霧峰追風者

  四級颶風  
編號：20 E
名稱：Rosa

  基本資料  
擾動編號日期：2018 年 09 月 24 日 07 時
命名日期　　：2018 年 09 月 25 日 23 時
撤編日期　　：2018 年 00 月 00 日 00 時
登陸地點　　：暫無

  巔峰時期資料  
近中心最強風速 ：125 kt
海平面最低氣壓 ：940 百帕

  過去路徑圖  

  擾動編號資料  
95E.INVEST.20kts-1006mb-13.5N-101.7W


NHC : 50%

1. A broad area of low pressure located a couple of hundred miles
south-southwest of Acapulco, Mexico, is beginning to show signs of
organization.  Environmental conditions are expected to be conducive
for further development and a tropical depression is likely to from
within the next few days while it moves west-northwestward well off
the coast of Mexico.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 5 days...high...90 percent.

以上資料來自：NHC、颱風論壇整理製作

霧峰追風者

NHC 展望提升至90%。

1. Showers and thunderstorms associated with a low pressure system
located around 300 miles south-southwest of Manzanillo, Mexico
continue to show signs of organization.  Environmental conditions
appear conducive for further development, and a tropical depression
is likely to form within the next day or so while the system moves
west-northwestward, well offshore of the coast of Mexico.
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 5 days...high...90 percent.

霧峰追風者

NHC 升格熱帶低壓20E,巔峰上望90節。

831
WTPZ45 KNHC 250843
TCDEP5

Tropical Depression Twenty-E Discussion Number   1
NWS National Hurricane Center Miami FL       EP202018
300 AM MDT Tue Sep 25 2018

The low pressure system that NHC has been monitoring off the coast
of southwestern Mexico has now become a tropical depression, the
twentieth of the eastern North Pacific 2018 season.  ASCAT data from
around 0400 UTC indicated that the system had a well-defined center
and maximum winds in the 25-30 kt range.  In addition, satellite
images show deep convection increasing in coverage and intensity
near the center.  The initial wind speed is set at 30 kt, based on
the ASCAT data, but this is a little below the latest Dvorak
estimate from TAFB.

Since the depression has only recently formed, the initial motion
is an uncertain 280/7 kt.  Mid-level ridging to the north of the
system should keep the depression on a westward to west-
northwestward path at about the same forward speed for the
next few days.  Thereafter, the models show the ridge breaking down
due to a large cut off deep-layer low moving toward the west coast
of the United States.  In response, the cyclone is expected to turn
to the northwest this weekend.  The models agree on this overall
scenario, but there is a fair amount of spread by the end of the
forecast period.  The NHC track forecast lies near the middle of
the guidance envelope and close to the best performing models, the
consensus aids.

The environmental conditions appear favorable for the depression to
strengthen.  SSTs are expected to remain quite warm beneath the
cyclone for the next several days while vertical wind shear values
are around 10 kt or less.  These conditions combined with a
moist airmass should allow for at least steady strengthening during
the next 3 to 4 days.  Some weakening is possible by the end of the
forecast period due to slightly cooler SSTs and an increase in
shear.  The NHC intensity forecast shows a slower rate of
strengthening than the guidance, since the system is still
in the developing stage, but predicts peak winds near the IVCN
consensus model.

FORECAST POSITIONS AND MAX WINDS

INIT  25/0900Z 14.5N 107.2W   30 KT  35 MPH
12H  25/1800Z 14.9N 108.2W   35 KT  40 MPH
24H  26/0600Z 15.5N 109.8W   40 KT  45 MPH
36H  26/1800Z 15.8N 111.2W   55 KT  65 MPH
48H  27/0600Z 16.1N 112.6W   70 KT  80 MPH
72H  28/0600Z 16.9N 115.6W   90 KT 105 MPH
96H  29/0600Z 18.3N 118.1W   90 KT 105 MPH
120H  30/0600Z 20.7N 119.5W   85 KT 100 MPH

$$
Forecaster Cangialosi

霧峰追風者

NHC 15Z命名Rosa，巔峰上望95節。

060
WTPZ45 KNHC 251434
TCDEP5

Tropical Storm Rosa Discussion Number   2
NWS National Hurricane Center Miami FL       EP202018
900 AM MDT Tue Sep 25 2018

The cloud pattern of the tropical cyclone has become better
organized, with developing convective banding features.  Dvorak
intensity estimates are 35 kt and 45 kt from SAB and TAFB,
respectively, and the current intensity estimate is set at 40 kt.
Thus the system is being upgraded to a tropical storm.  Conditions
favor continued strengthening, with Rosa likely to remain in an
environment of warm waters, low shear, and a very moist mid-level
air mass for the next several days.  The official intensity
forecast is a little higher than the previous one, but below some of
the objective guidance.  By late in the forecast period, a gradual
weakening trend should commence as the system begins to move over
slightly cooler waters.

The storm is moving west-northwestward, or 285/8 kt.  A mid-level
ridge is forecast by the global models to remain in place to the
north of Rosa through the middle part of the forecast period.  This
would likely maintain a generally west-northwestward motion for the
next 72 hours or so.  By days 4-5, the ridge is predicted to weaken
which should result in a gradual turn toward the northwest and
north-northwest.  The official track forecast is similar to that
from the previous advisory and is close to the corrected dynamical
model consensus, HCCA.

FORECAST POSITIONS AND MAX WINDS

INIT  25/1500Z 14.7N 108.0W   40 KT  45 MPH
12H  26/0000Z 15.2N 109.1W   50 KT  60 MPH
24H  26/1200Z 15.8N 110.6W   60 KT  70 MPH
36H  27/0000Z 16.1N 112.1W   70 KT  80 MPH
48H  27/1200Z 16.4N 113.7W   80 KT  90 MPH
72H  28/1200Z 17.1N 116.7W   95 KT 110 MPH
96H  29/1200Z 18.8N 118.9W   90 KT 105 MPH
120H  30/1200Z 21.0N 120.0W   85 KT 100 MPH

$$
Forecaster Pasch

t02436

15Z升C1，巔峰上望110節。

892
WTPZ45 KNHC 261438
TCDEP5

Hurricane Rosa Discussion Number   6
NWS National Hurricane Center Miami FL       EP202018
900 AM MDT Wed Sep 26 2018

Rosa is undergoing rapid intensification.  Rosa's inner core has
quickly consolidated, indicated by a 1134 UTC SSMI/S image that
showed a solid mid-level ring with a strong well-developed banding
feature in the south semicircle.  The lower frequency image from
the pass indicated a small break in the north portion, probably due
to the drier air and northeasterly shear that had been inhibiting
the cyclone's cloud pattern last night.  Based on the conventional
and microwave imagery presentation, the initial intensity is raised
to 65 kt.

Rosa should continue on this fast strengthening trend during the
next 12 hours or so.  Afterward, further intensification, at a
slower pace, is expected during the next couple of days.  Through
the remaining portion of the forecast, gradual weakening is expected
as a result of decreasing sea surface temperatures, increasing
southwesterly vertical shear, and an invading stable, more drier,
marine layer air mass.

The initial motion is estimated to be west-northwestward, or 290/9
kt, within the easterly mid-tropospheric flow produced by a
ridge to the north of the hurricane.  Around mid-period, the
large-scale models show a weakness developing the in the
aforementioned ridge in response to a mid-latitude trough
approaching the southwest U.S. and Baja California peninsula.  As a
result of this synoptic pattern change, Rose should move
northwestward Saturday and then north-northwestward Sunday.  The
large along and cross-track spread recognized in the guidance 24
hours ago has decreased significantly, increasing the forecast
confidence some beyond 48 hours.  The NHC forecast is fairly close
to the previous one, and is based primarily on the multi-model
consensus.


FORECAST POSITIONS AND MAX WINDS

INIT  26/1500Z 16.1N 111.4W   65 KT  75 MPH
12H  27/0000Z 16.4N 112.7W   90 KT 105 MPH
24H  27/1200Z 16.6N 114.6W  100 KT 115 MPH
36H  28/0000Z 16.8N 116.2W  105 KT 120 MPH
48H  28/1200Z 17.3N 117.5W  110 KT 125 MPH
72H  29/1200Z 19.2N 119.5W  105 KT 120 MPH
96H  30/1200Z 22.0N 120.2W   85 KT 100 MPH
120H  01/1200Z 24.9N 119.0W   60 KT  70 MPH

$$
Forecaster Roberts

t02436

底層相當扎實

15Z評價90節，即將叩關MH。

697
WTPZ45 KNHC 271454
TCDEP5

Hurricane Rosa Discussion Number  10
NWS National Hurricane Center Miami FL       EP202018
800 AM PDT Thu Sep 27 2018

Rosa is becoming better organized.  Conventional satellite imagery
show a large area of cold cloud tops near the center, and there is
a hint of an eye in the first-light visible images.  Microwave
imagery indicates that the eye structure underneath the overcast
has become better defined, with less evidence of dry air entrainment
than seen yesterday.  The initial intensity has been increased to
90 kt in best agreement with the subjective Dvorak estimate from
TAFB and the CIMSS ADT technique.  The hurricane currently has good
outflow in all directions.

Conditions appear generally favorable for continued strengthening
for the next 24-36 hr, and the new intensity forecast now makes Rosa
a major hurricane in 12 h.  It should be noted that if the current
strengthening is the start of the previously anticipated rapid
intensification Rosa could get stronger than the current forecast,
which shows a peak intensity of 105 kt near the upper edge of the
intensity guidance.  After 36 h, the forecast track takes the
cyclone over decreasing sea surface temperatures, and by the end of
the forecast period it is expected to encounter strong southwesterly
vertical shear.  This combination should cause significant
weakening, and Rosa is expected to be a tropical storm as it
approaches the Baja California peninsula near the end of the
forecast period.

The initial motion is a somewhat uncertain 270/10.  For the next
12-24 h, the hurricane should move generally westward on the south
side of the subtropical ridge over the Pacific west of northern
Mexico and a mid-latitude ridge over California.  Subsequently, Rosa
should turn northwestward and northward through a break in the ridge
caused by a large mid-latitude trough moving eastward through the
northeastern Pacific.  By 96-120 h, Rosa should recurve
northeastward into the westerlies on the eastern side of the trough
and move in the general direction of northwestern Mexico and the
northern Baja California peninsula.  There remains some spread in
the guidance forward speed after recurvature, with the GFS being
faster than the ECMWF.  The new intensity forecast is a blend of
these extremes in forward speed at the 96 and 120 h points.
Overall, the guidance envelope has shifted a little west since the
previous advisory, and the new track is also shifted a little
westward.

FORECAST POSITIONS AND MAX WINDS

INIT  27/1500Z 17.2N 115.4W   90 KT 105 MPH
12H  28/0000Z 17.3N 116.9W  100 KT 115 MPH
24H  28/1200Z 17.5N 118.1W  105 KT 120 MPH
36H  29/0000Z 18.3N 119.0W  105 KT 120 MPH
48H  29/1200Z 19.5N 119.4W  100 KT 115 MPH
72H  30/1200Z 22.5N 119.5W   80 KT  90 MPH
96H  01/1200Z 26.0N 118.0W   60 KT  70 MPH
120H  02/1200Z 29.5N 115.5W   40 KT  45 MPH

$$
Forecaster Beven

霧峰追風者

風眼開啟清空，00Z 強度直升四級颶風。

t02436

09Z持續評價125節，將在今天達到顛峰！

692
WTPZ45 KNHC 280838
TCDEP5

Hurricane Rosa Discussion Number  13
NWS National Hurricane Center Miami FL       EP202018
200 AM PDT Fri Sep 28 2018

Although enhanced BD-curve infrared imagery shows that Rosa's 20 n
mi wide eye has continued to warm (+16C) this morning, the southwest
quadrant of the eyewall appears to have weakened, or collapsed, and
the inner ring cloud tops have warmed considerably.  This change in
the cloud pattern maybe the early stage of an eyewall replacement
cycle (ERC).  It's certainly worth noting, however, that the
satellite presentation about 3 hours ago indicated that Rosa may
have reached a peak intensity of 130-135 kt which was also
indicated in the ADT adjusted raw T-numbers.  For this advisory,
the initial intensity is set at 125 kt and is based on a compromise
of the subjective and objective satellite intensity estimates.

Rosa has a small window of opportunity to complete its ERC and
restrengthen before it encounters decreasing oceanic temperatures,
and increasing southwesterly shear.  These inhibiting factors, along
with Rosa moving into a more stable air mass, should cause a
downward intensity trend by early next week, and for the cyclone to
weaken to a tropical storm by Tuesday, and a tropical depression as
it quickly moves northeastward over the southwestern U.S.  The
intensity forecast is similar to my predecessor's and is close to
the IVCN consensus through 48 hours, then quite similar to the
NOAA-HCCA intensity model beyond that forecast period.

The initial motion is estimated to be westward, or 270/6 kt.  A
mid-level ridge over the southwestern United States is forecast to
weaken over the next couple of days in response to an approaching
mid-level shortwave trough from the northwest.  This growing
weakness in the ridge should influence Rosa to gradually turn
northward through mid-period, and afterward, turn northeastward
within the strong mid- to upper tropospheric southwesterly flow
produced by the aforementioned trough.  The NHC track forecast was
adjusted ever so slightly to the left of the previous one to light
more closely to the TVCN and HCCA multi-model guidance.

FORECAST POSITIONS AND MAX WINDS

INIT  28/0900Z 16.9N 117.3W  125 KT 145 MPH
12H  28/1800Z 17.4N 117.9W  130 KT 150 MPH
24H  29/0600Z 18.4N 118.4W  120 KT 140 MPH
36H  29/1800Z 20.1N 118.8W  100 KT 115 MPH
48H  30/0600Z 22.0N 118.8W   85 KT 100 MPH
72H  01/0600Z 25.9N 117.6W   65 KT  75 MPH
96H  02/0600Z 30.6N 115.0W   40 KT  45 MPH...INLAND
120H  03/0600Z 38.2N 109.4W   25 KT  30 MPH...POST-TROP/INLAND

$$
Forecaster Roberts