CPAC: DARBY - Post-Tropical

[Kingarabian]

Annular hurricanes seem to make their own moist environment. Just Look at Darby plow through dry air:



Wouldn't be surprised to see Darby maintain its intensity longer than expected given the low shear ahead of it.

[Ntxw]

Worthy of a major. If Danny (ATL 2015) was a major it would be hypocrisy to say Darby isn't

[Yellow Evan]

Since 1230z, Darby has been to me at least worthy of a T5.5 in every frame but one, and may be nearing T6.0 right now. Can it sustain itself until 18z and get a T5.5 form SAB/TAFB?

[Yellow Evan]

Eye still warming.

----- Current Analysis -----
Date : 16 JUL 2016 Time : 160000 UTC
Lat : 17:59:24 N Lon : 124:05:06 W


CI# /Pressure/ Vmax
5.6 / 959.1mb/104.6kt


Final T# Adj T# Raw T#
5.6 5.6 5.6

Estimated radius of max. wind based on IR : 26 km

Center Temp : +12.7C Cloud Region Temp : -59.1C

Scene Type : EYE

[Yellow Evan]

Fairly steady state.

----- Current Analysis -----
Date : 16 JUL 2016 Time : 163000 UTC
Lat : 17:54:40 N Lon : 124:15:23 W


CI# /Pressure/ Vmax
5.6 / 959.1mb/104.6kt


Final T# Adj T# Raw T#
5.6 5.5 5.5

Estimated radius of max. wind based on IR : 26 km

Center Temp : +12.7C Cloud Region Temp : -57.6C

Scene Type : EYE

[JaxGator]

Impressive.
http://i1284.photobucket.com/albums/a56 ... 1468601474

[Yellow Evan]

Eye cooling, but all it needs is one more frame of WMG embedded in LG for a T5.5.

----- Current Analysis -----
Date : 16 JUL 2016 Time : 170000 UTC
Lat : 17:55:57 N Lon : 124:19:22 W


CI# /Pressure/ Vmax
5.6 / 959.1mb/104.6kt


Final T# Adj T# Raw T#
5.6 5.5 5.5

Estimated radius of max. wind based on IR : 26 km

Center Temp : +9.2C Cloud Region Temp : -58.2C

Scene Type : EYE

[cycloneye]

 https://twitter.com/EricBlake12/status/754369358323777537

[Yellow Evan]

Appears set for a T5.5 but barely. SAB's fix will be out soon.

[1900hurricane]

SAB actually goes 6.0

TXPZ24 KNES 161832
TCSENP

A. 05E (DARBY)

B. 16/1800Z

C. 18.0N

D. 124.4W

E. ONE/GOES-W

F. T6.0/6.0/D1.5/24HRS

G. IR/EIR/VIS

H. REMARKS...WMG EYE (283K) EMBEDDED IN LG AND SURROUNDED BY B YIELDS
A DT OF 6.0 WHICH INCLUDES 1.0 ADDED FOR EYE ADJUSTMENT. MET = 5.5 AND
PT = 6.0. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...KIBLER

[Yellow Evan]

Umm no. I don't see no WMG eye in latest frame. Please be consistent. There's either a WMG eye or a a B ring. There's not both in the same frame.

Code: Select all

TXPZ24 KNES 161832
TCSENP

A.  05E (DARBY)

B.  16/1800Z

C.  18.0N

D.  124.4W

E.  ONE/GOES-W

F.  T6.0/6.0/D1.5/24HRS

G.  IR/EIR/VIS

H.  REMARKS...WMG EYE (283K) EMBEDDED IN LG AND SURROUNDED BY B YIELDS
A DT OF 6.0 WHICH INCLUDES 1.0 ADDED FOR EYE ADJUSTMENT.  MET = 5.5 AND
PT = 6.0.  FT IS BASED ON DT.

I.  ADDL POSITIONS

    NIL


...KIBLER

[Yellow Evan]

----- Current Analysis -----
Date : 16 JUL 2016 Time : 180000 UTC
Lat : 17:58:36 N Lon : 124:27:19 W


CI# /Pressure/ Vmax
5.6 / 959.1mb/104.6kt


Final T# Adj T# Raw T#
5.5 5.7 5.7

Estimated radius of max. wind based on IR : 23 km

Center Temp : +8.8C Cloud Region Temp : -60.5C

Scene Type : EYE

[NotoSans]

NHC goes with 100.

EP, 05, 2016071618, , BEST, 0, 179N, 1245W, 100, 963, HU, 34, NEQ, 100, 70, 50, 70, 1009, 200, 20, 0, 0, E, 0, , 0, 0, DARBY, D, 0, , 0, 0, 0, 0, genesis-num, 011,

[Yellow Evan]

100 is likely a little conservative given TAFB plus SAB, but I understand there may be issues with surface mixing in these shallow SST's, although this is also the intensity there starts to be a low bias with Dvorak.

Code: Select all

EP, 05, 201607161800,  10, DVTS,         CI,  , 1790N, 12440W,      , 1, 102, 2,  960, 2, DVRK,    ,     ,     ,     ,     ,     ,  ,  ,  ,  ,  ,    ,  20, E,  TAFB,  EC,   VI, 1, 5555 /////,      ,   , GOES15,  CSC, T,                                     


[Kingarabian]

Hopefully ADT numbers climb before the next advisory.

[Kingarabian]

Also has been moving south of the NHC track. It should avoid the 23c waters if it continues doing so.

[Kingarabian]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 16 JUL 2016 Time : 193000 UTC
Lat : 17:59:53 N Lon : 124:44:40 W


CI# /Pressure/ Vmax
5.7 / 954.9mb/107.2kt


Final T# Adj T# Raw T#
5.7 5.9 5.9

Estimated radius of max. wind based on IR : 21 km

Center Temp : +11.4C Cloud Region Temp : -62.2C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

[Yellow Evan]

I'd go 110.

[Alyono]

I'm going 105 kts.

I came up with a 5.5 at 18Z. However, I am blending with other estimates

[cycloneye]

HURRICANE DARBY DISCUSSION NUMBER 21
NWS NATIONAL HURRICANE CENTER MIAMI FL EP052016
200 PM PDT SAT JUL 16 2016

Darby appears to have been strengthening during the day despite
moving over increasingly cooler waters. The deep convection is
becoming more symmetric, the eye has been warming intermittently,
and the hurricane appears to be losing some of its outer banding.
In fact, Darby has developed a marginal annular structure. Dvorak
estimates have generally risen since this morning, and the initial
intensity is raised to 100 kt. This makes Darby the second major
hurricane of the eastern North Pacific season.

Sea surface temperatures beneath Darby are currently around 25.5C
and will continue to decrease over the next few days. But, given
that vertical shear is expected to remain low through at least day
3, and the hurricane's marginal annular structure, Darby is likely
to remain relatively steady in intensity or only gradually weaken in
the short-term. Faster weakening is still expected later in the
forecast period due to the added effect of increasing shear.
Almost every reliable intensity model shows Darby weakening fast
during the next day or two. However, the HWRF model is a notable
outlier and keeps Darby as a hurricane at least through day 3. The
updated NHC intensity forecast is a little higher than the previous
forecast during the first 36 hours and is near the top end of the
main pack of intensity models.

The initial motion remains 285/9 kt. The subtropical ridge to the
north of Darby is weakening, but it should stay strong enough to
steer the hurricane west-northwestward or westward through the
entire forecast period. The new run of the ECMWF has sped up
compared to the other track models, but otherwise there is very
little spread in the guidance envelope. The updated NHC track
forecast is closest to an average of the GFS and ECMWF and is very
close to the previous forecast.

FORECAST POSITIONS AND MAX WINDS

INIT 16/2100Z 18.0N 124.9W 100 KT 115 MPH
12H 17/0600Z 18.3N 126.3W 90 KT 105 MPH
24H 17/1800Z 18.5N 128.1W 80 KT 90 MPH
36H 18/0600Z 18.8N 130.1W 70 KT 80 MPH
48H 18/1800Z 19.0N 132.2W 60 KT 70 MPH
72H 19/1800Z 19.7N 136.6W 50 KT 60 MPH
96H 20/1800Z 19.7N 141.1W 40 KT 45 MPH
120H 21/1800Z 18.7N 146.0W 35 KT 40 MPH

$$
Forecaster Berg