EPAC: LANE - Remnants - Discussion

[cycloneye]

EP, 92, 2024103118, , BEST, 0, 109N, 1255W, 25, 1010, LO

https://ftp.nhc.noaa.gov/atcf/btk/bep922024.dat

[cycloneye]

Central East Pacific (EP92):
Satellite-derived winds indicate that the area of low pressure
located a little over 1200 miles southwest of the southern tip of
the Baja California peninsula has become better defined this
afternoon. However, shower and thunderstorm activity remains
disorganized. Some further development of this system is possible
during the next couple of days while the low moves slowly to the
west-northwest. By late this weekend, environmental conditions are
expected to become less conducive to development.
* Formation chance through 48 hours...medium...40 percent.
* Formation chance through 7 days...medium...40 percent.

[Pasmorade]

Central East Pacific (EP92):
Shower and thunderstorm activity associated with an area of low
pressure located more than 1000 miles southwest of the southern tip
of the Baja California peninsula has become better organized today.
A tropical depression could form during the next couple of days
while the low moves slowly westward. By late this weekend, however,
environmental conditions are expected to become less conducive for
development.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...medium...60 percent.

[cycloneye]

Tropical Depression Thirteen-E Discussion Number 1
NWS National Hurricane Center Miami FL EP132024
200 PM PDT Fri Nov 01 2024

The area of low pressure located more than 1000 miles southwest of
the southern tip of the Baja California peninsula has continued to
become better organized this afternoon. An ASCAT pass early this
morning indicated a well-defined circulation, and deep convection
near the center has persisted throughout the day. A subjective
Dvorak estimate from TAFB at 18Z was T2.5, and objective satellite
intensity estimates suggest that the winds have increased to near 30
kt. Based on these data, advisories are initiated on Tropical
Depression Thirteen, with an initial intensity of 30 kt.

The initial motion of this tropical storm is westward at 270/6 kt.
The depression is expected to continue on a generally westward
trajectory during the next day or two as it is steered by a broad
mid-level ridge to the north of the system. The track guidance is in
good agreement for the next several days, and the official forecast
track represents a blend of the HCCA and TVCN consensus models.

The depression is expected to be a short-lived system. The intensity
forecast indicates that the depression will remain below tropical
storm status through the weekend, though a low-end tropical storm
cannot be ruled out. By late this weekend, vertical wind shear is
expected to increase significantly, and the system is expected to
dissipate into a remnant low after about two days. The NHC intensity
forecast is in the middle of the guidance envelope and is similar to
the IVCN consensus model.


FORECAST POSITIONS AND MAX WINDS

INIT 01/2100Z 11.2N 128.4W 30 KT 35 MPH
12H 02/0600Z 11.2N 129.3W 30 KT 35 MPH
24H 02/1800Z 11.2N 130.5W 30 KT 35 MPH
36H 03/0600Z 11.3N 131.9W 30 KT 35 MPH
48H 03/1800Z 11.3N 133.5W 30 KT 35 MPH
60H 04/0600Z 11.3N 135.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 04/1800Z...DISSIPATED

$$
Forecaster Hogsett

[Pasmorade]

Could this exceed most expectations and be Lane?

[cycloneye]

Tropical Depression Thirteen-E Discussion Number 2
NWS National Hurricane Center Miami FL EP132024
800 PM PDT Fri Nov 01 2024

The depression has changed little in organization during the past
several hours, with visible and microwave satellite imagery showing
a cluster of convection near or a little east of the low-level
center. Satellite intensity estimates have changed little since the
last advisory, and thus the initial intensity remains 30 kt.

The initial motion remains 270/6 kt. The depression is expected to
continue moving generally westward during its lifetime as it is
steered by a broad mid-level ridge to the north. The latest track
guidance is similar to, but a little slower than, the earlier
guidance. Based on the latest aids, the new forecast track is also a
little slower, in the middle of the track guidance envelope.

The depression is currently in an environment of light shear and
over relatively warm water, and this should persist through 48 h.
While this environment seems favorable, the regional-hurricane
models and the global models show little strengthening during this
time. The intensity forecast follows these models and therefore
calls for little change in strength. However, any strengthening
would bring the system to tropical-storm strength, and the
statistical-dynamical models do forecast some intensification.
After 48 h, increasing shear is expected to cause this small system
to degenerate to a remnant low pressure area. A 72-h point as a
remnant low was added based on the global model guidance.


FORECAST POSITIONS AND MAX WINDS

INIT 02/0300Z 11.1N 129.0W 30 KT 35 MPH
12H 02/1200Z 11.1N 129.9W 30 KT 35 MPH
24H 03/0000Z 11.1N 131.1W 30 KT 35 MPH
36H 03/1200Z 11.2N 132.4W 30 KT 35 MPH
48H 04/0000Z 11.3N 133.9W 30 KT 35 MPH
60H 04/1200Z 11.3N 135.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 05/0000Z 11.3N 136.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 06/0000Z...DISSIPATED

$$
Forecaster Beven

[cycloneye]

Tropical Storm Lane Discussion Number 3
NWS National Hurricane Center Miami FL EP132024
200 AM PDT Sat Nov 02 2024

Satellite images indicate the center of the small tropical cyclone
is likely embedded underneath a cold dense overcast. The deep
convection has been quite persistent tonight, and as a result the
objective satellite intensity estimates have increased to around 40
kt, while the subjective Dvorak classifications from SAB and TAFB
range from 30-35 kt. Based on a blend of these data, the system is
upgraded to Tropical Storm Lane, with an initial intensity of 35 kt.

Lane is moving westward at 270/6 kt, and this general motion should
continue over the next few days as the storm moves along the
southern extent of a subtropical ridge to its north. There was a
slight southward shift in the guidance envelope this cycle, and the
updated NHC track prediction was nudged in that direction. Warm
sea-surface temperatures and low shear conditions could allow Lane
to strengthen a little more today. However, southwesterly shear is
expected to increase over the storm on Sunday, which should then
induce weakening of the small tropical cyclone through early next
week. Lane is forecast to degenerate to a post-tropical remnant low
in 48 h due to the negative effects of shear and drier environmental
air, and it could dissipate even sooner than forecast if the GFS
solution is correct.


FORECAST POSITIONS AND MAX WINDS

INIT 02/0900Z 11.1N 129.5W 35 KT 40 MPH
12H 02/1800Z 11.0N 130.5W 40 KT 45 MPH
24H 03/0600Z 11.0N 131.7W 35 KT 40 MPH
36H 03/1800Z 11.1N 133.1W 30 KT 35 MPH
48H 04/0600Z 11.2N 134.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 04/1800Z 11.2N 136.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 05/0600Z 11.3N 137.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 06/0600Z...DISSIPATED

$$
Forecaster Reinhart

[Pasmorade]

Seems like Lane's intensifying, albeit slowly

[cycloneye]

Tropical Storm Lane Discussion Number 4
NWS National Hurricane Center Miami FL EP132024
800 AM PDT Sat Nov 02 2024

Lane has continued to produce deep convection this morning over the
low-level center, with cold cloud tops near -80 C. Objective and
subjective satellite intensity estimates have increased and range
from 35 to 45 kt. Given the continued deep convection and using a
blend of these satellite estimates, the initial intensity is set to
40 kt for this advisory.

Lane continues to move westward at 270/6 kt, and this general motion
should continue over the next few days as the storm is steered by a
a subtropical ridge to the north. The latest NHC forecast is very
similar to the previous one, and remains near the latest consensus
aids.

Warm sea-surface temperatures and a relative low wind shear
environment could allow Lane to strengthen a little more today.
Environmental conditions become less favorable on Sunday as
southwesterly shear is forecast to increase over the system, and the
storm is forecast to move into a drier airmass early next week,
which should cause Lane to weaken. Lane is forecast to degenerate to
a post-tropical remnant low in about 48 h, although given the small
size of the system it could dissipate even sooner than forecast as
is depicted by some model fields, including the GFS.


FORECAST POSITIONS AND MAX WINDS

INIT 02/1500Z 11.3N 130.1W 40 KT 45 MPH
12H 03/0000Z 11.3N 131.0W 45 KT 50 MPH
24H 03/1200Z 11.3N 132.2W 35 KT 40 MPH
36H 04/0000Z 11.4N 133.6W 30 KT 35 MPH
48H 04/1200Z 11.4N 135.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
60H 05/0000Z 11.5N 136.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 05/1200Z 11.5N 137.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 06/1200Z...DISSIPATED

$$
Forecaster Kelly

[cycloneye]

Tropical Storm Lane Discussion Number 5
NWS National Hurricane Center Miami FL EP132024
200 PM PDT Sat Nov 02 2024

Satellite imagery depicts that Lane has been struggling the last
several hours, and appears more disorganized. The overall convective
canopy has deteriorated with warming cloud tops. Southwesterly shear
is starting to increase based on the latest visible images, and the
low-level center is located on the southwest edge of the convection.
Objective and subjective satellite intensity estimates have remained
steady throughout the day around 35 to 45 kt. Given the current
satellite presentation and using a blend of these satellite
estimates, the initial intensity is held at 40 kt for this advisory.

Lane continues to move generally westward at 270/6 kt, and this
general motion should continue over the next few days as the storm
is steered by a a subtropical ridge to the north. The latest NHC
forecast is very similar to the previous one, with a slight nudge to
the left.

Some intensity fluctuations are possible through today, though
southwesterly shear is starting to increase over the system. This
shear combined with a drier airmass along the forecast track will
lead to a steady weakening trend beginning on Sunday. Lane is
forecast to degenerate to a post-tropical remnant low in about 36 h,
although given the small size of the system it could dissipate even
sooner than forecast.


FORECAST POSITIONS AND MAX WINDS

INIT 02/2100Z 11.3N 130.3W 40 KT 45 MPH
12H 03/0600Z 11.3N 131.4W 40 KT 45 MPH
24H 03/1800Z 11.2N 132.6W 35 KT 40 MPH
36H 04/0600Z 11.3N 133.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
48H 04/1800Z 11.4N 135.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 05/0600Z...DISSIPATED

$$
Forecaster Kelly

[Sciencerocks]

[cycloneye]

Tropical Storm Lane Discussion Number 6
NWS National Hurricane Center Miami FL EP132024
800 PM PDT Sat Nov 02 2024

Lane's presentation on satellite imagery is quickly becoming
disheveled. This evening, a small burst of deep convection has
attempted to reform a little east of the estimated center. However,
an earlier AMSR2 microwave pass at 2155 UTC suggested the low-level
center was starting to separate from this deep convection due to
moderate mid- to deep-layer southwesterly shear. A partial ASCAT-B
pass did show winds up to 40 kt near the center at around 18 UTC,
but given the degradation in Lane's structure since that time, the
initial intensity is being lowered to 35 kt, in best agreement with
the objective intensity estimates from AiDT and SATCON. Continued
southwesterly shear combined with increasingly dry environmental air
should result in Lane's demise as it loses identity within the
Intertropical Convergence Zone (ITCZ). The latest NHC forecast shows
Lane becoming a remnant low in 24 h and opening up into a trough in
48 h. This evolution could occur sooner than forecast given current
trends and the fact several hurricane-regional model trackers
lose the vortex over the next day or so.

Lane still appears to be moving slowly westward, at an estimated
270/5 kt. As Lane becomes a shallow circulation, it will be
primarily steered by the low-level trade wind flow on the north
side of the ITCZ, leading to a slow westward to west-southwestward
motion until the vortex dissipates. The latest NHC track
forecast is just a little south of the prior track, given the
southward shift in the guidance suite this cycle.


FORECAST POSITIONS AND MAX WINDS

INIT 03/0300Z 11.3N 130.7W 35 KT 40 MPH
12H 03/1200Z 11.2N 131.7W 30 KT 35 MPH
24H 04/0000Z 11.2N 133.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
36H 04/1200Z 11.2N 134.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 05/0000Z...DISSIPATED

$$
Forecaster Papin

[cycloneye]

Tropical Depression Lane Discussion Number 7
NWS National Hurricane Center Miami FL EP132024
100 AM PST Sun Nov 03 2024

Lane is fading fast. Strong southwesterly shear associated with the
flow on the southern side of a broad upper-level trough has
disrupted the circulation of the tropical cyclone. Recent
scatterometer data show that the low-level circulation center is
losing definition, and the maximum winds have decreased to 30 kt at
most. Enhanced infrared satellite imagery shows that most of the
associated deep convection, which was displaced well to the
northeast of the estimated center, is dissipating. Given the
current degradation of circulation and convection, the system is now
expected to degenerate into a remnant low in about 12 hours.

The initial motion is slightly south of west at around 5 kt. This
general motion should continue for the next couple of days while
the system is steered by the shallow low-level easterlies. The
official track forecast has again been shifted slightly southward
to conform to the latest numerical guidance.


FORECAST POSITIONS AND MAX WINDS

INIT 03/0900Z 11.2N 131.0W 30 KT 35 MPH
12H 03/1800Z 11.1N 132.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 04/0600Z 10.9N 133.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
36H 04/1800Z 10.7N 135.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
48H 05/0600Z...DISSIPATED

$$
Forecaster Pasch

[cycloneye]

Post-Tropical Cyclone Lane Discussion Number 8
NWS National Hurricane Center Miami FL EP132024
700 AM PST Sun Nov 03 2024

Lane has degenerated into a remnant low. The exposed low-level
circulation is well separated from deep convection associated with
the monsoon trough based on geostationary satellite imagery. The
low is expected to move just south of west for the next couple of
days in the near surface flow. Lane should open into a trough by
mid-week, however this could occur sooner. This is the last NHC
advisory on this system.


FORECAST POSITIONS AND MAX WINDS

INIT 03/1500Z 11.1N 132.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
12H 04/0000Z 11.0N 133.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 04/1200Z 10.9N 134.1W 20 KT 25 MPH...POST-TROP/REMNT LOW
36H 05/0000Z 10.7N 135.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
48H 05/1200Z...DISSIPATED

$$
Forecaster Bucci