* GFS version * * ATLANTIC 2024 SHIPS INTENSITY FORECAST * * IR SAT DATA AVAILABLE, OHC AVAILABLE * * HELENE AL092024 09/26/24 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 105 111 110 103 92 72 51 38 20 N/A N/A N/A N/A N/A N/A N/A N/A V (KT) LAND 105 111 76 55 43 32 28 27 27 N/A N/A N/A N/A N/A N/A N/A N/A V (KT) LGEM 105 113 80 56 43 31 28 27 27 N/A N/A N/A N/A N/A N/A N/A N/A Storm Type TROP TROP TROP TROP EXTP EXTP EXTP EXTP EXTP N/A N/A N/A N/A N/A N/A N/A N/A SHEAR (KT) 8 20 30 33 34 18 17 29 35 N/A N/A N/A N/A N/A N/A N/A N/A SHEAR ADJ (KT) 2 5 5 6 5 1 1 -6 -8 N/A N/A N/A N/A N/A N/A N/A N/A SHEAR DIR 236 214 230 224 206 207 225 240 236 N/A N/A N/A N/A N/A N/A N/A N/A SST (C) 30.0 29.4 28.8 27.8 26.9 20.9 20.9 21.5 23.2 N/A N/A N/A N/A N/A N/A N/A N/A POT. INT. (KT) 174 164 153 138 125 79 77 80 90 N/A N/A N/A N/A N/A N/A N/A N/A 200 MB T (C) -49.1 -48.6 -48.0 -47.9 -47.8 -48.5 -49.3 -49.8 -50.6 N/A N/A N/A N/A N/A N/A N/A N/A 200 MB VXT (C) 1.1 1.7 2.3 2.7 1.9 0.4 1.3 1.1 0.3 N/A N/A N/A N/A N/A N/A N/A N/A TH_E DEV (C) 8 6 3 1 1 0 1 0 2 N/A N/A N/A N/A N/A N/A N/A N/A 700-500 MB RH 64 56 57 60 54 47 48 47 47 N/A N/A N/A N/A N/A N/A N/A N/A MODEL VTX (KT) 39 39 38 36 33 29 20 17 11 LOST LOST LOST LOST LOST LOST LOST LOST 850 MB ENV VOR 153 160 158 176 171 170 144 121 91 N/A N/A N/A N/A N/A N/A N/A N/A 200 MB DIV 89 86 98 110 145 37 18 0 10 N/A N/A N/A N/A N/A N/A N/A N/A 700-850 TADV 38 32 52 43 68 -9 3 0 0 N/A N/A N/A N/A N/A N/A N/A N/A LAND (KM) 239 75 -195 -370 -561 -679 -666 -642 -653 N/A N/A N/A N/A N/A N/A N/A N/A LAT (DEG N) 26.7 29.3 31.8 33.9 36.0 36.8 36.7 36.5 36.5 N/A N/A N/A N/A N/A N/A N/A N/A LONG(DEG W) 84.9 84.3 83.7 84.5 85.3 87.1 87.2 87.4 86.6 N/A N/A N/A N/A N/A N/A N/A N/A STM SPEED (KT) 23 26 23 22 14 4 1 1 3 N/A N/A N/A N/A N/A N/A N/A N/A HEAT CONTENT 33 24 5 5 5 5 5 5 5 N/A N/A N/A N/A N/A N/A N/A N/A FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT): 25/ 20 CX,CY: 8/ 18 T-12 MAX WIND: 75 PRESSURE OF STEERING LEVEL (MB): 516 (MEAN=620) GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 6.7 (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): 0.1 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. 8. 9. 10. 0. 0. 0. 0. 0. 0. 0. 0. SST POTENTIAL 1. 3. 3. 1. -7. -19. -31. -42. 0. 0. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR MAG -2. -6. -11. -16. -20. -18. -16. -15. 0. 0. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR ADJ -0. -0. -1. -1. -1. -1. 0. 2. 0. 0. 0. 0. 0. 0. 0. 0. VERTICAL SHEAR DIR 0. 0. 0. 1. 2. 3. 4. 5. 0. 0. 0. 0. 0. 0. 0. 0. PERSISTENCE 5. 6. 5. 3. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 0. 200/250 MB TEMP. -1. -1. -2. -3. -5. -6. -6. -6. 0. 0. 0. 0. 0. 0. 0. 0. THETA_E EXCESS -0. -0. -1. -1. -3. -4. -5. -6. 0. 0. 0. 0. 0. 0. 0. 0. 700-500 MB RH -0. -0. -0. -0. -0. 0. 0. 1. 0. 0. 0. 0. 0. 0. 0. 0. MODEL VTX TENDENCY -0. -1. -2. -5. -10. -23. -30. -41. 0. 0. 0. 0. 0. 0. 0. 0. 850 MB ENV VORTICITY 1. 1. 2. 2. 3. 4. 5. 5. 0. 0. 0. 0. 0. 0. 0. 0. 200 MB DIVERGENCE 0. 1. 1. 2. 2. 1. 1. 1. 0. 0. 0. 0. 0. 0. 0. 0. 850-700 T ADVEC -0. 0. 1. 1. 2. 3. 3. 3. 0. 0. 0. 0. 0. 0. 0. 0. ZONAL STORM MOTION 0. 0. -0. -0. -1. -1. -1. -1. 0. 0. 0. 0. 0. 0. 0. 0. STEERING LEVEL PRES 0. 0. 0. 1. 1. 1. 0. 1. 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. 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 -0. -1. -2. -3. -4. -4. -3. -2. 0. 0. 0. 0. 0. 0. 0. 0. -------------------------------------------------------------------------------------------- TOTAL CHANGE 6. 5. -2. -13. -33. -54. -67. -85. 0. 0. 0. 0. 0. 0. 0. 0. CURRENT MAX WIND (KT): 105. LAT, LON: 26.7 84.9 ** 2024 ATLANTIC RI INDEX AL092024 HELENE 09/26/24 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) : 30.0 -49.5 to 33.0 0.96 6.9 MULTI-LAYER SHEAR (KT) : 38.6 46.9 to 6.8 0.21 0.8 HEAT CONTENT (KJ/CM2) : 14.4 0.0 to 155.1 0.09 0.3 STD DEV OF IR BR TEMP : 6.7 36.6 to 2.8 0.88 2.5 MAXIMUM WIND (KT) : 105.0 22.5 to 137.5 0.42 0.8 2nd PC OF IR BR TEMP : -0.1 2.9 to -3.0 0.51 0.8 BL DRY-AIR FLUX (W/M2) : 450.8 895.4 to -69.3 0.46 0.8 D200 (10**7s-1) : 105.6 -29.7 to 189.2 0.62 0.9 POT = MPI-VMAX (KT) : 37.0 27.0 to 143.0 0.09 0.1 %area of TPW <45 mm upshear : 52.3 109.2 to 0.0 0.52 -0.0 SHIPS Prob RI for 20kt/ 12hr RI threshold= 25% is 5.0 times climatological mean ( 4.9%) SHIPS Prob RI for 25kt/ 24hr RI threshold= 17% is 1.6 times climatological mean (10.9%) SHIPS Prob RI for 30kt/ 24hr RI threshold= 14% is 2.0 times climatological mean ( 6.8%) SHIPS Prob RI for 35kt/ 24hr RI threshold= 9% is 2.2 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= 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: 24.5% 17.3% 13.6% 8.7% 0.0% 0.0% 0.0% 0.0% Logistic: 29.5% 5.2% 7.3% 5.2% 0.3% 0.3% 0.0% 0.0% Bayesian: 17.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% Consensus: 23.7% 7.5% 7.0% 4.6% 0.1% 0.1% 0.0% 0.0% DTOPS: 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 1.0% SDCON: 11.8% 3.7% 3.5% 2.3% 0% 0% 0% .5% ## ANNULAR HURRICANE INDEX (AHI) AL092024 HELENE 09/26/24 18 UTC ## ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=4 NFAIL=3 ## ## 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 18 UTC ** TIME(HR) 0-12 12-24(0-24) 24-36(0-36) 36-48(0-48) CLIMO(%) 27 0( 27) 0( 27) 0( 27) <-- PROB BASED ON INTENSITY ONLY PROB(%) 38 0( 38) 0( 38) 0( 38) <-- 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) 105 111 76 55 43 32 28 27 27 DIS DIS DIS DIS DIS DIS DIS DIS 18HR AGO 105 104 69 48 36 25 21 20 20 DIS DIS DIS DIS DIS DIS DIS DIS 12HR AGO 105 102 101 80 68 57 53 52 52 25 25 25 25 25 25 25 25 6HR AGO 105 99 96 95 83 72 68 67 67 40 40 40 40 40 40 40 40 NOW 105 96 90 87 86 75 71 70 70 43 43 43 43 43 43 43 43 IN 6HR 105 111 102 96 93 89 85 84 84 57 57 57 57 57 57 57 57 IN 12HR INTENSITY IN 12HR < 83 KT