2. -4. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR MAG 0. 0. 1. 2. 2. 0. -0. 0. 0. -1. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR ADJ 0. 0. 0. 0. -0. -1. -1. -1. -1. -1. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. -0. -0. -0. 0. 1. 2. 3. 3. 0. 0. 0. 0. 0. 0. PERSISTENCE 2. 2. 2. 2. 1. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 200/250 MB TEMP. -0. -1. -1. -2. -3. -5. -5. -6. -6. -6. 0. 0. 0. 0. 0. 0. THETA_E EXCESS -0. -0. -0. -0. -1. -2. -3. -4. -5. -5. 0. 0. 0. 0. 0. 0. 700-500 MB RH -0. -1. -1. -2. -2. -3. -3. -2. -2. -1. 0. 0. 0. 0. 0. 0. MODEL VTX TENDENCY 1. 2. 3. 6. 9. 5. -5. -13. -24. -29. 0. 0. 0. 0. 0. 0. 850 MB ENV VORTICITY 0. 1. 1. 1. 2. 3. 4. 4. 4. 4. 0. 0. 0. 0. 0. 0. 200 MB DIVERGENCE 0. 1. 2. 2. 3. 3. 3. 2. 2. 1. 0. 0. 0. 0. 0. 0. 850-700 T ADVEC 0. 0. 0. 0. 1. 3. 5. 4. 3. 3. 0. 0. 0. 0. 0. 0. ZONAL STORM MOTION -0. -0. 0. 0. 0. 0. -0. -0. -0. -0. 0. 0. 0. 0. 0. 0. STEERING LEVEL PRES -0. -0. -0. -0. -1. -0. -0. -0. -1. -1. 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. 2. 2. 2. 1. 0. 0. 0. -0. -0. 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 3. 7. 12. 18. 27. 27. 21. 12. 4. -3. 0. 0. 0. 0. 0. 0. -------------------------------------------------------------------------------------------- TOTAL CHANGE 8. 17. 27. 38. 50. 44. 27. 10. -13. -29. 0. 0. 0. 0. 0. 0. CURRENT MAX WIND (KT): 60. LAT, LON: 21.1 86.2 ** 2024 ATLANTIC RI INDEX AL092024 HELENE 09/25/24 12 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) : 10.0 -49.5 to 33.0 0.72 16.8 MULTI-LAYER SHEAR (KT) : 15.9 46.9 to 6.8 0.77 9.2 HEAT CONTENT (KJ/CM2) : 61.2 0.0 to 155.1 0.39 3.8 STD DEV OF IR BR TEMP : 5.3 36.6 to 2.8 0.93 8.5 MAXIMUM WIND (KT) : 60.0 22.5 to 137.5 0.98 5.9 2nd PC OF IR BR TEMP : 0.1 2.9 to -3.0 0.47 2.4 BL DRY-AIR FLUX (W/M2) : 97.2 895.4 to -69.3 0.83 4.4 D200 (10**7s-1) : 110.8 -29.7 to 189.2 0.64 3.1 POT = MPI-VMAX (KT) : 112.1 27.0 to 143.0 0.73 2.2 %area of TPW <45 mm upshear : 3.1 109.2 to 0.0 0.97 -0.3 SHIPS Prob RI for 20kt/ 12hr RI threshold= 19% is 3.9 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 78% is 7.2 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 56% is 8.2 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 44% is 11.2 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 27% is 11.1 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 46% is 9.9 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 14% is 3.0 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: 19.0% 78.3% 56.0% 43.7% 26.5% 45.7% 14.2% 0.0% Logistic: 34.3% 64.7% 51.0% 35.0% 15.2% 10.7% 0.7% 0.0% Bayesian: 28.0% 10.0% 10.8% 21.0% 13.1% 1.3% 0.1% 0.0% Consensus: 27.1% 51.0% 39.3% 33.2% 18.3% 19.2% 5.0% 0.0% DTOPS: 21.0% 97.0% 88.0% 62.0% 28.0% 67.0% 0.0% 1.0% SDCON: 24.0% 74.0% 63.6% 47.6% 23.1% 43.1% 2.5% .5% ## ANNULAR HURRICANE INDEX (AHI) AL092024 HELENE 09/25/24 12 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 AL092024 HELENE 09/25/2024 12 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 0 6( 6) 21( 26) 29( 47) <-- PROB BASED ON INTENSITY ONLY PROB(%) 0 1( 1) 3( 4) 0( 4) <-- 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) 60 68 77 87 98 110 53 35 29 28 27 DIS DIS DIS DIS DIS DIS 18HR AGO 60 59 68 78 89 101 44 26 20 19 18 DIS DIS DIS DIS DIS DIS 12HR AGO 60 57 56 66 77 89 32 DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS 6HR AGO 60 54 51 50 61 73 16 DIS DIS DIS DIS 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