EPAC: EIGHT-E - Post-Tropical

[cycloneye]

An extensive area of showers and thunderstorms well southwest of the
southern tip of the Baja California peninsula is associated with
an area of low pressure along a tropical wave. Environmental
conditions are conducive for development, and a tropical depression
is likely to form by the middle of next week while the low moves
westward to west-northwestward at around 15 mph.
* Formation chance through 48 hours...low...near 0 percent
* Formation chance through 5 days...high...70 percent

[Yellow Evan]

Something is clearly off.

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST EP902015 07/25/15 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 25 28 31 36 40 50 59 65 70 71 73 74 74
V (KT) LAND 25 28 31 36 40 50 59 65 70 71 73 74 74
V (KT) LGE mod 25 27 29 32 34 41 50 60 69 77 82 85 87
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 7 6 7 8 10 15 19 23 24 25 20 19 20
SHEAR ADJ (KT) 6 5 2 0 -1 -2 -1 -2 -2 0 -1 -1 -2
SHEAR DIR 319 355 39 37 39 60 47 52 59 64 56 50 22
SST (C) 28.8 28.7 28.8 28.8 28.8 28.9 29.1 29.2 28.9 28.7 28.6 28.4 28.0
POT. INT. (KT) 154 153 154 154 153 153 155 156 152 150 149 147 143
200 MB T (C) -52.5 -52.4 -52.0 -52.3 -52.6 -52.4 -53.2 -52.6 -52.8 -52.7 -52.9 -52.8 -53.1
TH_E DEV (C) 6 6 6 6 6 6 6 7 7 8 7 8 8
700-500 MB RH 79 79 81 81 80 78 78 75 74 70 71 68 66
MODEL VTX (KT) 0 LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST
850 MB ENV VOR 11 15 18 23 26 29 34 27 16 24 36 33 16
200 MB DIV 51 39 56 68 69 68 54 37 15 23 56 83 55
700-850 TADV -3 -1 0 0 0 -1 -1 0 0 0 0 0 -1
LAND (KM) 2001 2095 2196 2287 2367 2487 2589 2670 2589 2465 2342 2200 2030
LAT (DEG N) 8.2 8.2 8.1 8.1 8.1 8.4 8.8 9.4 10.0 10.5 11.0 11.7 12.8
LONG(DEG W) 120.8 122.2 123.6 124.8 126.1 128.2 130.0 131.6 132.8 133.8 134.8 135.9 137.1
STM SPEED (KT) 15 14 13 12 12 10 9 8 6 6 6 7 8
HEAT CONTENT 18 25 40 45 40 18 15 14 15 17 20 31 32

FORECAST TRACK FROM BAMM INITIAL HEADING/SPEED (DEG/KT):275/ 16 CX,CY: -15/ 1
T-12 MAX WIND: 20 PRESSURE OF STEERING LEVEL (MB): 658 (MEAN=581)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 14.6 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 85.0 (MEAN=65.0)

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 0. 1. 1. 1. 0. 0. -1. -1. -2. -2.
SST POTENTIAL 0. 0. 1. 3. 8. 15. 22. 28. 31. 33. 35. 36.
VERTICAL SHEAR MAG 1. 2. 3. 3. 3. 3. 2. 0. -1. 0. 0. 0.
VERTICAL SHEAR ADJ 0. -1. -1. -1. -1. 0. 0. 0. 0. 0. 1. 1.
VERTICAL SHEAR DIR 0. 0. 1. 2. 4. 7. 10. 12. 14. 16. 16. 15.
PERSISTENCE 1. 1. 2. 2. 2. 2. 2. 1. 1. 1. 1. 0.
200/250 MB TEMP. 0. -1. -2. -2. -4. -6. -8. -9. -10. -10. -10. -10.
THETA_E EXCESS 0. 0. -1. -1. -2. -2. -3. -3. -3. -3. -4. -4.
700-500 MB RH 0. 1. 1. 1. 2. 3. 4. 5. 5. 5. 6. 6.
MODEL VTX TENDENCY 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 1. 1.
850 MB ENV VORTICITY 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
200 MB DIVERGENCE 0. 0. 1. 1. 2. 2. 1. 1. 0. 0. -1. -1.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
ZONAL STORM MOTION 0. 1. 2. 2. 4. 5. 6. 6. 5. 5. 5. 5.
STEERING LEVEL PRES 0. 0. 0. 0. 1. 1. 1. 2. 2. 2. 2. 2.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
GOES PREDICTORS 1. 2. 3. 3. 4. 3. 2. 1. 0. 0. -1. -1.
OCEAN HEAT CONTENT 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. 0.
----------------------------------------------------------
TOTAL CHANGE 3. 6. 11. 15. 25. 34. 40. 45. 46. 48. 49. 49.

** 2013 E. Pacific RI INDEX EP902015 INVEST 07/25/15 12 UTC **
( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)

12 HR PERSISTENCE (KT): 5.0 Range:-22.0 to 38.5 Scaled/Wgted Val: 0.4/ 1.0
850-200 MB SHEAR (KT) : 7.7 Range: 18.7 to 1.4 Scaled/Wgted Val: 0.6/ 0.9
POT = MPI-VMAX (KT) : 128.6 Range: 40.3 to 141.7 Scaled/Wgted Val: 0.9/ 0.9
STD DEV OF IR BR TEMP : 14.6 Range: 38.9 to 2.4 Scaled/Wgted Val: 0.7/ 0.7
Heat content (KJ/cm2) : 33.6 Range: 3.6 to 75.9 Scaled/Wgted Val: 0.4/ 0.4
D200 (10**7s-1) : 56.6 Range:-11.0 to 135.3 Scaled/Wgted Val: 0.5/ 0.3
% area w/pixels <-30 C: 73.0 Range: 41.4 to 100.0 Scaled/Wgted Val: 0.5/ 0.3
850-700 MB REL HUM (%): 80.4 Range: 57.6 to 96.8 Scaled/Wgted Val: 0.6/ -0.1

Prob of RI for 25 kt RI threshold= 50% is 3.8 times the sample mean(13.1%)
Prob of RI for 30 kt RI threshold= 29% is 3.4 times the sample mean( 8.7%)
Prob of RI for 35 kt RI threshold= 21% is 3.5 times the sample mean( 6.0%)
Prob of RI for 40 kt RI threshold= 15% is 3.5 times the sample mean( 4.3%) * EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST EP902015 07/25/15 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 25 28 31 36 40 50 59 65 70 71 73 74 74
V (KT) LAND 25 28 31 36 40 50 59 65 70 71 73 74 74
V (KT) LGE mod 25 27 29 32 34 41 50 60 69 77 82 85 87
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 7 6 7 8 10 15 19 23 24 25 20 19 20
SHEAR ADJ (KT) 6 5 2 0 -1 -2 -1 -2 -2 0 -1 -1 -2
SHEAR DIR 319 355 39 37 39 60 47 52 59 64 56 50 22
SST (C) 28.8 28.7 28.8 28.8 28.8 28.9 29.1 29.2 28.9 28.7 28.6 28.4 28.0
POT. INT. (KT) 154 153 154 154 153 153 155 156 152 150 149 147 143
200 MB T (C) -52.5 -52.4 -52.0 -52.3 -52.6 -52.4 -53.2 -52.6 -52.8 -52.7 -52.9 -52.8 -53.1
TH_E DEV (C) 6 6 6 6 6 6 6 7 7 8 7 8 8
700-500 MB RH 79 79 81 81 80 78 78 75 74 70 71 68 66
MODEL VTX (KT) 0 LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST LOST
850 MB ENV VOR 11 15 18 23 26 29 34 27 16 24 36 33 16
200 MB DIV 51 39 56 68 69 68 54 37 15 23 56 83 55
700-850 TADV -3 -1 0 0 0 -1 -1 0 0 0 0 0 -1
LAND (KM) 2001 2095 2196 2287 2367 2487 2589 2670 2589 2465 2342 2200 2030
LAT (DEG N) 8.2 8.2 8.1 8.1 8.1 8.4 8.8 9.4 10.0 10.5 11.0 11.7 12.8
LONG(DEG W) 120.8 122.2 123.6 124.8 126.1 128.2 130.0 131.6 132.8 133.8 134.8 135.9 137.1
STM SPEED (KT) 15 14 13 12 12 10 9 8 6 6 6 7 8
HEAT CONTENT 18 25 40 45 40 18 15 14 15 17 20 31 32

FORECAST TRACK FROM BAMM INITIAL HEADING/SPEED (DEG/KT):275/ 16 CX,CY: -15/ 1
T-12 MAX WIND: 20 PRESSURE OF STEERING LEVEL (MB): 658 (MEAN=581)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 14.6 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 85.0 (MEAN=65.0)

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 0. 1. 1. 1. 0. 0. -1. -1. -2. -2.
SST POTENTIAL 0. 0. 1. 3. 8. 15. 22. 28. 31. 33. 35. 36.
VERTICAL SHEAR MAG 1. 2. 3. 3. 3. 3. 2. 0. -1. 0. 0. 0.
VERTICAL SHEAR ADJ 0. -1. -1. -1. -1. 0. 0. 0. 0. 0. 1. 1.
VERTICAL SHEAR DIR 0. 0. 1. 2. 4. 7. 10. 12. 14. 16. 16. 15.
PERSISTENCE 1. 1. 2. 2. 2. 2. 2. 1. 1. 1. 1. 0.
200/250 MB TEMP. 0. -1. -2. -2. -4. -6. -8. -9. -10. -10. -10. -10.
THETA_E EXCESS 0. 0. -1. -1. -2. -2. -3. -3. -3. -3. -4. -4.
700-500 MB RH 0. 1. 1. 1. 2. 3. 4. 5. 5. 5. 6. 6.
MODEL VTX TENDENCY 0. 0. 0. 0. 0. 0. 0. 0. 1. 1. 1. 1.
850 MB ENV VORTICITY 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
200 MB DIVERGENCE 0. 0. 1. 1. 2. 2. 1. 1. 0. 0. -1. -1.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
ZONAL STORM MOTION 0. 1. 2. 2. 4. 5. 6. 6. 5. 5. 5. 5.
STEERING LEVEL PRES 0. 0. 0. 0. 1. 1. 1. 2. 2. 2. 2. 2.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
GOES PREDICTORS 1. 2. 3. 3. 4. 3. 2. 1. 0. 0. -1. -1.
OCEAN HEAT CONTENT 0. 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. 0.
----------------------------------------------------------
TOTAL CHANGE 3. 6. 11. 15. 25. 34. 40. 45. 46. 48. 49. 49.

** 2013 E. Pacific RI INDEX EP902015 INVEST 07/25/15 12 UTC **
( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)

12 HR PERSISTENCE (KT): 5.0 Range:-22.0 to 38.5 Scaled/Wgted Val: 0.4/ 1.0
850-200 MB SHEAR (KT) : 7.7 Range: 18.7 to 1.4 Scaled/Wgted Val: 0.6/ 0.9
POT = MPI-VMAX (KT) : 128.6 Range: 40.3 to 141.7 Scaled/Wgted Val: 0.9/ 0.9
STD DEV OF IR BR TEMP : 14.6 Range: 38.9 to 2.4 Scaled/Wgted Val: 0.7/ 0.7
Heat content (KJ/cm2) : 33.6 Range: 3.6 to 75.9 Scaled/Wgted Val: 0.4/ 0.4
D200 (10**7s-1) : 56.6 Range:-11.0 to 135.3 Scaled/Wgted Val: 0.5/ 0.3
% area w/pixels <-30 C: 73.0 Range: 41.4 to 100.0 Scaled/Wgted Val: 0.5/ 0.3
850-700 MB REL HUM (%): 80.4 Range: 57.6 to 96.8 Scaled/Wgted Val: 0.6/ -0.1

Prob of RI for 25 kt RI threshold= 50% is 3.8 times the sample mean(13.1%)
Prob of RI for 30 kt RI threshold= 29% is 3.4 times the sample mean( 8.7%)
Prob of RI for 35 kt RI threshold= 21% is 3.5 times the sample mean( 6.0%)
Prob of RI for 40 kt RI threshold= 15% is 3.5 times the sample mean( 4.3%)

[Yellow Evan]

A large but disorganized area of showers and thunderstorms centered
about 1000 miles southwest of the southern tip of the Baja
California peninsula is associated with an area of low pressure
along a tropical wave. Environmental conditions are conducive for
development, and a tropical depression is likely to form by the
middle of next week while the low moves west-northwestward at around
15 mph.
* Formation chance through 48 hours...low...near 0 percent
* Formation chance through 5 days...high...70 percent

[Yellow Evan]

0z ECMWF made this a solid hurricane.

[Yellow Evan]

An area of low pressure centered about 1050 miles southwest of
the southern tip of the Baja California peninsula is producing a
large area of cloudiness and showers. Environmental conditions are
conducive for development, and a tropical depression is likely to
form during the next few days while the low moves west-northwestward
at around 15 mph.
* Formation chance through 48 hours...low...20 percent
* Formation chance through 5 days...high...90 percent

[Yellow Evan]

Track too far north bringing it closer to the Great Hawaiian Shear.

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST EP902015 07/26/15 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 30 34 38 43 47 55 61 65 67 65 62 58 56
V (KT) LAND 30 34 38 43 47 55 61 65 67 65 62 58 56
V (KT) LGE mod 30 33 36 39 42 48 52 56 59 60 58 53 48
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 5 8 8 7 10 11 11 9 9 9 18 21 26
SHEAR ADJ (KT) 1 -1 -4 -4 -3 -2 -5 -3 -4 -2 -1 2 3
SHEAR DIR 332 338 346 327 322 338 331 343 337 307 310 312 307
SST (C) 29.0 28.8 28.5 28.4 28.3 27.9 28.0 27.9 27.1 26.0 25.5 25.6 25.5
POT. INT. (KT) 156 155 151 150 149 144 145 144 136 125 119 120 119
200 MB T (C) -52.9 -52.8 -52.4 -52.4 -52.6 -52.4 -52.9 -52.8 -53.0 -52.8 -53.1 -52.9 -53.0
TH_E DEV (C) 8 8 9 8 8 8 8 8 8 8 7 6 5
700-500 MB RH 73 70 70 73 74 72 69 65 59 56 53 55 58
MODEL VTX (KT) 5 5 6 7 8 9 10 12 13 13 13 13 13
850 MB ENV VOR 0 -7 -7 -2 -4 -11 -3 7 20 35 18 1 -3
200 MB DIV 58 40 32 37 31 37 19 13 29 22 14 -9 -21
700-850 TADV 0 1 0 -1 -1 -1 0 2 1 2 4 8 12
LAND (KM) 1555 1593 1647 1681 1726 1828 1937 2052 2217 2035 1748 1467 1225
LAT (DEG N) 11.3 12.0 12.6 13.1 13.6 14.7 15.5 16.2 16.8 17.5 18.4 19.3 20.2
LONG(DEG W) 118.2 119.7 121.2 122.5 123.7 126.1 128.3 130.5 133.0 135.6 138.2 140.8 143.1
STM SPEED (KT) 14 16 15 13 13 12 11 12 12 13 13 13 11
HEAT CONTENT 51 34 21 14 14 24 17 19 11 5 0 1 1

FORECAST TRACK FROM BAMM INITIAL HEADING/SPEED (DEG/KT):295/ 12 CX,CY: -10/ 5
T-12 MAX WIND: 25 PRESSURE OF STEERING LEVEL (MB): 603 (MEAN=581)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 10.5 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 92.0 (MEAN=65.0)

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 0. 1. 1. 1. 0. 0. -1. -1. -2. -2.
SST POTENTIAL 0. 1. 2. 3. 8. 14. 19. 23. 25. 25. 26. 25.
VERTICAL SHEAR MAG 1. 2. 3. 3. 4. 5. 5. 5. 5. 4. 3. 1.
VERTICAL SHEAR ADJ 0. 0. 1. 1. 1. 2. 2. 2. 2. 2. 2. 2.
VERTICAL SHEAR DIR 0. 0. -1. -1. -2. -3. -3. -4. -4. -5. -5. -5.
PERSISTENCE 1. 1. 2. 2. 2. 2. 2. 1. 1. 1. 1. 0.
200/250 MB TEMP. 0. -1. -2. -2. -4. -6. -7. -9. -10. -10. -9. -9.
THETA_E EXCESS 0. 0. 0. 0. 0. 0. 0. -1. -1. -1. -2. -3.
700-500 MB RH 0. 0. 1. 1. 2. 2. 3. 3. 3. 3. 3. 3.
MODEL VTX TENDENCY 0. 1. 2. 3. 6. 8. 10. 12. 12. 12. 12. 13.
850 MB ENV VORTICITY 0. 0. 0. 0. -1. -1. -1. -1. -1. -1. -2. -2.
200 MB DIVERGENCE 0. 0. 0. 1. 1. 1. 0. 0. 0. 0. 0. 0.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1.
ZONAL STORM MOTION 0. 0. 1. 1. 1. 2. 2. 2. 2. 2. 2. 2.
STEERING LEVEL PRES 0. 0. 0. 0. 0. 0. 1. 1. 1. 1. 1. 1.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
GOES PREDICTORS 2. 3. 4. 4. 5. 4. 4. 3. 2. 1. 0. 0.
OCEAN HEAT CONTENT 0. 1. 1. 1. 1. 1. 1. 0. 0. 0. 0. 0.
----------------------------------------------------------
TOTAL CHANGE 4. 8. 13. 17. 25. 31. 35. 37. 35. 32. 28. 26.

** 2013 E. Pacific RI INDEX EP902015 INVEST 07/26/15 12 UTC **
( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)

12 HR PERSISTENCE (KT): 5.0 Range:-22.0 to 38.5 Scaled/Wgted Val: 0.4/ 1.0
850-200 MB SHEAR (KT) : 7.5 Range: 18.7 to 1.4 Scaled/Wgted Val: 0.6/ 0.9
POT = MPI-VMAX (KT) : 122.1 Range: 40.3 to 141.7 Scaled/Wgted Val: 0.8/ 0.9
STD DEV OF IR BR TEMP : 10.5 Range: 38.9 to 2.4 Scaled/Wgted Val: 0.8/ 0.8
Heat content (KJ/cm2) : 26.8 Range: 3.6 to 75.9 Scaled/Wgted Val: 0.3/ 0.3
D200 (10**7s-1) : 39.6 Range:-11.0 to 135.3 Scaled/Wgted Val: 0.3/ 0.3
% area w/pixels <-30 C: 83.0 Range: 41.4 to 100.0 Scaled/Wgted Val: 0.7/ 0.3
850-700 MB REL HUM (%): 75.8 Range: 57.6 to 96.8 Scaled/Wgted Val: 0.5/ -0.1

Prob of RI for 25 kt RI threshold= 49% is 3.7 times the sample mean(13.1%)
Prob of RI for 30 kt RI threshold= 29% is 3.4 times the sample mean( 8.7%)
Prob of RI for 35 kt RI threshold= 21% is 3.5 times the sample mean( 6.0%)
Prob of RI for 40 kt RI threshold= 16% is 3.6 times the sample mean( 4.3%)

## ANNULAR HURRICANE INDEX (AHI) EP902015 INVEST 07/26/15 12 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) ##

[Yellow Evan]

If we get lucky, this can become a minimal hurricane. It is located within the deep tropics and is in a low wind shear environment. ECMWF is bullish with this, and if it stays south, which the ECMWF/GFS and the statical guidance are torn over, the storm will be in a very favorable environment provided it remains apart from the ITCZ. If it goes north (and if the current NHC center fix is likely correct), this may be a very weak TS at best though its remnants if it goes north may give rain to Hawaii.

[Yellow Evan]

An area of low pressure located about 1000 miles southwest of
the southern tip of the Baja California peninsula continues to
produce disorganized showers and thunderstorms. Environmental
conditions are somewhat conducive for development, and a tropical
depression is likely to form by Wednesday while the low moves west-
northwestward at around 15 mph.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...high...90 percent

[Yellow Evan]

12z HWRF was very bullish, but 18z HWRF backed off likely due to the center moving a bit to the N (according to SAB, may be near 14N). Given the center forming to the north, expect a major decline in intensity at 0z round of global models.

[Yellow Evan]

0z GFS showers very little development. So does the UKMET. I'm not keen on this at all.

NHC bring it down. Thank goodness.

Shower activity associated with a low pressure system located about
1000 miles southwest of the southern tip of the Baja California
peninsula is limited and disorganized. Even though environmental
conditions are expected to be only somewhat conducive for
development, a tropical depression is still likely to form around
mid-week while the low moves west-northwestward at around 15 mph.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...high...70 percent

[Yellow Evan]

If anyone cares, convection has really increased after 12z. This might get classified somewhat soon, assuming there is a well-defined center. GFS hasn't initialized properly, but only calls for slight development. But if the convection falls apart, this won't. Models have backed off somewhat, with 0z ECMWF calling for a weak but long-lived TS (like Genevieve prior to the EI), HWRF calling for only a mid-grade TS after showing a MH 2 runs ago, and the GFDL no longer develops this really. Worth noting though that the TVCE consensus is quite far south, so once can assume the NOGAPS/UKMET keep this south still, which could allow for the storm to be over lower wind shear.

500 AM TWO:

A low pressure system located about 1050 miles southwest of the
southern tip of the Baja California peninsula continues to produce
a large area of cloudiness and showers. Environmental conditions are
expected to be somewhat conducive for a tropical depression to form
around mid-week while the low moves west-northwestward at 15 mph.
* Formation chance through 48 hours...medium...50 percent
* Formation chance through 5 days...high...70 percent

[cycloneye]

A well-defined low pressure system is located about 1100 miles
southwest of the southern tip of the Baja California peninsula.
Shower and thunderstorm activity has increased and become better
organized near the center of the low overnight and this morning.
If this development trend continues, a tropical depression could
form this afternoon or tonight while the low moves
west-northwestward at 15 mph.
* Formation chance through 48 hours...high...80 percent
* Formation chance through 5 days...high...80 percent

[Yellow Evan]

It's close, but I don't think it's there yet. I'd like to see some more banding and slightly better organization.


EP, 90, 2015072718, , BEST, 0, 156N, 1253W, 30, 1007, LO, 34, NEQ, 0, 0, 0, 0, 1011, 150, 60, 0, 0, E, 0, , 0, 0, INVEST, M, 0, , 0, 0, 0, 0, genesis-num, 012,

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* INVEST EP902015 07/27/15 18 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 30 30 31 32 35 38 39 38 34 29 26 25 27
V (KT) LAND 30 30 31 32 35 38 39 38 34 29 26 25 27
V (KT) LGE mod 30 30 30 31 31 32 32 32 29 27 24 21 21
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 19 17 13 15 16 13 19 16 21 20 20 17 19
SHEAR ADJ (KT) -3 -2 -2 -4 -4 -1 0 0 1 1 3 -2 -4
SHEAR DIR 325 339 340 333 341 329 341 340 327 316 314 286 276
SST (C) 28.2 28.0 28.1 28.2 28.1 27.6 26.9 26.4 26.3 26.4 26.5 26.8 27.0
POT. INT. (KT) 148 146 146 147 146 141 133 128 127 130 131 132 133
200 MB T (C) -52.7 -52.5 -52.5 -52.7 -52.7 -52.7 -53.0 -52.9 -53.2 -53.2 -53.3 -53.1 -53.3
TH_E DEV (C) 8 9 9 8 8 8 7 7 7 7 7 8 8
700-500 MB RH 65 66 64 64 61 58 54 52 48 46 42 40 42
MODEL VTX (KT) 6 7 8 8 8 9 8 7 6 5 4 2 LOST
850 MB ENV VOR -23 -21 -13 -10 -6 6 6 -1 -15 0 3 23 25
200 MB DIV -9 -7 -6 0 3 -5 0 -2 -21 -47 -50 -45 -8
700-850 TADV -3 -3 -2 -2 -2 0 0 3 6 2 7 1 8
LAND (KM) 1697 1790 1866 1938 2015 2191 2035 1811 1576 1280 889 615 416
LAT (DEG N) 15.6 xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x xx.x
LONG(DEG W) 125.3 xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x xxx.x
STM SPEED (KT) 15 14 13 12 12 12 11 10 12 15 15 11 9
HEAT CONTENT 17 12 13 18 21 16 6 4 1 4 6 15 15

FORECAST TRACK FROM OFPI INITIAL HEADING/SPEED (DEG/KT):290/ 15 CX,CY: -13/ 5
T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 657 (MEAN=581)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 28.0 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 45.0 (MEAN=65.0)

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 0. 1. 1. 1. 0. 0. -1. -1. -2. -2.
SST POTENTIAL 0. 1. 2. 3. 8. 13. 17. 20. 22. 23. 24. 24.
VERTICAL SHEAR MAG 0. 1. 1. 2. 2. 1. -1. -3. -5. -7. -7. -7.
VERTICAL SHEAR ADJ 0. 0. 1. 1. 2. 1. 1. 1. 1. 0. 1. 1.
VERTICAL SHEAR DIR 0. 0. -1. -1. -1. -2. -2. -3. -4. -4. -4. -5.
PERSISTENCE 0. 0. 0. -1. -1. -1. -1. -1. -1. -1. 0. 0.
200/250 MB TEMP. 0. 0. -1. -1. -3. -4. -5. -6. -7. -6. -6. -6.
THETA_E EXCESS 0. 0. 0. 0. 0. 0. -1. -1. -1. -2. -2. -2.
700-500 MB RH 0. 0. 0. 0. 1. 1. 1. 1. 0. 0. 0. 0.
MODEL VTX TENDENCY 0. 1. 1. 2. 3. 3. 2. 0. -2. -4. -5. -5.
850 MB ENV VORTICITY 0. 0. 0. 0. -1. -1. -1. -2. -2. -3. -3. -3.
200 MB DIVERGENCE 0. 0. -1. -1. -1. -1. -1. -1. 0. 0. 1. 2.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1.
ZONAL STORM MOTION 0. 1. 1. 2. 3. 4. 4. 4. 4. 4. 4. 3.
STEERING LEVEL PRES 0. 0. 0. 0. 1. 1. 1. 2. 2. 2. 2. 2.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
GOES PREDICTORS -1. -2. -3. -3. -4. -6. -6. -6. -6. -6. -6. -6.
OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -1. -1. -1. -1. -1. 0.
----------------------------------------------------------
TOTAL CHANGE 0. 1. 2. 5. 8. 9. 8. 4. -1. -4. -5. -3.

** 2013 E. Pacific RI INDEX EP902015 INVEST 07/27/15 18 UTC **
( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)

12 HR PERSISTENCE (KT): 0.0 Range:-22.0 to 38.5 Scaled/Wgted Val: 0.4/ 0.8
850-200 MB SHEAR (KT) : 16.0 Range: 18.7 to 1.4 Scaled/Wgted Val: 0.2/ 0.2
POT = MPI-VMAX (KT) : 116.7 Range: 40.3 to 141.7 Scaled/Wgted Val: 0.8/ 0.8
STD DEV OF IR BR TEMP : 28.0 Range: 38.9 to 2.4 Scaled/Wgted Val: 0.3/ 0.3
Heat content (KJ/cm2) : 16.2 Range: 3.6 to 75.9 Scaled/Wgted Val: 0.2/ 0.2
D200 (10**7s-1) : -3.8 Range:-11.0 to 135.3 Scaled/Wgted Val: 0.0/ 0.0
% area w/pixels <-30 C: 42.0 Range: 41.4 to 100.0 Scaled/Wgted Val: 0.0/ 0.0
850-700 MB REL HUM (%): 70.4 Range: 57.6 to 96.8 Scaled/Wgted Val: 0.3/ 0.0

Prob of RI for 25 kt RI threshold= 14% is 1.1 times the sample mean(13.1%)
Prob of RI for 30 kt RI threshold= 10% is 1.2 times the sample mean( 8.7%)
Prob of RI for 35 kt RI threshold= 6% is 1.0 times the sample mean( 6.0%)
Prob of RI for 40 kt RI threshold= 1% is 0.3 times the sample mean( 4.3%)

[cycloneye]

TROPICAL DEPRESSION EIGHT-E DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082015
200 PM PDT MON JUL 27 2015

The low pressure system located more than 1000 n mi west-southwest
of the Baja California peninsula has finally acquired enough
persistent deep convection near the center for it to be upgraded to
a tropical depression. An 1831 UTC ASCAT-B overpass indicated a
well-defined circulation center and inner-core wind field containing
several 30-31 kt surface wind vectors at a distance of 35-40 nmi to
the northeast and southeast of the center. Although the depression
is a sheared tropical cyclone, a T2.0/30 kt Dvorak satellite
classification from TAFB also justifies upgrading the low to a
tropical depression at this time.

The initial motion estimate is 290/14 kt, which is based primarily
on microwave and ASCAT satellite fixes. The NHC model guidance is
in good agreement on the tropical cyclone moving toward the
west-northwest at 12-14 kt for the next 72 hours or so due to a
strong deep-layer ridge locate to its north. After that, however,
the guidance diverges significantly with the ECMWF model taking a
very weak cyclone or trough west-southwestward, the GFS and HWRF
models moving the system westward, while the GFS-ensemble mean and
the remainder of the models keep the depression on a slower
west-northwestward track. The NHC official forecast track basically
lies down the middle of the guidance suite throughout the forecast
period and is close to the consensus model TVCE.

The cyclone is not expected to intensify much due to persistent
moderate northwesterly vertical wind shear and the cyclone moving
over marginal sea-surface temperatures after 72 hours. There will
also likely be occasional intrusions of drier and more stable air,
which lies just to the north of the forecast track, into the
cyclone. However, the well-established southerly low-level inflow
of unstable air should help to maintain enough convection to keep
this system as a tropical cyclone throughout the forecast period.
The NHC intensity forecast is similar to the ICON consensus model.

FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 15.6N 126.1W 30 KT 35 MPH
12H 28/0600Z 16.1N 128.1W 30 KT 35 MPH
24H 28/1800Z 16.6N 130.4W 35 KT 40 MPH
36H 29/0600Z 17.0N 132.6W 35 KT 40 MPH
48H 29/1800Z 17.3N 134.6W 35 KT 40 MPH
72H 30/1800Z 17.9N 139.8W 35 KT 40 MPH
96H 31/1800Z 18.2N 145.9W 35 KT 40 MPH
120H 01/1800Z 18.4N 151.3W 30 KT 35 MPH

$$
Forecaster Stewart

[Yellow Evan]

Wow, they pulled the trigger. And since it's become more organized, I agree with it.

[Kingarabian]

Surprised it made it.

[Kingarabian]

[Yellow Evan]

I thought the NHC TWO numbers were a tad too high. But these kind of low latitudes storms usually make it. Typical for this time of year, not a lot big quality storms.

It doesn't look too great by any means, but given it's expected duration, it'll likely become a TS at some point. If the storm lasts as long as the ECMWf, who knows, maybe it'll blossom. In a few days, this will have a CCKW going for it.

[Yellow Evan]

Seems to have rapidly become exposed. 30 knots is generous.

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* EIGHT EP082015 07/28/15 00 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 30 30 31 32 34 37 37 36 34 30 26 25 26
V (KT) LAND 30 30 31 32 34 37 37 36 34 30 26 25 26
V (KT) LGE mod 30 30 30 31 31 32 32 30 29 27 24 22 21
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 17 13 14 16 14 13 12 10 13 21 16 17 18
SHEAR ADJ (KT) -3 -3 -4 -4 -3 -1 0 3 1 3 0 0 -4
SHEAR DIR 333 338 334 341 347 342 352 324 302 309 301 282 262
SST (C) 28.1 28.0 28.1 28.2 28.0 27.6 27.0 26.4 26.4 26.5 26.7 27.0 27.1
POT. INT. (KT) 146 145 146 147 145 140 134 129 129 130 132 135 135
200 MB T (C) -52.5 -52.4 -52.5 -52.6 -52.5 -52.7 -52.7 -53.0 -53.0 -53.1 -52.9 -52.9 -53.0
TH_E DEV (C) 9 9 8 8 8 8 8 7 7 7 8 7 8
700-500 MB RH 64 63 62 60 59 57 54 53 50 48 47 48 47
MODEL VTX (KT) 8 9 9 9 10 9 8 7 6 5 4 2 LOST
850 MB ENV VOR -20 -14 -11 -5 -6 -4 -15 -16 -2 4 9 42 56
200 MB DIV -12 -12 -16 -2 -4 5 -8 -5 -5 -36 -24 -20 4
700-850 TADV -3 -3 -4 -3 -1 0 2 5 4 7 7 7 6
LAND (KM) 1777 1837 1903 1978 2057 2208 2077 1799 1472 1144 853 562 314
LAT (DEG N) 15.8 16.1 16.4 16.6 16.8 17.2 17.5 17.8 18.0 18.2 18.2 18.3 18.5
LONG(DEG W) 126.4 127.6 128.8 130.0 131.1 133.2 135.2 137.8 140.9 144.0 146.8 149.6 152.0
STM SPEED (KT) 13 12 12 11 11 10 11 14 15 14 13 12 11
HEAT CONTENT 14 12 17 19 22 15 5 4 1 7 8 16 15

FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):290/ 13 CX,CY: -11/ 4
T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 653 (MEAN=581)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 28.1 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 47.0 (MEAN=65.0)

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 0. 1. 1. 1. 0. 0. -1. -1. -2. -2.
SST POTENTIAL 0. 1. 2. 4. 8. 13. 17. 20. 22. 23. 24. 24.
VERTICAL SHEAR MAG 1. 1. 2. 2. 2. 2. 2. 1. -1. -2. -2. -3.
VERTICAL SHEAR ADJ 0. 1. 1. 1. 2. 2. 1. 1. 0. 0. 1. 1.
VERTICAL SHEAR DIR 0. 0. -1. -1. -1. -2. -2. -3. -4. -4. -5. -6.
PERSISTENCE 0. 0. 0. -1. -1. -1. -1. -1. -1. -1. 0. 0.
200/250 MB TEMP. 0. 0. -1. -1. -3. -4. -5. -6. -7. -7. -7. -6.
THETA_E EXCESS 0. 0. 0. 0. 0. 0. -1. -1. -1. -2. -2. -2.
700-500 MB RH 0. 0. 0. 0. 0. 1. 1. 0. 0. 0. 0. 0.
MODEL VTX TENDENCY 0. 0. 1. 2. 2. 1. -1. -2. -4. -6. -8. -8.
850 MB ENV VORTICITY 0. 0. 0. 0. -1. -1. -2. -2. -2. -3. -3. -2.
200 MB DIVERGENCE 0. -1. -1. -1. -1. -1. -1. -1. 0. 0. 1. 1.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 1.
ZONAL STORM MOTION 0. 1. 1. 1. 2. 3. 3. 3. 3. 3. 2. 2.
STEERING LEVEL PRES 0. 0. 0. 0. 0. 1. 1. 2. 2. 2. 2. 2.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
GOES PREDICTORS -1. -2. -3. -3. -4. -5. -6. -6. -6. -5. -5. -5.
OCEAN HEAT CONTENT 0. 0. 0. 0. 0. 0. -1. -1. -1. -1. -1. 0.
----------------------------------------------------------
TOTAL CHANGE 0. 1. 2. 4. 7. 7. 6. 4. 0. -4. -5. -4.

** 2013 E. Pacific RI INDEX EP082015 EIGHT 07/28/15 00 UTC **
( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)

12 HR PERSISTENCE (KT): 0.0 Range:-22.0 to 38.5 Scaled/Wgted Val: 0.4/ 0.8
850-200 MB SHEAR (KT) : 14.7 Range: 18.7 to 1.4 Scaled/Wgted Val: 0.2/ 0.3
POT = MPI-VMAX (KT) : 115.8 Range: 40.3 to 141.7 Scaled/Wgted Val: 0.7/ 0.8
STD DEV OF IR BR TEMP : 28.1 Range: 38.9 to 2.4 Scaled/Wgted Val: 0.3/ 0.3
Heat content (KJ/cm2) : 16.8 Range: 3.6 to 75.9 Scaled/Wgted Val: 0.2/ 0.2
D200 (10**7s-1) : -9.2 Range:-11.0 to 135.3 Scaled/Wgted Val: 0.0/ 0.0
% area w/pixels <-30 C: 40.0 Range: 41.4 to 100.0 Scaled/Wgted Val: 0.0/ 0.0
850-700 MB REL HUM (%): 68.6 Range: 57.6 to 96.8 Scaled/Wgted Val: 0.3/ 0.0

Prob of RI for 25 kt RI threshold= 14% is 1.1 times the sample mean(13.1%)
Prob of RI for 30 kt RI threshold= 3% is 0.3 times the sample mean( 8.7%)
Prob of RI for 35 kt RI threshold= 2% is 0.3 times the sample mean( 6.0%)
Prob of RI for 40 kt RI threshold= 1% is 0.3 times the sample mean( 4.3%)

[cycloneye]

TROPICAL DEPRESSION EIGHT-E DISCUSSION NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082015
800 PM PDT MON JUL 27 2015

The depression has become somewhat less organized since the last
advisory. The center has become exposed to the northwest of an
amorphous but persistent mass of deep convection. According to the
UW-CIMSS shear analyses, the cyclone's appearance is a result of
northwesterly shear of around 20 kt associated with an upper-level
trough located to its northeast. Last-light visible satellite
images also showed arc clouds on the fringes of the eastern half of
the circulation, indicative of dry air entrainment. A satellite
classification of T2.0 from both SAB at 0000 UTC is used to maintain
the initial intensity at 30 kt.

Any opportunity for the depression to strengthen is expected to be
in the very short term. Water vapor imagery shows the cyclone
moving into a region dominated by very dry mid- to
upper-tropospheric air. The dry air, in combination with lower sea
surface temperatures and greater atmospheric stability, should
result in weakening after 24 to 36 hours. Global models show
the system opening up into a trough in about 3 days in an
increasingly unfavorable environment, around the time it crosses
140W. Like the previous forecast, this one shows little
intensification, followed by weakening. However, dissipation is
predicted much sooner (by 96 hours) based on the latest guidance.

The initial motion estimate is 290/12. A low- to mid-level ridge
over the subtropical eastern Pacific should steer the cyclone on a
west-northwestward course during the next few days. The model
solutions diverge to some degree after 12 to 24 hours, due to
their handling of the strength of this feature. The GFS and its
ensemble mean have a weaker ridge and are farthest north while the
ECWMF, with a stronger ridge, is on the southern side of the
guidance envelope. The new forecast track results in little
overall change from the previous one and is nearly split between
the ECMWF and GFS, near the multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 28/0300Z 16.0N 127.0W 30 KT 35 MPH
12H 28/1200Z 16.4N 128.7W 30 KT 35 MPH
24H 29/0000Z 16.9N 131.0W 35 KT 40 MPH
36H 29/1200Z 17.2N 133.3W 35 KT 40 MPH
48H 30/0000Z 17.5N 135.8W 30 KT 35 MPH
72H 31/0000Z 18.0N 141.3W 25 KT 30 MPH
96H 01/0000Z...DISSIPATED

$$
Forecaster Kimberlain