EPAC: BLAS - Post-Tropical

[Alyono]

the ensembles are generally south of the deterministic models

[Kingarabian]

the ensembles are generally south of the deterministic models

I think it's a good time to begin discussions about Blas's track as the model forecasts enter the medium range.

The Euro is windshield wiping Blas's track from south of Hawaii to the north of Hawaii.
The GFS keeps Blas well north east of Hawaii but has been shifting west.

I think these two models are having a hard time deciding when the trough weakens the STR and how long it takes for the STR to rebuild.

[cycloneye]

I agree that RI is imminent.

 https://twitter.com/Adriansweather/status/749574021713371136

[Kingarabian]

One of the nicest compact CDO's i've ever seen.

Looks like RI is about to begin or has begun. Need a microwave pass to confirm.

[cycloneye]

RI has begun.

EP, 03, 2016070312, , BEST, 0, 116N, 1098W, 45, 1003, TS

[Yellow Evan]

TXPZ21 KNES 031219
TCSENP
CCA

A. 03E (BLAS)

B. 03/1200Z

C. 11.7N

D. 109.4W

E. THREE/GOES-W

F. T3.0/3.0/D2.0/24HRS

G. IR/EIR/SWIR

H. REMARKS...CORRECTED DT. DT=3.5 BASED ON .9 BANDING ON LOG10
SPIRAL. PT=3.0. MET=2.5. FT IS BASED ON PT.

I. ADDL POSITIONS

NIL


...SCHWARTZ

[Yellow Evan]

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* IR SAT DATA AVAILABLE, OHC AVAILABLE *
* BLAS EP032016 07/03/16 12 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 45 51 56 61 67 81 91 99 104 107 105 98 88
V (KT) LAND 45 51 56 61 67 81 91 99 104 107 105 98 88
V (KT) LGEM 45 52 58 64 70 82 91 96 99 96 87 76 66
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 8 8 10 10 10 8 11 10 8 8 5 9 9
SHEAR ADJ (KT) -3 0 0 2 1 1 1 -2 0 3 4 3 7
SHEAR DIR 113 91 60 59 55 62 50 52 78 41 79 82 101
SST (C) 29.7 29.6 29.3 28.9 28.6 28.8 28.6 28.2 27.8 26.6 25.8 25.9 25.4
POT. INT. (KT) 162 161 158 154 151 153 151 147 143 130 121 122 116
200 MB T (C) -52.8 -52.6 -52.0 -52.5 -52.8 -51.8 -52.2 -51.7 -52.1 -51.3 -51.7 -51.2 -51.7
200 MB VXT (C) -0.3 -0.2 -0.2 0.0 0.1 0.3 0.4 0.7 0.8 0.6 0.6 0.6 0.7
TH_E DEV (C) 7 8 8 8 8 7 7 7 6 5 4 4 5
700-500 MB RH 71 68 70 68 70 73 72 68 67 67 66 66 60
MODEL VTX (KT) 18 19 20 21 22 27 30 33 37 41 42 40 38
850 MB ENV VOR 0 -1 -4 -7 -6 5 9 28 36 55 60 69 70
200 MB DIV 52 52 41 40 61 90 44 40 26 78 63 55 37
700-850 TADV 3 5 3 1 0 -3 -4 -4 -5 -1 -2 1 3
LAND (KM) 1003 1036 1080 1141 1199 1261 1344 1461 1584 1711 1801 1888 1975
LAT (DEG N) 11.6 11.9 12.2 12.5 12.8 13.2 13.8 14.3 14.7 15.3 16.1 16.8 17.5
LONG(DEG W) 109.8 110.8 111.8 112.9 114.0 116.2 118.4 120.7 123.0 125.2 127.1 129.0 130.7
STM SPEED (KT) 11 10 11 11 11 11 12 11 11 11 10 10 8
HEAT CONTENT 32 33 30 26 26 28 49 28 22 19 2 0 0

FORECAST TRACK FROM OFCI INITIAL HEADING/SPEED (DEG/KT):285/ 11 CX,CY: -10/ 3
T-12 MAX WIND: 30 PRESSURE OF STEERING LEVEL (MB): 518 (MEAN=586)
GOES IR BRIGHTNESS TEMP. STD DEV. 50-200 KM RAD: 18.2 (MEAN=14.5)
% GOES IR PIXELS WITH T < -20 C 50-200 KM RAD: 71.0 (MEAN=65.0)
PRELIM RI PROB (DV .GE. 30 KT IN 24 HR): 17.9

INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
6 12 18 24 36 48 60 72 84 96 108 120
----------------------------------------------------------
SAMPLE MEAN CHANGE 0. 0. 1. 1. 1. 1. 1. 1. 0. -1. -1. -2.
SST POTENTIAL 0. 1. 2. 4. 7. 10. 13. 15. 15. 15. 14. 13.
VERTICAL SHEAR MAG 0. 1. 1. 1. 2. 2. 2. 3. 4. 5. 5. 5.
VERTICAL SHEAR ADJ 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. -1.
VERTICAL SHEAR DIR 1. 1. 3. 4. 6. 8. 10. 11. 11. 12. 11. 10.
PERSISTENCE 3. 5. 6. 7. 7. 6. 5. 3. 2. 2. 1. -1.
200/250 MB TEMP. 0. 0. 0. -1. -2. -3. -3. -4. -4. -4. -4. -4.
THETA_E EXCESS 0. 0. 0. 1. 1. 1. 1. 1. 1. 0. 0. -1.
700-500 MB RH 0. 0. 0. 0. 1. 1. 1. 2. 2. 2. 2. 2.
MODEL VTX TENDENCY 0. 1. 2. 4. 11. 15. 21. 26. 31. 31. 27. 22.
850 MB ENV VORTICITY 0. 0. 0. 0. 0. 0. 1. 1. 1. 0. 0. 0.
200 MB DIVERGENCE 0. 0. 0. 0. 1. 2. 2. 1. 1. 2. 1. 1.
850-700 T ADVEC 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0. 0.
ZONAL STORM MOTION 0. 0. 1. 1. 1. 1. 2. 1. 1. 1. 1. 1.
STEERING LEVEL PRES 0. 0. 0. 0. -1. -1. -1. -1. -1. -1. -1. -1.
DAYS FROM CLIM. PEAK 0. 0. 0. 0. 0. 0. 0. -1. -1. -1. -2. -2.
GOES PREDICTORS 0. 0. -1. -1. -1. -1. -1. -1. -1. -1. -1. -1.
OCEAN HEAT CONTENT 0. 0. 0. 0. 1. 1. 1. 0. 0. 0. 0. 0.
----------------------------------------------------------
TOTAL CHANGE 6. 11. 16. 22. 36. 46. 54. 59. 62. 60. 53. 43.

CURRENT MAX WIND (KT): 45. LAT, LON: 11.6 109.8

** 2015 E. Pacific RI INDEX EP032016 BLAS 07/03/16 12 UTC **
(SHIPS-RII PREDICTOR TABLE for 30 KT OR MOREMAXIMUM WIND INCREASE IN NEXT 24-h)

Predictor Value RI Predictor Range Scaled Value(0-1) % Contribution
12 HR PERSISTENCE (KT): 15.0 -22.0 to 38.5 0.61 5.7
POT = MPI-VMAX (KT) : 112.3 40.3 to 144.5 0.69 4.5
HEAT CONTENT (KJ/cm2) : 29.4 0.0 to 75.9 0.39 3.2
STD DEV OF IR BR TEMP : 18.2 38.9 to 2.1 0.56 4.3
850-200 MB SHEAR (KT) : 9.2 18.9 to 1.4 0.56 3.9
MAXIMUM WIND (kt) : 45.0 22.5 to 132.0 0.63 3.8
D200 (10**7s-1) : 49.2 -11.0 to 135.3 0.41 1.5
BL DRY-AIR FLUX (w/m2): 144.8 638.0 to -68.2 0.70 0.0
2nd PC OF IR BR TEMP : 1.4 2.1 to -1.7 0.20 -0.3
% AREA WITH TPW <45 mm: 0.0 81.4 to 0.0 1.00 0.9

SHIPS Prob RI for 20kt/ 12hr RI threshold= 17% is 2.7 times sample mean ( 6.3%)
SHIPS Prob RI for 25kt/ 24hr RI threshold= 37% is 2.8 times sample mean (12.9%)
SHIPS Prob RI for 30kt/ 24hr RI threshold= 28% is 3.2 times sample mean ( 8.6%)
SHIPS Prob RI for 35kt/ 24hr RI threshold= 21% is 3.7 times sample mean ( 5.8%)
SHIPS Prob RI for 40kt/ 24hr RI threshold= 17% is 4.1 times sample mean ( 4.1%)
SHIPS Prob RI for 45kt/ 36hr RI threshold= 42% is 5.9 times sample mean ( 7.1%)
SHIPS Prob RI for 55kt/ 48hr RI threshold= 40% is 6.9 times sample mean ( 5.9%)

Matrix of RI probabilities
---------------------------------------------------------------------
RI (kt / h) | 20/12 | 25/24 | 30/24 | 35/24 | 40/24 | 45/36 | 55/48
---------------------------------------------------------------------
SHIPS-RII: 17.0% 36.6% 27.6% 21.3% 16.9% 42.1% 40.5%
Logistic: 17.1% 39.6% 18.0% 11.3% 5.5% 14.5% 11.5%
Bayesian: 1.0% 29.4% 13.6% 3.9% 1.1% 5.0% 18.8%
Consensus: 11.7% 35.2% 19.7% 12.2% 7.8% 20.5% 23.6%

## ANNULAR HURRICANE INDEX (AHI) EP032016 BLAS 07/03/16 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) ##

[Kingarabian]

The NHC is really conservative with a 100kt peak. I'm thinking we'll see 120-130kts easily.

[Darvince]

An almost perfect circle

[cycloneye]

 https://twitter.com/EricBlake12/status/749610712373178369

[RL3AO]

It really has the look of something that could be a major hurricane by tomorrow morning.

[cycloneye]

Up to 60 mph.

BULLETIN
TROPICAL STORM BLAS ADVISORY NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL EP032016
900 AM MDT SUN JUL 03 2016

...BLAS QUICKLY STRENGTHENING...
...FORECAST TO BECOME A HURRICANE BY MONDAY...


SUMMARY OF 900 AM MDT...1500 UTC...INFORMATION
----------------------------------------------
LOCATION...11.6N 110.3W
ABOUT 650 MI...1045 KM SW OF MANZANILLO MEXICO
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1001 MB...29.56 INCHES


TROPICAL STORM BLAS DISCUSSION NUMBER 3
NWS NATIONAL HURRICANE CENTER MIAMI FL EP032016
900 AM MDT SUN JUL 03 2016

Satellite imagery indicates a marked increase in organization of the
Blas' cloud pattern overnight, suggesting that the cyclone is
quickly intensifying. The center is located underneath a ball of
deep convection, the latter which appears to be a formative central
dense overcast. The large-envelope cyclone also has a lengthening
band that consists of very cold-topped convection in the shape of a
figure six. Satellite classifications are T3.0/45 kt and T3.5/55 kt
from SAB and TAFB at 1200 UTC, respectively. The initial intensity
is raised to 50 kt, based on a blend of the two intensity estimates.

The initial motion estimate is 285/11. Blas is forecast to move
along the southern periphery of a deep-layer subtropical ridge
centered over northern Mexico throughout the forecast period, which
should keep the cyclone on a general west-northwesterly course. The
model guidance is in very good agreement through 72 hours, but
diverges after that time. The GFS and its ensemble mean lie near
the previous forecast and is on the northern side of the guidance
envelope, while the ECMWF and its ensemble mean are much farther
south. The differences between the two models appear related to
subtle variations in the strength and position of the subtropical
ridge forecast after day 3. The NHC track forecast is adjusted a
bit south of the previous one, on the southern side of the guidance
envelope through 72 hours and near the multi-model consensus after
that time.

There does not appear to be anything obvious on the large-scale to
impede intensification over the next few days, except that the
cyclone will be very gradually departing the warmest waters over the
basin. The light-easterly-shear, moist environment and warm waters
should allow Blas to strengthen into a major hurricane as indicated
in about 48 hours. The official NHC forecast through that time is
heavily weighted toward the statistical guidance which is performing
well, considering the current developmental trend. By 96 hours,
even though the shear is forecast to remain low, the cyclone should
be moving over steadily cooler waters and entering a drier and more
stable environment. This should foster a weakening trend, though
the weakening will likely occur only gradually.

FORECAST POSITIONS AND MAX WINDS

INIT 03/1500Z 11.6N 110.3W 50 KT 60 MPH
12H 04/0000Z 12.1N 112.0W 60 KT 70 MPH
24H 04/1200Z 12.6N 114.1W 75 KT 85 MPH
36H 05/0000Z 13.1N 116.4W 90 KT 105 MPH
48H 05/1200Z 13.6N 118.7W 100 KT 115 MPH
72H 06/1200Z 14.6N 123.3W 105 KT 120 MPH
96H 07/1200Z 16.0N 127.7W 95 KT 110 MPH
120H 08/1200Z 17.3N 131.3W 85 KT 100 MPH

$$
Forecaster Kimberlain

[Yellow Evan]

Likely to peak around 125 knots given it's structure. CDO not quite as cold as you'd see for a storm with 140 knot potential, however. Not the type of storm that will produce CMG cloudtops.

[gatorcane]

First visibles, looking great

[Yellow Evan]

Inner core not there yet but getting there. Probs 50 knots still.

[cycloneye]

RL3AO you prediction looks spot on.

 https://twitter.com/EricBlake12/status/749660324475789312

[Kingarabian]

3.5/3.5 from SAB.

[Yellow Evan]

TXPZ21 KNES 031815
TCSENP

A. 03E (BLAS)

B. 03/1800Z

C. 12.0N

D. 110.7W

E. THREE/GOES-W

F. T3.5/3.5/D2.0/24HRS

G. IR/EIR/VIS/SSMIS

H. REMARKS...DT=3.9 BASED ON 1.25 DG CDO WITH .5 ADDED FOR
BANDING. PT=3.5. MET=3.0. FT IS BASED ON DT.

I. ADDL POSITIONS

03/1444Z 12.0N 110.3W SSMIS


...SCHWARTZ

DT should be 4.5 then, but why add for BF? DT=4.0 makes sense, so 60 knots is good right now.

[Yellow Evan]

Given its a partial pass and 50 knot barbs, 55 works, but might be a little conservative.

[Yellow Evan]

Code: Select all

   EP, 03, 2016070318,   , BEST,   0, 121N, 1109W,  55, 1001, TS,  34, NEQ,   60,   40,   30,   50, 1012,  220,  30,   0,   0,   E,   0,    ,   0,   0,       BLAS, M,  0,    ,    0,    0,    0,    0, genesis-num, 009,