EPAC: FOURTEEN-E - Remnants - Discussion

[cycloneye]

Tropical Depression Fourteen-E Discussion Number 5
NWS National Hurricane Center Miami FL EP142023
1100 AM HST Sun Sep 24 2023

Moderate (15-20 kt) deep-layer shear and an enveloping dry and
stable low- to mid-level atmosphere have taken their toll
on the depression. The cyclone has lacked organized deep
convection since last night and primarily consists of a swirl of
low cloud elements, with deep convection well south of the surface
center associated with the inter-tropical convergence zone. The
initial intensity remains 30 kt based on a Dvorak CI number of 2.0
from TAFB. Despite warm waters ahead of the depression's track, the
negative environmental contributions mentioned above should cause
the depression to weaken further while impeding deep convective
redevelopment. Subsequently, the cyclone is expected to degenerate
to a remnant low later tonight and open into a trough in 4 days, or
less.

The exposed surface circulation's initial motion is estimated to be
westward or 270/13 kt. The forecast track philosophy is unchanged.
Mid-tropospheric high pressure extending from the Baja California
peninsula to the western tropical East Pacific should steer the
cyclone on a generally westward track through Monday. A turn
toward the west-southwest is expected on Tuesday within the
low-level tradewind steering flow through dissipation. The official
forecast is an update of the previous one and is based on the
various consensus aids.


FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 15.2N 125.5W 30 KT 35 MPH
12H 25/0600Z 15.3N 127.5W 30 KT 35 MPH...POST-TROP/REMNT LOW
24H 25/1800Z 15.1N 130.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 26/0600Z 14.7N 132.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 26/1800Z 13.8N 135.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 27/0600Z 12.7N 139.2W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 27/1800Z 11.5N 142.6W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 28/1800Z...DISSIPATED

$$
Forecaster Roberts

[Sciencerocks]

[cycloneye]

Bye.

Post-Tropical Cyclone Fourteen-E Discussion Number 6
NWS National Hurricane Center Miami FL EP142023
800 PM PDT Sun Sep 24 2023

Significant deep convection associated with the depression
dissipated about 18 hours ago. Minor shower and thunderstorm
activity has been ongoing since earlier this afternoon just south of
the center, but it is not large enough in areal coverage to be
considered organized and it has recently been waning. The latest
Dvorak estimates are T1.0/2.0 from TAFB and Too Weak to Classify
from SAB, therefore the system is being declared a remnant low with
maximum winds of 25 kt.

The remnant low is expected to move westward or west-southwestward
at 12-14 kt within the trade wind flow during the next couple of
days. Strong northwesterly mid-level shear is currently affecting
the low, and the shear is expected to increase within a deeper layer
of the atmosphere over the next 24 hours. This, along with a dry
and subsident environment, should prevent significant deep
convection from redeveloping, although occasional bursts of
convection cannot be ruled out. The NHC forecast now shows the low
opening up into a trough and dissipating by 48 hours, although this
could occur sooner according to the GFS and ECMWF forecast surface
wind fields.

For additional information on the remnant low please see High Seas
Forecasts issued by the National Weather Service, under AWIPS
header NFDHSFEPI, WMO header FZPN02 KWBC, and on the web at
ocean.weather.gov/shtml/NFDHSFEPI.php


FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 15.0N 126.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
12H 25/1200Z 14.9N 128.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 26/0000Z 14.6N 131.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 26/1200Z 13.9N 134.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 27/0000Z...DISSIPATED

$$
Forecaster Berg

[Teban54]

Right after the advisory declared it a remnant low: