EPAC: LESTER - Post-Tropical

[Steve820]

The forecast is bringing it up to a hurricane on Friday. My personal prediction is C2 strength, but I think we cannot rule out a major hurricane.

[Yellow Evan]

26/0000 UTC 17.0N 113.4W T3.0/3.0 LESTER -- East Pacific

[Ntxw]

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

----- Current Analysis -----
Date : 26 AUG 2016 Time : 000000 UTC
Lat : 17:03:28 N Lon : 113:44:14 W


CI# /Pressure/ Vmax
4.2 / 986.8mb/ 69.8kt


Final T# Adj T# Raw T#
4.2 4.2 4.2

Center Temp : -72.1C Cloud Region Temp : -68.0C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[Yellow Evan]

Code: Select all

EP, 13, 2016082600,   , BEST,   0, 169N, 1135W,  50, 1000, TS,  34, NEQ,   40,   20,   20,   40, 1012,  150,  20,   0,   0,   E,   0,    ,   0,   0,     LESTER, M,
EP, 13, 2016082600,   , BEST,   0, 169N, 1135W,  50, 1000, TS,  50, NEQ,   20,    0,    0,    0, 1012,  150,  20,   0,   0,   E,   0,    ,   0,   0,     LESTER, M,


[Kingarabian]

Looks like a small eye...?

[cycloneye]

TROPICAL STORM LESTER DISCUSSION NUMBER 6
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016
900 PM MDT THU AUG 25 2016

Satellite images reveal that the cloud pattern has not changed very
much during the past several hours, and deep convection is not as
strong as earlier today. Some arc clouds have been moving away from
the cyclone, suggesting that Lester is not intensifying at this
time. This is confirmed by the latest Dvorak estimates which
still lead to an intensity of 50 kt. Nevertheless, Lester's
upper-level outflow is well established and, with low shear and
warm waters in its future path, strengthening is in order.
Thus, Lester is forecast to become a hurricane in a day or so. By
the end of the forecast period, cooler waters should induce gradual
weakening. The NHC forecast is basically the same as the previous
one.

Lester has slowed down a little bit and is now moving toward the
west or 270 degrees at 5 kt. The cyclone should resume a west-
northwest track soon toward a current weakness of the ridge.
However, in about 2 days, the ridge should amplify and build
westward, and this pattern should steer Lester westward through
the rest of the forecast period. Given that the steering currents
are expected to be very well established, tracks models are
in very good agreement. The NHC forecast follows the multi-model
consensus and has not deviated very much from the previous official
prediction.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0300Z 17.0N 113.8W 50 KT 60 MPH
12H 26/1200Z 17.4N 114.6W 55 KT 65 MPH
24H 27/0000Z 17.8N 115.9W 65 KT 75 MPH
36H 27/1200Z 18.0N 117.5W 70 KT 80 MPH
48H 28/0000Z 18.0N 119.5W 75 KT 85 MPH
72H 29/0000Z 18.5N 124.0W 80 KT 90 MPH
96H 30/0000Z 18.5N 129.5W 80 KT 90 MPH
120H 31/0000Z 18.5N 134.5W 75 KT 85 MPH

$$
Forecaster Avila

[cycloneye]

TROPICAL STORM LESTER DISCUSSION NUMBER 7
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016
300 AM MDT FRI AUG 26 2016

While Lester continues to produce a large area of cold cloud tops,
recent microwave imagery suggests that the storm is being affected
by vertical wind shear and dry air entrainment that is displacing
the convection mostly to the east and northeast of the center. A
recent ASCAT-B overpass indicated 45-50 kt winds about 40 n mi
northeast of the center, and based on this the initial intensity
remains 50 kt.

The microwave data show that Lester has moved westward for the
past several hours, with the initial motion now 280/6. The cyclone
should turn west-northwestward later today as it moves toward a
weakness in the subtropical ridge. After 12-24 hours, Lester
should resume a westward track with an increase in forward speed as
the ridge strengthens and builds westward. The track model
guidance is in excellent agreement with this scenario, and the new
forecast track is near the center of the guidance envelope. The
new forecast is a little to the south of the previous forecast
based on the current position and motion.

The dynamical models forecast the shear to decrease over the next
24 hours and remain low for the rest of the forecast period, which
should allow Lester to again intensify. The forecast track keeps
the cyclone over relatively warm water for about 72 hours, so the
intensity forecast calls for gradual strengthening during that
time. Subsequently, the waters cool a little along the forecast
track, and the intensity forecast thus shows some weakening. The
new intensity forecast is similar to the previous forecast, except
slightly weaker during the first 24 hours due to the shear.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0900Z 16.9N 114.5W 50 KT 60 MPH
12H 26/1800Z 17.1N 115.5W 55 KT 65 MPH
24H 27/0600Z 17.3N 116.9W 60 KT 70 MPH
36H 27/1800Z 17.4N 118.7W 70 KT 80 MPH
48H 28/0600Z 17.4N 120.8W 75 KT 85 MPH
72H 29/0600Z 17.5N 126.0W 80 KT 90 MPH
96H 30/0600Z 17.5N 131.5W 80 KT 90 MPH
120H 31/0600Z 17.5N 136.0W 75 KT 85 MPH

$$
Forecaster Beven

[cycloneye]

TROPICAL STORM LESTER DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016
800 AM PDT FRI AUG 26 2016

It appears that northwesterly shear and dry air entrainment is
continuing to prevent Lester from strengthening. The deep
convection associated with the tropical cyclone continues to burst,
but there is little evidence of banding features at this time.
Subject Dvorak intensity estimates range from 45 to 55 kt from SAB
and TAFB, and the earlier ASCAT data suggests that the intensity was
around 45 to 50 kt, so the initial wind speed will remain 50 kt for
this advisory. The shear is expected to decrease very soon, which
favors some intensification while Lester remains over warm water
during the next few days. Nearby dry air could occasionally
interrupt the intensification process during this time, so only
gradually strengthening is anticipated through 72 hours. After that
time, slightly cooler waters and a more stable airmass near the
track could cause some weakening by the end of the forecast period.

Lester is moving westward or 280/6. A strong mid- to upper-level
ridge centered well west of the Baja California is expected to
remain intact through the middle of next week. This ridge should
steer Lester westward at a little faster forward speed throughout
the entire forecast period. The guidance is in very good agreement
with this scenario, and the new NHC track is essentially an update
of the previous advisory, and lies near the middle of the guidance
envelope.

FORECAST POSITIONS AND MAX WINDS

INIT 26/1500Z 17.1N 115.0W 50 KT 60 MPH
12H 27/0000Z 17.3N 116.0W 55 KT 65 MPH
24H 27/1200Z 17.4N 117.6W 60 KT 70 MPH
36H 28/0000Z 17.4N 119.7W 70 KT 80 MPH
48H 28/1200Z 17.5N 122.1W 75 KT 85 MPH
72H 29/1200Z 17.5N 127.6W 80 KT 90 MPH
96H 30/1200Z 17.5N 132.8W 80 KT 90 MPH
120H 31/1200Z 17.2N 137.5W 75 KT 85 MPH

$$
Forecaster Brown

[Yellow Evan]

26/1800 UTC 17.6N 115.0W T3.5/3.5 LESTER -- East Pacific

[Kingarabian]

26/1800 UTC 17.6N 115.0W T3.5/3.5 LESTER -- East Pacific

How is this a 3.5?

[Yellow Evan]

Curved banding wrapped .8+ away around the center.

[cycloneye]

...LESTER EXPECTED TO BECOME A HURRICANE TONIGHT OR SATURDAY...


SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...17.6N 115.8W
ABOUT 530 MI...850 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...995 MB...29.39 INCHES




TROPICAL STORM LESTER DISCUSSION NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016
200 PM PDT FRI AUG 26 2016

After the convection associated with Lester appeared to be rather
shapeless in infrared satellite imagery overnight, visible pictures
indicate that there has been a significant increase in organization
today. Although the convective clouds tops are not very cold, a
ragged banding eye feature has become apparent within the past
couple of hours. As a result, Dvorak T-numbers have risen to 4.0
and 3.5 from TAFB and SAB respectively, and the initial wind speed
has been increased to 60 kt for this advisory. The center has
passed about 50 n mi southwest of Clarion Island during the past few
hours, and a weather station on that Island has reported sustained
winds of 46 kt with a gust to 62 kt.

Lester is forecast to move over warm water and within a low shear
environment during the next 2 to 3 days, which should result in
steady strengthening. Late in the forecast period, slightly cooler
waters and less favorable thermodynamic conditions are likely to
induce some weakening. The NHC
forecast calls for Lester to become a hurricane tonight, which is
in line with most of the intensity guidance. Later in the period,
the NHC wind speed prediction is a little above the intensity
consensus and SHIPS guidance, but is in good agreement with the
Florida State Superensemble.

Recent satellite fixes and ASCAT data indicate that Lester is
centered a little north of the previous position, and the latest
initial motion estimate is west-northwestward at about 6 kt. The
forecast track reasoning remains unchanged as a strong mid- to
upper-level ridge is forecast to remain over the eastern Pacific to
the west of the Baja California through the middle of next week.
Lester is expected to turn almost due westward by Saturday and
remain on that heading during the next 5 days. The track guidance
remains in excellent agreement, but the more northward initial
position required a northward adjustment to the NHC track forecast.

The wind radii have been adjusted outward based on the observations
from Clarion Island and recent ASCAT data.

FORECAST POSITIONS AND MAX WINDS

INIT 26/2100Z 17.6N 115.8W 60 KT 70 MPH
12H 27/0600Z 17.8N 116.9W 65 KT 75 MPH
24H 27/1800Z 17.9N 118.7W 70 KT 80 MPH
36H 28/0600Z 18.0N 120.9W 75 KT 85 MPH
48H 28/1800Z 18.0N 123.3W 80 KT 90 MPH
72H 29/1800Z 18.0N 128.7W 80 KT 90 MPH
96H 30/1800Z 18.0N 134.2W 80 KT 90 MPH
120H 31/1800Z 18.0N 139.5W 75 KT 85 MPH

$$
Forecaster Brown

[Alyono]

18Z MU has a devastating landfall on Maui just after the one ahead of it makes landfall

[Kingarabian]

Time for an upgrade.

[Yellow Evan]

Easily a T4.0, given how well bands are wrapping around the center.

[Kingarabian]

TXPZ23 KNES 270017
TCSENP

A. 13E (LESTER)

B. 27/0000Z

C. 17.9N

D. 116.1W

E. THREE/GOES-W

F. T3.5/3.5/D0.5/24HRS

G. IR/EIR/VIS

H. REMARKS...CURVED BANDING WRAPS 9/10 FOR A DT OF 3.5. MET AND PT
AGREE. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...VELASCO

[Yellow Evan]

Code: Select all

EP, 13, 2016082700,   , BEST,   0, 178N, 1161W,  60,  990, TS,  34, NEQ,   80,   60,   40,   70, 1011,  175,  25,   0,   0,   E,   0,    ,   0,   0,     LESTER, D,
EP, 13, 2016082700,   , BEST,   0, 178N, 1161W,  60,  990, TS,  50, NEQ,   40,   20,    0,   30, 1011,  175,  25,   0,   0,   E,   0,    ,   0,   0,     LESTER, D,


[Kingarabian]

Code: Select all

EP, 13, 2016082700,   , BEST,   0, 178N, 1161W,  60,  990, TS,  34, NEQ,   80,   60,   40,   70, 1011,  175,  25,   0,   0,   E,   0,    ,   0,   0,     LESTER, D,
EP, 13, 2016082700,   , BEST,   0, 178N, 1161W,  60,  990, TS,  50, NEQ,   40,   20,    0,   30, 1011,  175,  25,   0,   0,   E,   0,    ,   0,   0,     LESTER, D,


Oh well. Eye is evident on microwave. At least warrants a cat. 1 hurricane.

[Kingarabian]

...LESTER DEVELOPED AN EYE AND IS NOW A HURRICANE...

ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM

HURRICANE LESTER DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL EP132016
800 PM PDT FRI AUG 26 2016

The satellite presentation has been gradually improving during
the past few hours, and an eye became evident on the 0200 UTC
night visible image. A convective ring was also observed on the last
SSMI microwave pass at 2344 UTC. On this basis, and a Dvorak
estimate from TAFB, the initial wind speed has been increased to 65
kt. Additional intensification is anticipated during the next 2 to 3
days while the cyclone continues to move over warm waters and
is embedded within light shear. By the end of the forecast period,
Lester will probably begin to weaken due to entrainment of drier
air. The NHC forecast follows very closely the model consensus, and
shows Lester as a hurricane moving into the Central Pacific in about
5 days.

The best estimate of the initial motion is toward the west or 280
degrees at 8 kt. Lester is embedded within a deep-layer easterly
flow on the south side of an amplifying subtropical ridge extending
from the Baja California peninsula westward across the Pacific. This
pattern strongly favors the continuation of a westward motion for
the next five days with some increase in forward speed. The steering
flow is forecast to be so well established that track models are
basically on top of each other, increasing the confidence in the
forecast. The NHC forecast is in the middle of the tighter-than-
normal guidance envelope, and does not deviate much from the
previous NHC prediction.


FORECAST POSITIONS AND MAX WINDS

INIT 27/0300Z 17.9N 116.5W 65 KT 75 MPH
12H 27/1200Z 18.0N 117.7W 65 KT 75 MPH
24H 28/0000Z 18.1N 119.8W 70 KT 80 MPH
36H 28/1200Z 18.2N 122.0W 75 KT 85 MPH
48H 29/0000Z 18.2N 124.5W 80 KT 90 MPH
72H 30/0000Z 18.5N 130.0W 80 KT 90 MPH
96H 31/0000Z 18.5N 136.0W 75 KT 85 MPH
120H 01/0000Z 18.0N 140.8W 70 KT 80 MPH

$$
Forecaster Avila

[cycloneye]

Ridge looks strong as forecast goes down in latitude at the end.