t02436

即將在兩天之後正面襲擊夏威夷，飛機實測現正進行中。
五天之後以40節越過西經170度，至於是否能以熱帶風暴強度進入西太本周末再觀察。

Hurricane Olivia Discussion Number  40
NWS Central Pacific Hurricane Center Honolulu HI   EP172018
500 AM HST Mon Sep 10 2018

Olivia's eye has been appearing at times this morning. The outflow
pattern remains impressive, so it does not appear to be negatively
impacted by vertical wind shear of around 10 kt. The satellite fix
agencies (JTWC, SAB, and PHFO) provided unanimous subjective Dvorak
current intensity estimates of 4.5/77 kt. The UW-CIMSS ADT estimate
was 4.2/70 kt. Based on all of this information, we are maintaining
the initial intensity at 75 kt for this advisory. Note that an
aircraft flown by the U.S. Air Force Reserves 53rd Weather
Reconnaissance Squadron is scheduled to sample the inner core and
outer wind field of Olivia starting in a few hours. This will
give us a much better idea of the latest intensity of Olivia once
they arrive.

Olivia continues to move nearly due west with a current motion of
270/9 kt. This motion is being induced by a deep layer ridge to the
north and northwest of the tropical cyclone. During the next 12
hours or so, the ridge is expected to strengthen and build southward
ahead of Olivia, forcing the tropical cyclone to shift toward a
west-southwest track. This motion is expected to continue through
day 3. The track guidance appears have slightly more spread through
72 hours, especially from 36 to 72 hours. The spread is even greater
during days 4 and 5. The current forecast track is very close to the
previous, except it has been nudged to the right and is slightly
slower during the first 72 hours. Little change has been made in the
day 4 and 5 positions. This closely follows the latest TVCE, FSSE,
GFEX and HCCA guidance. Again, since the is a wider spread in the
track guidance, we want to emphasize the uncertainty in our track
forecast. It is important to NOT focus on the exact forecast track
of Olivia's center across the islands. A slight deviation to the
right or left can bring vastly different weather hazards to any
islands that are directly impacted by this potentially damaging
tropical cyclone.

Vertical wind shear remains relatively weak in the vicinity of
Olivia. Water temperatures, as well as ocean heat content values,
are expected to increase along the forecast track. Therefore, Olivia
will likely remain a hurricane through 36 hours. After that,
increasing vertical wind shear is forecast to take its toll on
Olivia, so that it may be a strong tropical storm within 48 hours.
Additional slow weakening is expected to persist during days 3
through 5. The latest forecast is close to the IVCN and CTCI. Note
that based on the latest track and intensity along with the wind
speed probabilities, Tropical Storm Warnings have been issued for
the Big Island of Hawaii and the islands of Maui County.

KEY MESSAGES:

1.  It is important to not focus on the exact forecast track and
intensity when planning for Olivia. Persons on the main Hawaiian
Islands east of Kauai should continue preparing for the likelihood
of direct impacts from this system today and early Tuesday. Those
impacts could include intense flooding rainfall, damaging winds,
large and dangerous surf, and storm surge.

2.  Regardless of the exact track and intensity that Olivia takes
as it approaches the islands, significant effects often extend far
from the center. In particular, the mountainous terrain of Hawaii
can produce localized areas of strongly enhanced winds and
rainfall, even well away from the tropical cyclone center.


FORECAST POSITIONS AND MAX WINDS

INIT  10/1500Z 21.7N 148.0W   75 KT  85 MPH
12H  11/0000Z 21.7N 149.3W   75 KT  85 MPH
24H  11/1200Z 21.4N 151.3W   75 KT  85 MPH
36H  12/0000Z 21.1N 153.4W   65 KT  75 MPH
48H  12/1200Z 20.7N 155.7W   60 KT  70 MPH
72H  13/1200Z 19.9N 160.7W   45 KT  50 MPH
96H  14/1200Z 20.0N 166.0W   40 KT  45 MPH
120H  15/1200Z 21.0N 171.0W   40 KT  45 MPH

$$
Forecaster Houston

霧峰追風者

70節強度正式進入中太，CPHC 開始發報。

WTPA45 PHFO 090302
TCDCP5

Hurricane Olivia Discussion Number  34
NWS Central Pacific Hurricane Center Honolulu HI   EP172018
500 PM HST Sat Sep 08 2018

Olivia lost its well-defined center feature in conventional
satellite imagery late this afternoon and now appears as a rather
messy asymmetric blob of deep convection. However, SSMI and GMI
overpasses at 2349 and 2336 UTC, respectively, showed an eyewall
remained, except for a break on the west side, along with a very
well organized low level circulation. The satellite intensity
estimates showed some spread, with 4.5 from PHFO and UW-CIMSS ADT,
4.0 from TAFB and SAB, 3.5 from JTWC. The current intensity was
lowered to 70 kt based on a blend of these estimates, and
considering the degradation seen in the satellite imagery over the
last few hours.

The initial motion estimate is 280/14. Olivia is moving just north
of due west, to the south of strong deep layer ridging to the west
through north of the tropical cyclone. Little change is
anticipitated for the first 48 hours or so as this ridging builds
westward in tandem with Olivia. After 48 hours, the portion of the
ridge to the west of Olivia is forecast to strengthen, shunting the
tropical cyclone on a more west-southwest motion. The track
guidance remains fairly tightly clustered, and this forecast is very
similar to the previous forecast track, which brings the center of
Olivia over the main Hawaiian Islands between 72 and 96 hours. A
more westward motion is expected to resume after Olivia's passage
through the islands, as the upper ridge retreats westward and the
circulation center becomes increasingly steered by the lower level
trades.

Olivia is in a very weak shear environment, but moving over
marginal sea surface temperatures of 25.5C. The hurricane has
already traversed the coolest water it was going to encounter, but
SSTs stay sub-27C until Olivia gets close to the islands. This
should allow Olivia to only very slowly weaken or maintain intensity
through the next 24 to 48 hours. Shear should begin to gradually
increase over Olivia after 48 hours, leading to a slow weakening
trend, but likely not soon enough to prevent some significant
impacts to the main Hawaiian Islands.


KEY MESSAGES:

1.  It is important to recognize that errors in both forecast track
and intensity, particularly at longer time ranges, can be large.
While it is too soon to determine the location and magnitude of the
worst impacts, all interests in Hawaii should continue to monitor
the progress of Olivia, and use this time to prepare for the
increasing liklihood of direct impacts from this system.

2.  Regardless of the exact track and intensity that Olivia takes
as it approaches the islands, significant effects often do extend
far from the center. In particular, the mountainous terrain of
Hawaii can produce localized areas of strongly enhanced winds and
rainfall, even well away from the tropical cyclone center.


FORECAST POSITIONS AND MAX WINDS

INIT  09/0300Z 21.8N 140.8W   70 KT  80 MPH
12H  09/1200Z 22.0N 142.9W   70 KT  80 MPH
24H  10/0000Z 22.1N 145.3W   70 KT  80 MPH
36H  10/1200Z 22.1N 147.5W   65 KT  75 MPH
48H  11/0000Z 22.0N 149.4W   65 KT  75 MPH
72H  12/0000Z 21.2N 153.5W   55 KT  65 MPH
96H  13/0000Z 20.1N 158.4W   50 KT  60 MPH
120H  14/0000Z 19.5N 163.5W   40 KT  45 MPH

$$
Forecaster R Ballard

t02436

即將在明天進入中太，五天後以TS強度正面影響夏威夷。

224
WTPZ42 KNHC 080256
TCDEP2

Hurricane Olivia Discussion Number  30
NWS National Hurricane Center Miami FL       EP172018
800 PM PDT Fri Sep 07 2018

The cloud pattern of Olivia has continued to degrade this evening
with warming of the inner core, and a decreasing eye temperature. A
compromise of the Dvorak satellite intensity estimates, and an
earlier SATCON analysis, support decreasing the initial wind speed
to 85 kt.  Olivia still has an annular appearance with the cloud
pattern consisting of an inner core with little to no outer bands.

Continued slow weakening is forecast during the next 3 days as
Olivia moves over marginal sea surface temperatures of about 25C and
into an increasingly drier, more stable thermodynamic environment.
Afterward, Olivia will move back over slightly warmer waters and
remain in a low shear environment, so little change in strength is
expected through day 3. Through the remaining portion of the
forecast, southwesterly vertical wind shear of 15-20 kt should
induce more significant weakening.

Olivia's motion is estimated to be west-northwestward, or 290/13 kt,
and is being steered by a strong deep-layer subtropical ridge that
extends from Mexico and the southwestern U.S. westward into the
central Pacific.  The cyclone is forecast to move west-northwestward
for 72 hours or so before turning to the west, or even
west-southwest, as the aforementioned ridge builds to the north. The
official forecast has been adjusted south of the previous forecast
beyond day 3 to conform more with the NOAA-HCCA and TVCN consensus
models.  On the forecast track, Olivia is expected to cross into the
central Pacific basin by late Saturday and approach the Hawaiian
Islands in 4 to 5 days.

KEY MESSAGES

1. Olivia is forecast to approach the main Hawaiian Islands from
the east early next week, but it is too soon to determine the exact
location and magnitude of any impacts.  Interests in Hawaii should
monitor the progress of Olivia this weekend and use this time to
enact your hurricane action plan.

2.  Do not focus on the exact track or intensity forecast, or any
specific landfall location, as errors can be large at extended time
ranges. Tropical storm or hurricane conditions could be felt
anywhere in the islands as significant impacts could extend well
away from the center.


FORECAST POSITIONS AND MAX WINDS

INIT  08/0300Z 20.9N 135.2W   85 KT 100 MPH
12H  08/1200Z 21.3N 137.3W   80 KT  90 MPH
24H  09/0000Z 21.6N 140.0W   75 KT  85 MPH
36H  09/1200Z 21.8N 142.6W   70 KT  80 MPH
48H  10/0000Z 21.8N 145.0W   65 KT  75 MPH
72H  11/0000Z 21.7N 149.0W   65 KT  75 MPH
96H  12/0000Z 20.9N 152.8W   55 KT  65 MPH
120H  13/0000Z 19.5N 157.3W   45 KT  50 MPH

$$
Forecaster Roberts/Birchard

霧峰追風者

風眼清空，NHC 強度升四級颶風。

345
WTPZ42 KNHC 070232
TCDEP2

Hurricane Olivia Discussion Number  26
NWS National Hurricane Center Miami FL       EP172018
800 PM PDT Thu Sep 06 2018

Olivia's satellite presentation is an outstanding example of an
annular hurricane with the shape of a truck tire.  In fact, the
Annular Hurricane Index on the SHIPS model output is 100. The
hurricane has a distinct clear eye surrounded by a ring of very deep
convection. The Dvorak numbers, both objective and subjective, are
T6.0, and on this basis, the winds are increased to 115 kt in this
advisory. The current annular pattern indicates that hurricane
should weaken more slowly that indicated by guidance in the short
term. Nevertheless, since the ocean is a little bit cooler along the
forecast track, very gradual weakening is forecast through the next
5 days. The confidence in the intensity forecast is not very high.

On the contrary, the confidence in the track forecast is high.
Olivia is fully embedded within the easterly flow south of a
subtropical high, and the hurricane is moving toward the
west-northwest or 290 degrees at 12 kt. The subtropical high will
persist, and most likely expand farther westward, and this flow
pattern will force Olivia to move on the general westward track or
even south of due west by the end of the forecast period. Guidance
for the next 5 days is in extremely good agreement, and the NHC
forecast in on top of the skinny guidance envelope.

FORECAST POSITIONS AND MAX WINDS

INIT  07/0300Z 19.1N 129.7W  115 KT 130 MPH
12H  07/1200Z 19.7N 131.6W  115 KT 130 MPH
24H  08/0000Z 20.5N 134.2W  100 KT 115 MPH
36H  08/1200Z 21.2N 136.8W   90 KT 105 MPH
48H  09/0000Z 21.5N 139.5W   85 KT 100 MPH
72H  10/0000Z 21.8N 144.5W   75 KT  85 MPH
96H  11/0000Z 22.0N 148.5W   70 KT  80 MPH
120H  12/0000Z 21.5N 152.5W   65 KT  75 MPH

$$
Forecaster Avila

t02436

03Z評價110節達到巔峰，09Z已經減弱為100節。

ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM

Hurricane Olivia Discussion Number  17
NWS National Hurricane Center Miami FL       EP172018
800 PM PDT Tue Sep 04 2018

Olivia is displaying a well-defined eye this evening embedded within
a circular central dense overcast.  The rapid intensification seems
to have leveled off, since Dvorak estimates have increased only
slightly, but still support a higher wind speed of 110 kt.

Moderate easterly shear, gradually decreasing sea surface
temperatures, and dry air aloft along the forecast track of Olivia
will likely cause the hurricane to slowly weaken by late Wednesday.
The new intensity forecast is slightly higher than the last one,
near or a bit above the model consensus.  The forecast is on the
higher side of the guidance because I don't feel particularly
confident about this weakening, given the poor performance of the
guidance for this hurricane so far.

Olivia is moving a little south of due west, 265/10.  A
building subtropical ridge over the eastern Pacific is forecast
to cause the hurricane to move westward and west-northwestward
with increasing forward speed during the next several days.
Near the end of the forecast, model guidance is showing a stronger
ridge, and a westward turn is possible.  The guidance envelope has
shifted southward on this cycle, and the official NHC prediction is
adjusted in that direction.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0300Z 16.7N 120.1W  110 KT 125 MPH
12H  05/1200Z 16.9N 121.7W  110 KT 125 MPH
24H  06/0000Z 17.5N 124.2W  105 KT 120 MPH
36H  06/1200Z 18.2N 126.8W  100 KT 115 MPH
48H  07/0000Z 19.1N 129.7W   90 KT 105 MPH
72H  08/0000Z 20.9N 135.2W   75 KT  85 MPH
96H  09/0000Z 22.0N 140.5W   65 KT  75 MPH
120H  10/0000Z 22.5N 145.5W   60 KT  70 MPH

$$
Forecaster Blake

NNNN

t02436

底層圍好了，已經評價90節，NHC保守上望100節。

233
WTPZ42 KNHC 041440
TCDEP2

Hurricane Olivia Discussion Number  15
NWS National Hurricane Center Miami FL       EP172018
800 AM PDT Tue Sep 04 2018

Olivia has become better organized since the last advisory, with
conventional satellite imagery indicating the formation of a 25 n
mi wide eye and a surrounding cold ring of cloud tops in the
eyewall.  Satellite intensity estimates from TAFB and SAB have
increased to 90 kt, and that will be the initial intensity for this
advisory.  This burst of rapid intensification has occurred even
though the analyzed easterly shear in the SHIPS model and analyses
from CIMSS is in the 15-20 kt range.

How much additional intensification will occur is uncertain.  The
intensity guidance suggests that continued shear and decreasing sea
surface temperatures along the forecast track will allow only about
12 h of additional strengthening, and most of the guidance forecasts
only modest strengthening during this time.  However, it is unlikely
that the current rapid intensification will stop that quickly.
Based on this, the new intensity forecast calls for a peak intensity
of 100 kt in 12 h at the upper edge of the intensity guidance, and
it is possible Olivia could get stronger.  After 24 h, the cooler
sea surface temperatures and entrainment of dry air should cause a
gradual weakening even though the shear is forecast to decrease.

The initial motion remains 275/10.  As noted previously, a
building subtropical ridge over the eastern Pacific is forecast
to induce a westward and west-northwestward motion with increasing
forward speed during the next several days.  The model guidance
supports this scenario with a tight clustering, and the new NHC
track forecast is again an update of the previous forecast.


FORECAST POSITIONS AND MAX WINDS

INIT  04/1500Z 17.0N 118.2W   90 KT 105 MPH
12H  05/0000Z 17.2N 119.9W  100 KT 115 MPH
24H  05/1200Z 17.4N 122.1W  100 KT 115 MPH
36H  06/0000Z 18.0N 124.5W   95 KT 110 MPH
48H  06/1200Z 18.8N 127.2W   85 KT 100 MPH
72H  07/1200Z 20.5N 133.0W   75 KT  85 MPH
96H  08/1200Z 22.0N 138.5W   60 KT  70 MPH
120H  09/1200Z 23.0N 143.5W   50 KT  60 MPH

$$
Forecaster Beven

t02436

09Z已命名Olivia，巔峰上望85節。

837
WTPZ42 KNHC 020851
TCDEP2

Tropical Storm Olivia Discussion Number   6
NWS National Hurricane Center Miami FL       EP172018
300 AM MDT Sun Sep 02 2018

The tropical cyclone's convection is still not well organized, and
the cloud pattern consists of an irregularly shaped CDO-like
feature with limited banding.  Nonetheless, a couple of
scatterometer overpasses showed that the cyclone had winds to around
40 kt over the southern semicircle of the circulation.  Therefore
the system is being named, and the aforementioned wind speed will be
used for the advisory intensity.  The north-northeasterly shear
that has been affecting the storm is expected to abate somewhat,
which would allow for further strengthening.  The official
intensity forecast is in line with the latest numerical model
consensus, IVCN.  Some of the models show more rapid strengthening
during the next day or two, but this does not seem likely at this
time since the system is still not very well organized and some
shear is expected to continue affecting it.

The center was somewhat elongated in the scatterometer data, but
appeared to be located a little north of the previous working best
track.  The initial motion is a rather uncertain 300/8 kt.  A weak
mid-level ridge to the north of Olivia should lead to a slow
west-northwestward to northwestward motion over the next day or two.
Thereafter, a strengthening ridge is likely to cause a turn toward
the west with some increase in forward speed.  Late in the forecast
period, the dynamical model consensus indicates a turn back to the
west-northwest.  The official track forecast is a little north of
the previous one, mainly due to the recent re-positioning of the
center.

FORECAST POSITIONS AND MAX WINDS

INIT  02/0900Z 16.0N 112.2W   40 KT  45 MPH
12H  02/1800Z 16.6N 112.7W   45 KT  50 MPH
24H  03/0600Z 17.2N 113.6W   50 KT  60 MPH
36H  03/1800Z 17.5N 114.8W   60 KT  70 MPH
48H  04/0600Z 17.6N 116.6W   70 KT  80 MPH
72H  05/0600Z 17.7N 120.2W   85 KT 100 MPH
96H  06/0600Z 19.0N 124.5W   85 KT 100 MPH
120H  07/0600Z 20.5N 130.0W   75 KT  85 MPH

$$
Forecaster Pasch

t02436

升格17E，暫時上望95節。

410
WTPZ42 KNHC 010234
TCDEP2

Tropical Depression Seventeen-E Discussion Number   1
NWS National Hurricane Center Miami FL       EP172018
900 PM MDT Fri Aug 31 2018

Satellite images indicate that the low pressure system located a
little more than 400 miles southwest of Manzanillo, Mexico, has
developed organized deep convection and a well-defined center.
Therefore, the system now qualifies as a tropical depression, the
seventeenth one of the busy 2018 eastern North Pacific hurricane
season.  The center of the system is estimated to be near the
northeastern portion of the deep convection based on recent
microwave data.  The initial intensity is set at 30 kt, in agreement
with a Dvorak classification from TAFB.

The initial motion of the depression is highly uncertain since it
only recently formed, but my best guess is 285/9.  The system is
expected to move a little slower to the west-northwest or northwest
during the next couple of days while it remains to the south of a
weakness in the subtropical ridge.  Beyond that time, the
subtropical ridge is expected to build to the north of the tropical
cyclone, and that should cause it to turn more westward and increase
in forward speed.  The models agree on this overall scenario, but
there is a fair amount of cross-track (north-south) spread.  The NHC
track forecast lies close to the middle of the guidance envelope
near the various consensus models.

The depression is currently experiencing some northeasterly shear,
and that should limit the strengthening process overnight.  However,
the models show the upper-level pattern becoming quite favorable
this weekend.  The expected decrease in shear combined with warm
SSTs and a moist environment should allow the system to steadily
strengthen for most of the forecast period. The NHC intensity
forecast is a little lower than the HCCA model in the short term,
but leans heavily on that guidance from 48 hours and beyond.  It
should also be noted that the GFS, UKMET, and ECMWF models all show
this system deepening significantly during the next several days,
which is a good indication that this cyclone will likely become
another significant hurricane.

FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 14.3N 108.4W   30 KT  35 MPH
12H  01/1200Z 15.0N 109.5W   30 KT  35 MPH
24H  02/0000Z 15.6N 110.5W   40 KT  45 MPH
36H  02/1200Z 16.1N 111.5W   45 KT  50 MPH
48H  03/0000Z 16.6N 112.7W   60 KT  70 MPH
72H  04/0000Z 17.0N 115.0W   75 KT  85 MPH
96H  05/0000Z 17.4N 118.3W   85 KT 100 MPH
120H  06/0000Z 18.3N 122.6W   95 KT 110 MPH

$$
Forecaster Cangialosi