* GFS version * * ATLANTIC 2024 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * HELENE AL092024 09/26/24 06 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 79 84 86 85 79 67 52 37 22 N/A N/A N/A N/A N/A N/A N/A V (KT) LAND 75 79 84 86 62 38 30 28 27 27 N/A N/A N/A N/A N/A N/A N/A V (KT) LGEM 75 77 81 84 62 37 30 28 27 27 27 N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP TROP EXTP EXTP EXTP EXTP EXTP EXTP N/A N/A N/A N/A N/A N/A SHEAR (KT) 5 4 6 18 31 30 8 17 33 43 42 N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) 3 3 3 6 4 0 0 0 0 -5 0 N/A N/A N/A N/A N/A N/A SHEAR DIR 190 285 254 224 230 198 231 250 251 245 267 N/A N/A N/A N/A N/A N/A SST (C) 31.0 30.6 30.3 29.5 28.8 26.3 22.4 22.9 25.6 26.0 26.0 N/A N/A N/A N/A N/A N/A POT. INT. (KT) 173 174 175 165 153 118 86 89 109 109 109 N/A N/A N/A N/A N/A N/A 200 MB T (C) -50.1 -49.7 -48.8 -48.3 -47.7 -47.5 -48.7 -50.0 -49.9 -50.2 -50.0 N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 1.4 1.4 1.5 2.0 2.6 1.3 0.2 1.1 1.0 0.8 0.6 N/A N/A N/A N/A N/A N/A TH_E DEV (C) 8 7 8 5 3 1 0 1 0 2 0 N/A N/A N/A N/A N/A N/A 700-500 MB RH 72 70 64 57 54 51 49 48 48 45 41 N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 36 37 40 40 39 36 28 19 14 10 9 LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 99 121 157 166 155 187 173 145 131 104 40 N/A N/A N/A N/A N/A N/A 200 MB DIV 83 81 91 72 72 136 -1 14 -15 -4 -31 N/A N/A N/A N/A N/A N/A 700-850 TADV 13 31 40 50 66 65 -2 0 0 -2 2 N/A N/A N/A N/A N/A N/A LAND (KM) 228 329 257 72 -168 -553 -629 -618 -603 -541 -553 N/A N/A N/A N/A N/A N/A LAT (DEG N) 23.6 25.2 26.7 29.2 31.6 35.6 36.4 36.3 36.3 36.3 36.3 N/A N/A N/A N/A N/A N/A LONG(DEG W) 86.5 85.8 85.1 84.6 84.0 85.6 88.0 87.9 85.6 84.6 84.8 N/A N/A N/A N/A N/A N/A STM SPEED (KT) 13 17 21 25 22 15 5 5 7 2 1 N/A N/A N/A N/A N/A N/A HEAT CONTENT 59 63 34 24 6 5 5 5 5 5 5 N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT): 5/ 9 CX,CY: 1/ 9 T-12 MAX WIND: 75 PRESSURE OF STEERING LEVEL (MB): 651 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 7.7 (MEAN=14.5) % GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 98.0 (MEAN=65.0) PRELIM RI PROB (DV .GE. 35 KT IN 36 HR): 10.4 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 2. 4. 5. 5. 3. -2. -9. -14. -19. -24. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR MAG 0. 1. 0. -2. -5. -4. -2. -2. -3. -3. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR ADJ -0. -0. -1. -1. -2. -1. -1. -0. 0. 1. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR DIR -0. -0. 0. 0. 1. 2. 3. 4. 4. 5. 0. 0. 0. 0. 0. 0. PERSISTENCE -0. -1. -1. -1. -0. -0. -0. -0. -0. 0. 0. 0. 0. 0. 0. 0. 200/250 MB TEMP. -0. -1. -2. -3. -5. -6. -6. -6. -6. -6. 0. 0. 0. 0. 0. 0. THETA_E EXCESS -0. -0. -0. -1. -2. -3. -4. -5. -6. -6. 0. 0. 0. 0. 0. 0. 700-500 MB RH -0. -0. -1. -1. -1. -1. -1. -1. -0. 0. 0. 0. 0. 0. 0. 0. MODEL VTX TENDENCY 0. 2. 2. 2. -1. -11. -24. -33. -42. -46. 0. 0. 0. 0. 0. 0. 850 MB ENV VORTICITY 0. 1. 1. 2. 3. 4. 5. 5. 5. 5. 0. 0. 0. 0. 0. 0. 200 MB DIVERGENCE 0. 1. 1. 1. 2. 2. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 850-700 T ADVEC -0. 0. 1. 1. 3. 4. 4. 3. 3. 2. 0. 0. 0. 0. 0. 0. ZONAL STORM MOTION 0. 0. -0. -0. -0. -1. -1. -1. -1. -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. 1. 1. 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 0. 0. 0. 0. 0. 0. 0. -0. -0. 0. 0. 0. 0. 0. 0. 0. -------------------------------------------------------------------------------------------- TOTAL CHANGE 4. 9. 11. 10. 4. -8. -23. -38. -53. -62. 0. 0. 0. 0. 0. 0. CURRENT MAX WIND (KT): 75. LAT, LON: 23.6 86.5 ** 2024 ATLANTIC RI INDEX AL092024 HELENE 09/26/24 06 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 4.6 MULTI-LAYER SHEAR (KT) : 25.7 46.9 to 6.8 0.53 2.1 HEAT CONTENT (KJ/CM2) : 37.2 0.0 to 155.1 0.24 0.8 STD DEV OF IR BR TEMP : 7.7 36.6 to 2.8 0.85 2.6 MAXIMUM WIND (KT) : 75.0 22.5 to 137.5 0.81 1.6 2nd PC OF IR BR TEMP : 0.2 2.9 to -3.0 0.46 0.8 BL DRY-AIR FLUX (W/M2) : 286.2 895.4 to -69.3 0.63 1.1 D200 (10**7s-1) : 79.8 -29.7 to 189.2 0.50 0.8 POT = MPI-VMAX (KT) : 90.0 27.0 to 143.0 0.54 0.5 %area of TPW <45 mm upshear : 31.6 109.2 to 0.0 0.71 -0.1 SHIPS Prob RI for 20kt/ 12hr RI threshold= 11% is 2.2 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 29% is 2.6 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 15% is 2.2 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 9% is 2.4 times climatological mean ( 3.9%) SHIPS Prob RI for 40kt/ 24hr RI threshold= 7% is 3.1 times climatological mean ( 2.4%) SHIPS Prob RI for 45kt/ 36hr RI threshold= 11% is 2.4 times climatological mean ( 4.6%) SHIPS Prob RI for 55kt/ 48hr RI threshold= 0% is 0.0 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: 10.7% 28.8% 14.8% 9.4% 7.3% 10.9% 0.0% 0.0% Logistic: 9.6% 6.8% 6.9% 3.7% 0.5% 0.3% 0.0% 0.0% Bayesian: 3.8% 2.2% 0.8% 2.2% 0.3% 0.0% 0.0% 0.0% Consensus: 8.0% 12.6% 7.5% 5.1% 2.7% 3.7% 0.0% 0.0% DTOPS: 43.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 1.0% SDCON: 25.5% 6.3% 3.7% 2.5% 1.3% 1.8% 0% .5% ## ANNULAR HURRICANE INDEX (AHI) AL092024 HELENE 09/26/24 06 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 09/26/2024 06 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 5 9( 14) 0( 14) 0( 14) <-- PROB BASED ON INTENSITY ONLY PROB(%) 3 5( 8) 0( 8) 0( 8) <-- 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 79 84 86 62 38 30 28 27 27 DIS DIS DIS DIS DIS DIS DIS 18HR AGO 75 74 79 81 57 33 25 23 22 22 DIS DIS DIS DIS DIS DIS DIS 12HR AGO 75 72 71 73 49 25 17 15 DIS DIS DIS DIS DIS DIS DIS DIS DIS 6HR AGO 75 69 66 65 41 17 DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS DIS NOW CURRENT INTENSITY < 83 KT IN 6HR INTENSITY IN 6HR < 83 KT IN 12HR 75 79 84 75 69 65 57 55 54 54 27 27 27 27 27 27 27