EPAC: FRANK - Post-Tropical

[1900hurricane]

I'm not sure if Frank tried to develop concentric eyewalls or just had one deeply wrapped curved band (based on previous passes, I'm leaning with the latter). Either way though, it hasn't exactly worked out for Frank thus far.

[Yellow Evan]

Code: Select all

EP, 07, 2016072500,   , BEST,   0, 199N, 1128W,  60,  992, TS,  34, NEQ,   60,   70,   40,   70, 1010,  150,  20,   0,   0,   E,   0,    ,   0,   0,      FRANK, D,  0,    ,    0,    0,    0,    0, genesis-num, 014,
EP, 07, 2016072500,   , BEST,   0, 199N, 1128W,  60,  992, TS,  50, NEQ,   40,   30,    0,   30, 1010,  150,  20,   0,   0,   E,   0,    ,   0,   0,      FRANK, D,  0,    ,    0,    0,    0,    0, genesis-num, 014,


[cycloneye]

TROPICAL STORM FRANK DISCUSSION NUMBER 14
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
900 PM MDT SUN JUL 24 2016

After the earlier burst of strong convection, thunderstorm activity
in the inner-core region of Frank has deteriorated with cloud tops
having warmed significantly since the previous advisory. Moreover, a
2217Z AMSU microwave pass indicated that the eyewall convection had
become fragmented. The initial intensity remains at 60 kt for this
advisory, which is close to the average of the 0000Z subjective and
objective satellite intensity estimates.

Frank has continued to slow down and is now moving 275/04 kt. Frank
has made a westerly jog for the past 12 h, possibly due to the sharp
increases and decreases in the inner-core structure during that
time. However, the consensus of the global and regional models calls
for the cyclone to resume a west-northwestward motion by early
Monday. That motion is forecast to throughout at least 72 h as Frank
moves along the southwestern periphery of a deep-layer subtropical
ridge. By 96-120 h, the cyclone is forecast to weaken to shallow
remnant low pressure system, which should then be steered more
westward by the low-level easterly trade wind flow. The official
forecast track is similar to the previous advisory track and follows
the consensus track model TVCN.

Although the intensity is forecast to remain steady for the next 24
hours, Frank is expected to remain over SSTs greater than 26 deg C
and in a low vertical wind shear environment during that time, which
should provide the cyclone with the opportunity to mix out the
inner-core dry air and still become a hurricane. By 36-48 h,
however, Frank will be moving over sub-26 deg C water, which should
start a slow but steady weakening trend, with the cyclone
degenerating into a remnant low by day 4. The new NHC intensity
forecast is essentially just an update of the previous advisory, and
closely follows the intensity consensus model IVCN.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 20.0N 113.0W 60 KT 70 MPH
12H 25/1200Z 20.2N 113.8W 60 KT 70 MPH
24H 26/0000Z 20.4N 114.8W 60 KT 70 MPH
36H 26/1200Z 20.7N 116.1W 55 KT 65 MPH
48H 27/0000Z 21.1N 117.6W 45 KT 50 MPH
72H 28/0000Z 22.3N 120.6W 35 KT 40 MPH
96H 29/0000Z 23.0N 123.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 30/0000Z 23.3N 125.2W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Stewart

[hurricanes1234]

Frank isn't looking good quite frankly...

[RL3AO]

Georgette stole all of Frank's potential intensification.

[cycloneye]

TROPICAL STORM FRANK DISCUSSION NUMBER 15
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
300 AM MDT MON JUL 25 2016

Deep convection associated with Frank has diminished considerably
since Sunday. Since the vertical shear over the storm is weak, the
likely cause for this decrease is the upwelling of cooler ocean
waters beneath the slow-moving cyclone. The current intensity
estimate is reduced to 55 kt in accordance with a Dvorak estimate
from SAB, and this may be generous. Since the storm is expected to
begin moving west-northwestward at a faster forward speed soon, it
should temporarily pass over a warmer ocean. Thus some slight
restrengthening is forecast within the next 24 hours. After that,
decreasing SSTs should induce gradual weakening. Frank is likely
to be reduced to a remnant low pressure system in 4 days or so, and
this could occur sooner than that. The official intensity forecast
is a blend of the latest SHIPS and LGEM guidance.

Frank had been quasi-stationary over the past several hours,
although recent images suggest a slightly north-of-west drift
at about 280/3 kt. The mid-level subtropical ridge to the north of
the tropical cyclone collapsed, causing a very weak steering
current. However, the global models predict that the ridge to the
north of Frank will rebuild over the next several days and this
should produce a west-northwestward motion with some acceleration.
Late in the forecast period, the shallow remnant low is likely to
move mostly westward in the low-level flow. The official forecast
is a little faster than the previous one and close to the model
consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 25/0900Z 20.1N 113.2W 55 KT 65 MPH
12H 25/1800Z 20.3N 114.0W 55 KT 65 MPH
24H 26/0600Z 20.6N 115.3W 60 KT 70 MPH
36H 26/1800Z 21.0N 117.0W 55 KT 65 MPH
48H 27/0600Z 21.6N 118.7W 45 KT 50 MPH
72H 28/0600Z 23.1N 122.2W 35 KT 40 MPH
96H 29/0600Z 24.0N 125.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 30/0600Z 24.5N 128.0W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Pasch

[cycloneye]

TROPICAL STORM FRANK DISCUSSION NUMBER 16
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
900 AM MDT MON JUL 25 2016

Deep convection is bursting near the center of Frank, with its
asymmetric pattern on infrared images suggesting that shear
continues to play a significant role in the storm's structure.
Intensity estimates have a rather wide spread this morning, from 35
to 60 kt. Since the storm overall looks a little better than
overnight, the initial 55-kt wind speed is kept the same from
earlier, although it could still be generous. Frank has about 24
hours left before it crosses the 26 deg C isotherm, which will
likely cause gradual weakening thereafter. The storm still has a
chance of intensify during the first 24 h, but the official forecast
reflects no significant change in intensity, partially due to
uncertainty in the initial wind speed. Frank is likely to become a
remnant low in about 3 days due to it moving over cool 23 deg C
waters. The latest forecast is a bit lower than the previous one
and remains close to a SHIPS/LGEM consensus.

Microwave data show that Frank has started to move slowly westward,
with an initial motion estimate of 280/5. All of the global models
predict the subtropical ridge to strengthen over the next couple of
days, which should steer the storm west-northwestward with some
acceleration. Late in the forecast period, the shallow remnant low
is likely to move mostly westward in the low-level flow. The model
spread has notably decreased since yesterday, with only some minor
speed differences. Thus, no significant changes were made to the
previous track forecast, which lies close to the dynamical model
consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 25/1500Z 20.4N 113.9W 55 KT 65 MPH
12H 26/0000Z 20.5N 114.7W 55 KT 65 MPH
24H 26/1200Z 20.9N 116.2W 55 KT 65 MPH
36H 27/0000Z 21.5N 118.0W 50 KT 60 MPH
48H 27/1200Z 22.3N 119.8W 45 KT 50 MPH
72H 28/1200Z 23.8N 123.1W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 29/1200Z 24.5N 125.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 30/1200Z 24.7N 128.5W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Blake

[hurricanes1234]

Georgette stole all of Frank's potential intensification.

Yep

But that was better imo because if Frank was the strong one it might have brought more damaging swells to the coast

[hurricanes1234]

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

----- Current Analysis -----
Date : 25 JUL 2016 Time : 163000 UTC
Lat : 20:25:39 N Lon : 114:00:44 W


CI# /Pressure/ Vmax
4.4 / 979.8mb/ 74.6kt


Final T# Adj T# Raw T#
4.4 4.4 2.2

Center Temp : -37.1C Cloud Region Temp : -42.5C

Scene Type : CURVED BAND with 0.42 ARC in LT GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : EAST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : MW HOLD
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 57km
- Environmental MSLP : 1012mb

Satellite Name : GOES15
Satellite Viewing Angle : 33.7 degrees

[cycloneye]

TROPICAL STORM FRANK DISCUSSION NUMBER 17
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
300 PM MDT MON JUL 25 2016

Frank has been a challenge to analyze today, with lots of
conflicting data. On the one hand, earlier microwave data showed a
mid-level eye feature, causing the CIMSS-ADT value to shoot up to
hurricane strength. On the other hand, the overall appearance of
Frank has deteriorated since yesterday in both the organization and
strength of its associated convection. A partial ASCAT pass also
indicated winds of only about 35 kt, although it missed the full
eastern semicircle. The ADT value looks much too high, and the
initial wind speed is set to 45 kt, between the 35 kt estimate from
SAB and the 55 kt one from TAFB.

Little change is expected with Frank for the next day or so until
it crosses the 26 deg C isotherm, which will likely cause gradual
weakening thereafter. Remnant low status is expected in 2 to 3
days when the storm moves over cool water. Intensity guidance has
dropped since this morning, and the latest NHC prediction reflects
this trend, on the low side of the intensity consensus.

The initial motion estimate remains 280/5. The subtropical ridge
should strengthen over the next couple of days, which should steer
the storm west-northwestward with some increase in forward speed.
The only significant disagreement in the model guidance, similar to
yesterday, is late in the forecast period regarding the handling of
the shallow remnant low. The model consensus has done a very good
job of smoothing through these differences with the low, and the
official forecast is close to that aid and the previous forecast.


FORECAST POSITIONS AND MAX WINDS

INIT 25/2100Z 20.6N 114.4W 45 KT 50 MPH
12H 26/0600Z 20.9N 115.4W 45 KT 50 MPH
24H 26/1800Z 21.3N 117.0W 45 KT 50 MPH
36H 27/0600Z 21.9N 118.8W 40 KT 45 MPH
48H 27/1800Z 22.7N 120.6W 35 KT 40 MPH
72H 28/1800Z 23.8N 123.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 29/1800Z 24.5N 126.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 30/1800Z...DISSIPATED

$$
Forecaster Blake

[cycloneye]

TROPICAL STORM FRANK DISCUSSION NUMBER 18
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
800 PM PDT MON JUL 25 2016

The areal coverage of the deep convection has been gradually
shrinking and only a small area of strong thunderstorms remains to
the northeast of the center. Recent SSMIS data reveals that the
low-level structure is becoming less organized, but the mid-level
circulation is still quite distinct. The cyclone has a vigorous
circulation, and based on continuity as well as the latest
Dvorak estimates, the initial intensity is kept at 45 kt.

The shear does not appear to be a problem for Frank, but a stable
environment and cooler waters along its path will likely result in
weakening. This will likely occur beyond 24 hours when the entire
circulation reaches cooler waters. The NHC forecast follows the
guidance trend, primarily the SHIPS model, and calls for Frank to
degenerate into a remnant low in about 3 days.

Initial motion is 285/06. Global models forecast that the ridge to
the north of Frank will remain steady for the next few days. This
pattern will continue to steer the cyclone on a general west-
northwest track with a slight increase in forward speed until
dissipation. There is basically no spread in the guidance from 12
through 72 hours, increasing significantly the confidence in
the track forecast.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0300Z 20.8N 115.0W 45 KT 50 MPH
12H 26/1200Z 21.1N 116.1W 45 KT 50 MPH
24H 27/0000Z 21.6N 117.8W 45 KT 50 MPH
36H 27/1200Z 22.3N 119.5W 35 KT 40 MPH
48H 28/0000Z 23.0N 121.2W 30 KT 35 MPH
72H 29/0000Z 24.0N 124.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 30/0000Z...DISSIPATED

$$
Forecaster Avila

[talkon]

000
WTPZ42 KNHC 260848
TCDEP2

TROPICAL STORM FRANK DISCUSSION NUMBER 19
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
200 AM PDT TUE JUL 26 2016

After a decrease in thunderstorm activity yesterday, deep
convection associated with Frank has recently increased in a
CDO-type pattern. The intensity of the storm is adjusted upward
slightly to 50 kt which is a blend of Dvorak T- and Current
Intensity-numbers from TAFB and SAB. Little change in strength is
expected in the short term since Frank will be over marginally warm
SSTs and in a weak shear environment today. Within 12 to 24 hours,
however, a weakening trend is likely to commence and the cyclone
should become a tropical depression within a couple of days or
sooner. The official intensity forecast is a little below the
latest model consensus.

Frank continues slowly west-northwestward or at about 285/6 kt.
The track forecast seems straightforward. A mid-level subtropical
ridge to the north of the cyclone is predicted by the global models
to build slightly over the next few days. This should result in
little change in heading but with some increase in forward speed
during the next 2-3 days. The official track forecast is close to
the latest dynamical model consensus, TVCN.

FORECAST POSITIONS AND MAX WINDS

INIT 26/0900Z 21.1N 115.7W 50 KT 60 MPH
12H 26/1800Z 21.4N 116.8W 50 KT 60 MPH
24H 27/0600Z 22.1N 118.7W 45 KT 50 MPH
36H 27/1800Z 22.8N 120.5W 40 KT 45 MPH
48H 28/0600Z 23.4N 122.1W 30 KT 35 MPH
72H 29/0600Z 24.3N 124.6W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 30/0600Z...DISSIPATED

$$
Forecaster Pasch

[1900hurricane]

Thee 12Z working best track has fake-out Frank back up to 60 kt.

[cycloneye]

HURRICANE FRANK DISCUSSION NUMBER 20
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
800 AM PDT TUE JUL 26 2016

After struggling during the last few days, Frank has become much
better organized overnight, with deeper and more symmetric
convection. A SSM/IS pass from a couple of hours ago also indicated
the development of a vertically aligned eye feature. The 12z
satellite intensity estimates were 65 kt and 55 kt from TAFB and
SAB. Since that time, the appearance of the cyclone has improved in
satellite imagery with the formation of a visible eye, so the
initial wind speed is set to 65 kt.

Frank has less than 24 hours before it moves over SSTs cooler than
26C. Although it is not explicitly forecast, the hurricane could
become strengthen a little more sometime before weakening begins on
Wednesday due to much cooler waters. Frank should lose all of its
convection and transition to a post-tropical cyclone in about 2 days
when it encounters cold waters of 22-23C. The NHC forecast is raised
from the previous one, primarily due to the initial conditions, then
is blended with the previous forecast and the intensity consensus
IVCN.

The hurricane has finally started to move, estimated at 290/8 kt.
This general track is predicted for the next couple of days while
Frank is steered by a restrengthened subtropical ridge. After 48
hours, Frank is expected to turn more westward when it becomes a
shallow remnant low. Little change is made to the previous NHC
forecast, except for a small westward shift at long range near the
dynamical model consensus.

Frank is the 5th hurricane to form in the eastern Pacific during
July. This is the most on record for July, eclipsing the previous
record of 4 previously set in 5 other years. Reliable records in
the eastern Pacific for hurricanes begin in 1971.


FORECAST POSITIONS AND MAX WINDS

INIT 26/1500Z 21.2N 116.6W 65 KT 75 MPH
12H 27/0000Z 21.6N 118.0W 65 KT 75 MPH
24H 27/1200Z 22.4N 119.8W 60 KT 70 MPH
36H 28/0000Z 23.1N 121.6W 50 KT 60 MPH
48H 28/1200Z 23.8N 123.2W 40 KT 45 MPH...POST-TROPICAL
72H 29/1200Z 24.4N 125.4W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 30/1200Z...DISSIPATED

$$
Forecaster Blake

[hurricanes1234]

Well, what do you know!

Just when it's forecast to have no chance of becoming a hurricane or restrengthening, it unexpectedly intensifies to a hurricane, the fifth in this hyperactive month.

[Ntxw]

Didn't see that coming

[Kingarabian]

Didn't see that coming

Expect the unexpected in the Eastern Pacific .

[Ntxw]

Tenacious is the word I'd use for the 2016 EPAC season. If you don't succeed just keep trying

[cycloneye]

HURRICANE FRANK DISCUSSION NUMBER 21
NWS NATIONAL HURRICANE CENTER MIAMI FL EP072016
200 PM PDT TUE JUL 26 2016

Frank has intensified a little more during the day, with a ragged
eye occasionally showing itself within the central dense overcast.
Dvorak estimates range from 65 to 75 kt, so the initial wind speed
is increased to 70 kt on the advisory. Frank should be near its
peak intensity since it is already moving over sub-26C waters with
vertical shear likely to increase overnight. Steady weakening
should commence by late Wednesday, and Frank is forecast to
transition into a post-tropical cyclone on Thursday when it
traverses cold waters of 22-23C. The official forecast is close to
the previous NHC prediction and the intensity consensus IVCN.

Frank continues to pick up some speed, now moving 285/9. A
subtropical ridge to the north of the hurricane should steer Frank
generally west-northwestward for the next couple of days. A
westward turn is likely after that time due to Frank becoming a
more shallow cyclone. While the individual models are bouncing
around in latitude at the end of the forecast period, the dynamical
model consensus has remained rock solid since the last advisory.
Thus, no change is made to the previous NHC track forecast, which
is near or just south of the model consensus throughout the period.


FORECAST POSITIONS AND MAX WINDS

INIT 26/2100Z 21.5N 117.6W 70 KT 80 MPH
12H 27/0600Z 22.0N 119.1W 65 KT 75 MPH
24H 27/1800Z 22.9N 121.0W 60 KT 70 MPH
36H 28/0600Z 23.8N 122.6W 50 KT 60 MPH
48H 28/1800Z 24.4N 123.8W 40 KT 45 MPH...POST-TROPICAL
72H 29/1800Z 24.5N 126.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 30/1800Z...DISSIPATED

$$
Forecaster Blake

[Kingarabian]

If the eye can warm we could be looking at the fourth major hurricane of the season.