EPAC: ANDRES - Post-Tropical

[Yellow Evan]

[img][/img]
Back on the 1st june @120KNTS

I wonder if they'll up it to Cat.5 at the end of the season?

Nothing supports that sadly.

[Kingarabian]

[img][/img]
Back on the 1st june @120KNTS

I wonder if they'll up it to Cat.5 at the end of the season?

Nothing supports that sadly.

Hard to believe why. Wish someone would explain it.

I was thinking it wasn't completely vertically stacked.

[Yellow Evan]

Hard to believe why. Wish someone would explain it.

I was thinking it wasn't completely vertically stacked.

It never got higher than a 6.5 on the Dvorak scale from TAFB The reason it did not was because it was never able to get a white ring on the Dvorak enhancement satellite that was longer than a half a degree in width while also being able to sustain a WMG (9+C) eye. In the EPAC, that is difficult to sustain, partially due to their small size. Hence why the Dvorak underestimates small storms. Keep in mine though that the Dvorak was built for the WPAC.

Presentation-wise, yes, it was a bona fide Cat 5, but the evidence is not conclusive enough. CMISS ADT got as high as 6.7, which is just short.

[cycloneye]

TROPICAL STORM ANDRES DISCUSSION NUMBER 27
NWS NATIONAL HURRICANE CENTER MIAMI FL EP012015
200 PM PDT WED JUN 03 2015

Despite the limited and diminishing deep convection associated with
Andres, a 1304Z RapidScat scatterometer pass indicated at least 50
kt in the western - presumably the weaker - semicircle. Thus it
appears that Andres was more intense earlier today than originally
analyzed. Current subjective Dvorak and the ADT intensity estimates
for Andres have dropped to 35-45 kt. Given the likely low bias
indicated in the earlier Dvorak estimates, the initial intensity is
kept at 50 kt.

Andres should continue to be convectively challenged because it
is anticipated to remain over cool water, embedded in dry stable
air, and affected by increasingly strong vertical shear. Steady
weakening is likely and the system should become a remnant low by
Friday, if not earlier, and then dissipate in about five days. The
official intensity forecast is based upon the multi-model variable
intensity guidance - IVCN - and is unchanged from the previous
advisory.

Identifying the center of Andres this afternoon is quite
straightforward as the center is exposed southwest of the remaining
deep convection. The tropical storm is moving toward the northwest
at 5 kt, primarily due to steering induced by a deep-layered ridge
to its northeast. However, the cyclone will shortly be situated
within a col region with little steering flow and Andres should
meander on Thursday and Friday. In about three days, the remnant
low of Andres should move east-southeastward as it gets swept up the
by large circulation of Hurricane Blanca to its east. The official
track forecast is based upon the multi-model variable track guidance
- TVCN - of which the member models remain tightly clustered. This
new track prediction lies just slightly south of that from the
previous advisory.

FORECAST POSITIONS AND MAX WINDS

INIT 03/2100Z 19.9N 125.4W 50 KT 60 MPH
12H 04/0600Z 20.1N 125.4W 40 KT 45 MPH
24H 04/1800Z 20.0N 125.1W 30 KT 35 MPH
36H 05/0600Z 19.9N 124.9W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 05/1800Z 19.6N 124.6W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 06/1800Z 18.9N 123.4W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 07/1800Z 17.9N 121.1W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 08/1800Z...DISSIPATED

$$
Forecaster Landsea

[cycloneye]

TROPICAL STORM ANDRES DISCUSSION NUMBER 28
NWS NATIONAL HURRICANE CENTER MIAMI FL EP012015
800 PM PDT WED JUN 03 2015

Andres continues to generate a small area of convection to the
northeast of the center despite being over sea surface temperatures
near 24C. Satellite intensity estimates continue to decrease, and
the initial intensity is set at 45 kt based on continuity from the
previous advisory and a 45-kt satellite intensity estimate from
TAFB. Cold water and increasing vertical wind shear should cause
Andres to steadily weaken through the forecast period. The cyclone
is expected to weaken to a tropical depression within 24 hours,
degenerate to a remnant low in about 36 hours, and dissipate
completely after 96 hours.

Andres has turned northward over the past several hours with the
initial motion of 010/3. The cyclone is likely to be situated
within a col region with little steering flow during the next 48
hours or so with only a slow motion expected. After that time, a
somewhat faster motion toward the southeast or east-southeast should
occur as the large circulation of Hurricane Blanca to the east
becomes the main steering influence. The new forecast track has
been nudged a little south of the previous track after 24 hours and
lies near the model consensus.


FORECAST POSITIONS AND MAX WINDS

INIT 04/0300Z 20.2N 125.2W 45 KT 50 MPH
12H 04/1200Z 20.3N 125.0W 35 KT 40 MPH
24H 05/0000Z 20.1N 124.7W 30 KT 35 MPH
36H 05/1200Z 19.8N 124.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 06/0000Z 19.4N 124.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 07/0000Z 18.5N 123.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 08/0000Z 17.5N 120.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 09/0000Z...DISSIPATED

$$
Forecaster Beven

[cycloneye]

TROPICAL STORM ANDRES DISCUSSION NUMBER 29
NWS NATIONAL HURRICANE CENTER MIAMI FL EP012015
200 AM PDT THU JUN 04 2015

The cloud pattern of Andres is deteriorating quickly this morning
with the center of circulation becoming exposed well to the west of
the dissipating deep convection. The ambiguity solution of an
earlier 0222 UTC ISS-RapidScat pass showed a few believable 45 kt
winds to the northeast of the surface center. Since that time,
however, the deep convection in that particular area has decreased
in coverage and the cloud tops have warmed considerably. Therefore,
the initial intensity is decreased to 40 kt for this advisory, and
also agrees with a blend of the satellite intensity estimates from
TAFB and SAB. Since Andres is forecast to remain over sub-24
degrees Celsius waters and within a harsh vertical shear
environment, the cyclone is expected to weaken and become a remnant
low in 24 hours or less. The NHC intensity forecast, which is
similar to the IVCN consensus, calls for Andres to further weaken
and become a post-tropical remnant low within 24 hours, followed by
dissipation in 4 days.

Andres has barely moved during the past 6 hours, and appears
to be drifting northeastward with an initial motion of 045/2 kt.
The cyclone is forecast to turn gradually eastward later today and
then east-southeastward tonight within a weak low to mid-level
steering current. For the remaining portion of the forecast, the
low is expected to gradually accelerate and move toward the
southeast within the peripheral flow of Hurricane Blanca situated
several hundred miles to its east.

The initial wind radii have been adjusted based on a recent
ISS-RapidScat overpass, which showed a slightly larger extent of
tropical-storm-force winds over the northeast quadrant, and a
smaller area over the southern semi-circle.


FORECAST POSITIONS AND MAX WINDS

INIT 04/0900Z 20.2N 124.9W 40 KT 45 MPH
12H 04/1800Z 20.2N 124.8W 35 KT 40 MPH
24H 05/0600Z 19.9N 124.4W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 05/1800Z 19.5N 124.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 06/0600Z 19.0N 124.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 07/0600Z 18.0N 122.4W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 08/0600Z...POST-TROP/REMNT LOW

$$
Forecaster Roberts

[cycloneye]

TROPICAL STORM ANDRES DISCUSSION NUMBER 30
NWS NATIONAL HURRICANE CENTER MIAMI FL EP012015
800 AM PDT THU JUN 04 2015

Andres continues to weaken. The mid-level center of the cyclone
appears to have decoupled from the low-level circulation about 12
hours ago, and only a small area of deep convection remains nearly
two degrees removed from the center. The initial intensity is
lowered to 35 kt based on a blend of satellite intensity estimates
and on the assumption of some decrease in the winds since an
overnight ASCAT pass. Strong west-southwesterly shear and very
unfavorable thermodynamic factors should result in a continued spin
down of the cyclone, and global models show the circulation of
Andres degenerating into an open trough between 48 and 72 hours.
The NHC official forecast shows remnant low status in 12 hours and
dissipation a day earlier than the previous forecast.

Andres is drifting toward the east, and the initial motion estimate
is 095/03. Now that Andres has become fully decoupled and therefore
a shallow cyclone, it should be steered by the low-level flow which
is partially controlled by a low-level ridge to its northwest.
However, Andres should feel the tug by the large circulation of
Hurricane Blanca well to the east. The resultant flow should
produce a general southeastward motion until dissipation.

FORECAST POSITIONS AND MAX WINDS

INIT 04/1500Z 20.1N 124.5W 35 KT 40 MPH
12H 05/0000Z 20.0N 124.3W 30 KT 35 MPH...POST-TROP/REMNT LOW
24H 05/1200Z 19.7N 123.9W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 06/0000Z 19.1N 123.6W 20 KT 25 MPH...POST-TROP/REMNT LOW
48H 06/1200Z 18.7N 123.2W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 07/1200Z...POST-TROP/REMNT LOW

$$
Forecaster Kimberlain

[cycloneye]

By Andres but you did a good job of making records.

POST-TROPICAL CYCLONE ANDRES DISCUSSION NUMBER 31
NWS NATIONAL HURRICANE CENTER MIAMI FL EP012015
200 PM PDT THU JUN 04 2015

Although the low-level center of Andres remains intact, organized
deep convection has been absent from the center for more than 12
hours. In addition, what minimal convection remains is displaced a
considerable distance to the northeast of the center. On this
basis, Andres is being designated as a remnant low, and advisories
are being terminated at this time. Gradual weakening of the vortex
is expected to continue during the next couple of days due to
unfavorable environmental conditions, and global models show Andres
degenerating into an open trough by Saturday. The NHC forecast
calls for dissipation between 48 and 72 hours.

The initial motion estimate is 095/03. Now a shallow system, the
remnants of Andres are expected to be primarily steered by the
combination of low-level ridging to the northwest, along with a tug
by the large circulation of Hurricane Blanca to the east. This
should induce a slow east-southeastward to southeastward motion
until complete dissipation.

For additional information on this remnant low please see High
Seas Forecasts issued by the National Weather Service...under
AWIPS header NFDHSFEPI and WMO header FZPN01 KWBC.

FORECAST POSITIONS AND MAX WINDS

INIT 04/2100Z 20.1N 124.2W 30 KT 35 MPH
12H 05/0600Z 20.0N 124.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
24H 05/1800Z 19.7N 123.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 06/0600Z 19.1N 123.2W 20 KT 25 MPH...POST-TROP/REMNT LOW
48H 06/1800Z 18.7N 122.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 07/1800Z...DISSIPATED

$$
Forecaster Kimberlain