t02436

09Z升C1，將逐漸北上。

404
WTNT43 KNHC 030845
TCDAT3

Hurricane Leslie Discussion Number  28
NWS National Hurricane Center Miami FL       AL132018
500 AM AST Wed Oct 03 2018

Deep convection surrounding the center of Leslie has become better
organized overnight, with the development of a ragged eye in
infrared satellite images.  A 0552 UTC AMSR2 microwave overpass
revealed a well-defined low-level eye with a ring of broken
convection surrounding it.  T-numbers from both TAFB and SAB were
4.0 on the Dvorak scale, therefore the initial intensity has
been increased to 65 kt.  This makes Leslie the sixth hurricane
of the 2018 Atlantic hurricane season.

The hurricane is forecast to remain within favorable environmental
conditions consisting of warm water and low vertical wind shear
over the next day or two.  These conditions should allow for some
additional strengthening.  After 48 hours, Leslie will be moving
over cooler waters, which should induce gradual weakening later
in the period.

Leslie has become nearly stationary overnight, and it appears that
the cyclone's equatorward motion has likely come to an end.  A
shortwave trough to the northwest of the storm and a building ridge
to the east, are expected to allow Leslie to begin moving northward
by tonight.  A northward motion is then expected to continue over
the next 2-3 days, but by the weekend Leslie is predicted to turn
eastward as a broad trough dips southward over the north Atlantic.
The dynamical model guidance is in relatively good agreement on this
scenario and the new NHC track forecast is essentially an update of
the previous advisory.

Large swells generated by Leslie are expected to increase over the
next couple of days across the southeastern coast of the United
States, Bermuda, the Bahamas, and the Greater and Lesser Antilles.
These swells will also begin to increase near the coasts of New
England and Atlantic Canada by the end of the week.  Please consult
products from your local weather office as these conditions could
cause life-threatening surf and rip currents.


FORECAST POSITIONS AND MAX WINDS

INIT  03/0900Z 29.6N  56.9W   65 KT  75 MPH
12H  03/1800Z 29.7N  57.0W   65 KT  75 MPH
24H  04/0600Z 30.8N  57.0W   70 KT  80 MPH
36H  04/1800Z 32.8N  57.1W   75 KT  85 MPH
48H  05/0600Z 35.0N  57.3W   70 KT  80 MPH
72H  06/0600Z 37.1N  56.7W   65 KT  75 MPH
96H  07/0600Z 37.0N  53.7W   60 KT  70 MPH
120H  08/0600Z 37.0N  50.5W   55 KT  65 MPH

$$
Forecaster Brown

t02436

今天是編擾第14天，將再度轉向南下...

000
WTNT43 KNHC 070249
TCDAT3

Tropical Storm Leslie Discussion Number  43
NWS National Hurricane Center Miami FL       AL132018
1100 PM AST Sat Oct 06 2018

Leslie's convective organization has changed little since the
previous advisory, with a small burst of deep convection having
developed just southeast of the center. The intensity remains at 50
kt based on an average of current intensity estimates from TAFB and
SAB, which is supported by a partial ASCAT pass that showed several
45-kt surface wind vectors well east of the missed low-level center.

The initial motion estimate is easterly or 095/11 kt. Leslie is
forecast to remain embedded in weak mid-latitude west-northwesterly
flow for the next few days, which should keep the cyclone moving
toward the east-southeast over warmer water. By 72 h and beyond,  a
stronger shortwave trough is forecast to dig to the west of Leslie,
lifting the cyclone out toward the east and northeast. The new NHC
forecast track is similar to, but a slower than, the previous
advisory track, but not as slow as the consensus models.

Leslie is expected to weaken slightly during the next 36 h as the
cyclone entrains some drier air.  After that time, however, Leslie
is expected to move over warmer waters with SSTs reaching more than
25 deg C by 48 h and beyond while the shear is forecast to remain
low. As a result, some modest re-strengthening is forecast on days
2-5. The official intensity forecast closely follows the IVCN
intensity consensus model.

Large swells generated by Leslie are expected to continue during the
next few days across the northeastern coast of the United States,
Bermuda, the Greater and Lesser Antilles, and Atlantic Canada.
Please consult products from your local weather office as these
conditions could cause life-threatening surf and rip currents.

FORECAST POSITIONS AND MAX WINDS

INIT  07/0300Z 37.3N  52.9W   50 KT  60 MPH
12H  07/1200Z 36.8N  51.2W   45 KT  50 MPH
24H  08/0000Z 36.2N  48.8W   45 KT  50 MPH
36H  08/1200Z 35.4N  46.4W   45 KT  50 MPH
48H  09/0000Z 34.2N  43.7W   50 KT  60 MPH
72H  10/0000Z 30.9N  38.5W   55 KT  65 MPH
96H  11/0000Z 28.7N  33.9W   55 KT  65 MPH
120H  12/0000Z 29.5N  28.5W   55 KT  65 MPH

$$
Forecaster Stewart

t02436

持續南下中，將再次達到颶風強度

000
WTNT43 KNHC 091440
TCDAT3

Tropical Storm Leslie Discussion Number  53
NWS National Hurricane Center Miami FL       AL132018
1100 AM AST Tue Oct 09 2018

Recent Dvorak fixes and ASCAT data indicate that Leslie's maximum
winds remain around 55 kt. Although the winds have not yet
increased, the surface center of the tropical storm has become more
embedded within its cold cloud tops and several recent microwave
overpasses indicate that the cyclone is beginning to establish an
inner-core. Strengthening is therefore still expected, and Leslie is
forecast to become a hurricane by tomorrow. The tropical storm is
currently moving south-southeastward at around 11 kt, and the models
are in good agreement that a south-southeastward to southward motion
will continue for the next 24 h or so.

Beginning around 36 h, both the track and intensity forecasts become
very uncertain.  In general, most of the global models and their
ensembles indicate that Leslie will begin to accelerate toward the
east-northeast or northeast by Thursday as a mid-latitude trough
approaches from the northwest, however the timing and extent of the
interaction is still highly variable from model to model. Based on
the GFS and ECMWF ensembles, a range of possibilities exists, from
Leslie essentially merging with this trough and becoming
extratropical over the far northeast Atlantic, to Leslie interacting
with the trough very little and continuing to meander over the
central Atlantic.  There has been a significant change in the
consensus aids to show a slower track for Leslie based on recent
shifts in the deterministic models, but the NHC track forecast has
not been changed nearly as much, out of respect for continuity and
the high uncertainty in the forecast.

The low confidence in the track forecast beyond 36 h affects the
intensity forecast as well, since it is unclear what environment the
storm will be located within.  The intensity forecast is therefore
held near the intensity consensus, and still calls for steady
strengthening during the next several days, followed by weakening by
the end of the forecast period.  If Leslie moves as far east as
shown in the NHC track forecast, it would likely become a post-
tropical low by day 5, as shown explicitly in the forecast. However,
until confidence in the track increases, I can't rule out that
Leslie could remain a tropical cyclone almost indefinitely if it
continues meandering over the northern Atlantic.

FORECAST POSITIONS AND MAX WINDS

INIT  09/1500Z 31.3N  43.5W   55 KT  65 MPH
12H  10/0000Z 29.9N  42.9W   55 KT  65 MPH
24H  10/1200Z 28.5N  42.6W   60 KT  70 MPH
36H  11/0000Z 28.1N  41.7W   65 KT  75 MPH
48H  11/1200Z 28.9N  39.5W   70 KT  80 MPH
72H  12/1200Z 32.0N  31.5W   75 KT  85 MPH
96H  13/1200Z 33.5N  22.0W   65 KT  75 MPH
120H  14/1200Z 33.5N  18.0W   50 KT  60 MPH...POST-TROPICAL

$$
Forecaster Zelinsky

2天後開始加速移向西非，只不過兩大數值目前不認為會很乾脆的一去不復返...

t02436

03Z再次增強為颶風。

000
WTNT43 KNHC 100243
TCDAT3

Hurricane Leslie Discussion Number  55
NWS National Hurricane Center Miami FL       AL132018
1100 PM AST Tue Oct 09 2018

Satellite and microwave data indicate that Leslie has become a
hurricane again, almost exactly a week after it did the first time.
A WindSat pass from earlier today showed the development of an eye
feature, and with the Dvorak estimates from TAFB and SAB at
hurricane strength, the initial wind speed is set to 65 kt.  The
latest GOES-16 proxy visible imagery suggests that a ragged eye has
formed, although the eyewall is open on the southwestern side.

Leslie is atypically intensifying while moving south-southeastward
at 8 kt.  The hurricane should continue to lose latitude for a day
or so then get accelerated east-northeastward by a mid-latitude
trough until Friday.  After that time, there is a ginormous spread
in the model ensembles with Leslie's final destination ranging from
Ireland all the way to missing the trough and turning around to the
southwest due to a building eastern Atlantic subtropical ridge.
Compared to 12 hours ago, more of the ensemble members are showing
Leslie getting left behind, which is also reflected in the latest
deterministic runs as well.  Something tells me that Leslie has at
least one more trick up its sleeve, so the official forecast shows
this trend, but is very low confidence.

With fairly low shear and marginally warm waters for the next day
or two, there is no reason to expect that Leslie won't continue to
intensify.  Model guidance is higher than the last cycle, with the
normally conservative ECMWF and GFS models even suggesting that
Leslie becomes a category 2 hurricane in a couple of days.  Most of
the rest of the guidance is lower than those models, but the
intensity forecast is shaded in the direction of the ECMWF/GFS,
and is higher than the last NHC prediction.  After that time, an
increase in shear and lower SSTs should cause Leslie to weaken. It
is even possible it will become a post-tropical cyclone by day 5,
but I'm not going to show that at this time since I was too
premature last night in this transition.


FORECAST POSITIONS AND MAX WINDS

INIT  10/0300Z 29.5N  42.6W   65 KT  75 MPH
12H  10/1200Z 28.4N  42.3W   70 KT  80 MPH
24H  11/0000Z 28.0N  41.6W   75 KT  85 MPH
36H  11/1200Z 28.6N  39.8W   80 KT  90 MPH
48H  12/0000Z 29.9N  36.4W   80 KT  90 MPH
72H  13/0000Z 32.2N  27.0W   75 KT  85 MPH
96H  14/0000Z 32.0N  21.0W   55 KT  65 MPH
120H  15/0000Z 30.0N  22.0W   40 KT  45 MPH

$$
Forecaster Blake

t02436

快速移動中，明天將以C1強度登陸葡萄牙！

000
WTNT43 KNHC 130237
TCDAT3

Hurricane Leslie Discussion Number  67
NWS National Hurricane Center Miami FL       AL132018
1100 PM AST Fri Oct 12 2018

Although Leslie continues to produce a compact area of deep
convection, microwave data since the previous advisory indicate
that the mid-level center is becoming more separated from the
low-level center due to increasing shear.  Dvorak final-T numbers
have begun to decrease a bit, and the initial intensity is
therefore set at 70 kt.  A cold front is beginning to wrap around
the western side of Leslie's circulation, and the global models
indicate that the cyclone should lose its warm core and become
fully embedded within the frontal zone by 24 hours, if not sooner.
Despite sea surface temperatures of 17-23 degrees Celsius ahead of
Leslie, baroclinic forcing is likely to maintain the system's
intensity as it becomes extratropical.  As a result, Leslie is
forecast to reach the Iberian Peninsula as a hurricane-force
extratropical low, with the NHC intensity forecast most closely
following the GFS guidance.  Rapid weakening is forecast once the
low moves inland, and the system should dissipate over the higher
terrain of Spain in about 48 hours.

The forward motion is east-northeastward, or 075/31 kt.  Located
within the base of a progressive trough, Leslie should maintain
this trajectory, slowing down only a little bit before it reaches
Portugal and Spain in 24-36 hours.  Except for the UKMET model,
which shows Leslie turning more northeastward toward the
northwestern Iberian Peninsula, the rest of the track guidance is
tightly clustered and brings the center inland across central
Portugal and western Spain.  Because most of the models are in good
agreement and are close to the previous official forecast, no
significant changes were made to the NHC forecast on this cycle.

Based on coordination from earlier today, the meteorological
services of Portugal and Spain will handle hazard information for
their respective countries via local weather products.


Key Messages:

1. Leslie is expected to bring near hurricane-force winds to
portions of Portugal late Saturday as a powerful post-tropical
cyclone. Gale-force winds are also likely to affect portions of
western Spain Saturday night and Sunday.

2. Leslie is expected to produce rainfall amounts of 25 to 75 mm (1
to 3 inches) with isolated amounts as high as 100 mm (4 inches)
across portions of Portugal and Spain, which could cause flash
flooding.

3. For more information on Leslie, interests in Portugal should
refer to products from the Portuguese Institute for Sea and
Atmosphere at www.ipma.pt.  Interests in Spain should refer to
products from the State Meteorological Agency at www.aemet.es.


FORECAST POSITIONS AND MAX WINDS

INIT  13/0300Z 34.7N  20.7W   70 KT  80 MPH
12H  13/1200Z 36.5N  15.4W   65 KT  75 MPH
24H  14/0000Z 38.9N   9.4W   65 KT  75 MPH...POST-TROP/EXTRATROP
36H  14/1200Z 41.0N   5.1W   40 KT  45 MPH...POST-TROP/EXTRATROP
48H  15/0000Z 42.3N   1.1W   25 KT  30 MPH...POST-TROP/EXTRATROP
72H  16/0000Z...DISSIPATED

$$
Forecaster Berg

ben811018

很特別的系統
終於(!)找到歸宿