0908morakot

  四級颶風  
編號：11 L
名稱：Joaquin


  基本資料  
擾動編號日期：2015 年 09 月 26 日 08 時
命名日期　　：2015 年 09 月 29 日 11 時
消散日期　　：2015 年 10 月 09 日 01 時
登陸地點　　：無

  巔峰時期資料  
近中心最強風速 ：135  kt ( CAT.4 )
海平面最低氣壓 ：933 百帕

  過去路徑圖  


  討論帖圖片  
98L.INVEST.20kts.1011mb.24.5N.68.5W


NHC:10%

2. Disorganized showers and a few thunderstorms over the western
Atlantic Ocean several hundred miles south-southwest of Bermuda are
associated with an upper-level low and a surface trough.
Development, if any, of this system is expected to be slow to occur
while it drifts toward the north.  Upper-level winds are forecast to
become unfavorable for development after the weekend.
* Formation chance through 48 hours...low...10 percent
* Formation chance through 5 days...low...10 percent

以上資料來自：NHC、颱風論壇整理製作

t02436

NHC 03Z升格11L
目前預測將不會獲得命名

000
WTNT41 KNHC 280239
TCDAT1

TROPICAL DEPRESSION ELEVEN DISCUSSION NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM AST SUN SEP 27 2015

Late-afternoon visible satellite imagery indicates that the
circulation of the low pressure area located midway between the
Bahamas and Bermuda has become well defined.  Since the low has
already had persistent and organized deep convection, the system is
being declared a tropical depression.  A 2312 UTC SSMI/S overpass
indicated that the center of the depression has become at least
partially exposed to the northwest of a large convective mass due to
moderate northwesterly shear.  The initial wind speed is set to 30
kt, based on a T2.0/30 kt classification from TAFB.  The depression
is expected to be blasted by strong north-northwesterly or northerly
winds associated with the tail of an upper-level trough over the
central Atlantic beginning on Monday.  In fact, global models show
the shear being sufficiently strong enough to result in the cyclone
either becoming a remnant low or dissipating within a few days.  The
intensity forecast is below the multi-model consensus through the
forecast period, closest to the HWRF solution.

A low- to mid- level ridge north and northeast of the cyclone is
steering the lower half of the depression's circulation
northwestward while increasing northwesterly winds aloft are
opposing this motion.  The net deep-layer mean flow is therefore
providing for only a slow northwestward motion of 315/02 kt, a
rather uncertain estimate considering the scatter of recent fixes.
This synoptic pattern is expected to persist for the next couple of
days, resulting in a the cyclone's drifting west-northwestward or
northwestward.  The low- to mid-level ridge is forecast to shift
eastward in 2-3 days as a trough reaches the eastern seaboard of the
United States, and the increasingly shallow system should turn
northwestward and north-northwestward at a faster forward speed if
it still exists.  The track forecast is close to a blend of the GFS
and ECMWF model solutions.

FORECAST POSITIONS AND MAX WINDS

INIT  28/0300Z 27.5N  68.7W   30 KT  35 MPH
12H  28/1200Z 27.7N  69.4W   30 KT  35 MPH
24H  29/0000Z 27.9N  69.9W   30 KT  35 MPH
36H  29/1200Z 28.2N  70.4W   30 KT  35 MPH
48H  30/0000Z 28.8N  70.8W   30 KT  35 MPH
72H  01/0000Z 31.0N  71.6W   30 KT  35 MPH
96H  02/0000Z...DISSIPATED

$$
Forecaster Kimberlain

t02436

NHC 命名Joaquin
一改之前不看好的預報
現在預測能以55節風力影響美東地區

000
WTNT41 KNHC 290237
TCDAT1

TROPICAL STORM JOAQUIN DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM EDT MON SEP 28 2015

Satellite images indicate that the shower and thunderstorm activity
associated with the depression has increased and become better
organized during the past several hours.  In addition, the low-level
center now appears to have moved closer to the convection than it
was earlier. The latest Dvorak classifications from TAFB and SAB
were 2.5/35 kt, and the initial intensity is set at that value,
making the cyclone Tropical Storm Joaquin.  This intensity analysis
also agrees with the reconnaissance aircraft data from earlier today
that showed winds just under tropical-storm force.

The center of Joaquin has been moving southwestward during the last
several hours, but it is expected to begin moving slowly westward
overnight.  This westward track is forecast to continue for a couple
of days while a mid-level ridge remains to the north of the storm.
After that time, a trough is anticipated to amplify over the eastern
United States, which should cause Joaquin to turn northward and
accelerate.  There is considerable spread in the models, mainly due
to the timing of when and how fast the storm makes the northward
turn, due to differences in the evolution of the trough.  In
general, the guidance envelope has shifted southward for the first
couple of days and then westward after that time.  The official
track forecast has been adjusted accordingly, but additional
southward and westward adjustment may be needed in subsequent
advisories.

Northwesterly shear of about 20 kt is currently affecting Joaquin,
causing most of the thunderstorm activity to be located to the
southeast of the center.  The shear is expected to lessen some
during the next couple of days, which in combination with warm water
and high relative humidity values should allow Joaquin to
strengthen.  The official intensity forecast is raised from the
previous one, but is lower than the intensity model consensus at
days 3-5.

FORECAST POSITIONS AND MAX WINDS

INIT  29/0300Z 26.7N  70.4W   35 KT  40 MPH
12H  29/1200Z 26.9N  71.0W   40 KT  45 MPH
24H  30/0000Z 27.1N  72.0W   40 KT  45 MPH
36H  30/1200Z 27.2N  72.8W   45 KT  50 MPH
48H  01/0000Z 27.4N  73.4W   50 KT  60 MPH
72H  02/0000Z 28.6N  74.0W   55 KT  65 MPH
96H  03/0000Z 32.4N  74.0W   55 KT  65 MPH
120H  04/0000Z 38.0N  74.0W   55 KT  65 MPH

$$
Forecaster Cangialosi

t02436

底層風眼構建完成，高層風眼逐漸開啟
NHC 根據稍早飛機實測結果評價70節，15Z正報巔峰上望100節
目前預測五天後將以75節左右強度襲擊美東地區
下一次的實測作業即將在稍晚啟動。

000
WTNT41 KNHC 301458
TCDAT1

HURRICANE JOAQUIN DISCUSSION NUMBER  11
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 AM EDT WED SEP 30 2015

Joaquin has continued to strengthen overnight.  Satellite imagery
shows that the convection has become more symmetric, and recent
visible images show what might be an eye trying to form. An Air
Force Reserve Hurricane Hunter aircraft reported 700-mb flight-
level winds of 83 kt and estimated 70 kt surface winds from the
Stepped Frequency Microwave Radiometer, with a central pressure of
971 mb estimated from the aircraft data.  Based on these, the
initial intensity is increased to 70 kt.

Joaquin has moved a little south of the previous track with an
initial motion of 230/5.  The shortwave ridge causing this motion
is expected to weaken during the next 24-48 hours as a strong
deep-layer trough develops over the southeastern United States.
This is expected to cause the hurricane to turn northward by 72
hours.  There is disagreement in the track guidance between the
ECMWF and the other dynamical models.  The majority of the guidance
forecasts Joaquin to turn west of north after 48-72 hours, with the
storm moving inland over the mid-Atlantic states and merging with
the trough. On the other hand, the ECMWF forecast the hurricane to
move out to sea between North America and Bermuda.  The ECMWF
forecasts Joaquin to move more to the south during the first 24-48
hours than the other models.  In addition, it shows the hurricane
interacting with an upper-level low to its northeast that results in
a more eastward motion after 48 hours.  The new forecast track,
which is similar to the previous track, leans more toward the
non-ECMWF guidance.  However, out of deference to the ECMWF, it
lies to the east of the center of the guidance envelope and the
consensus models. The NOAA G-IV jet is scheduled to fly a synoptic
surveillance mission this afternoon, which, along with special
rawinsonde launches over the eastern U. S., hopefully will reduce
the spread of the guidance.

Joaquin is expected to remain in an environment of moderate
northeasterly vertical shear for the next 24-36 hours.  However,
since it has been steadily strengthening in such an environment,
there is no obvious reason to think it will stop doing so.  After
36 hours, the hurricane is likely to move into an area of divergent
southerly upper-level winds associated with the eastern U. S.
trough.  While there is uncertainty as to how much shear should
occur, it is expected that additional intensification could occur
through 72 hours.  Based on this, the intensity forecast calls for
Joaquin to peak as a major hurricane in about 72 hours, and it is
possible it could be stronger than currently forecast.  After 72
hours, increasing shear and cold air intrusion should cause
weakening and the start of extratropical transition.


KEY MESSAGES:

1. Confidence in the details of the track forecast late in the
period remains low, since the environmental steering currents are
complex and the model guidance is inconsistent.  A wide range of
outcomes is possible, from a direct impact of a major hurricane
along the U.S. east coast to a track of Joaquin out to sea away from
the coast.  It is therefore way too soon to talk about specific
wind, rain, or surge impacts from Joaquin in the U.S.

2. Should the threat to the U.S. increase, any further adjustments
of the forecast to the west would likely be accompanied by an
increase in the forecast forward speed, with impacts along the coast
occurring sooner than currently forecast. A hurricane watch could
be required for portions of the U.S. coast as early as Thursday
evening.

3. Many areas of the eastern U.S. are currently experiencing heavy
rains and gusty winds associated with a frontal system.  This
inclement weather is expected to continue over the next few days,
which could complicate preparations for Joaquin should it head
toward the coast.


FORECAST POSITIONS AND MAX WINDS

INIT  30/1500Z 24.7N  72.6W   70 KT  80 MPH
12H  01/0000Z 24.3N  73.2W   80 KT  90 MPH
24H  01/1200Z 24.1N  74.0W   85 KT 100 MPH
36H  02/0000Z 24.4N  74.4W   90 KT 105 MPH
48H  02/1200Z 25.3N  74.5W   95 KT 110 MPH
72H  03/1200Z 28.5N  73.5W  100 KT 115 MPH
96H  04/1200Z 34.0N  73.0W   90 KT 105 MPH
120H  05/1200Z 38.5N  74.0W   75 KT  85 MPH

$$
Forecaster Beven

t02436

NHC03Z評價100節，巔峰上望C4 120節。

000
WTNT41 KNHC 010250
TCDAT1

HURRICANE JOAQUIN DISCUSSION NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM EDT WED SEP 30 2015

Joaquin has rapidly intensified during the past 24 hours with the
satellite presentation continuing to improve this evening.  The eye
has recently become apparent near the center of the very symmetric
central dense overcast.  An Air Force Reserve Hurricane Hunter
aircraft that has been investigating the hurricane this evening has
measured peak 700 mb flight-level winds of 113 kt and 102 kt surface
winds from the SFMR.  These data support an initial intensity of
100 kt, making Joaquin the second major hurricane of the 2015
Atlantic hurricane season. NOTE: Communications problems have
delayed the public release of the Air Force reconnaissance data.

Joaquin continues to move slowly southwestward with an initial
motion estimate of 220/5 kt.  The hurricane is forecast to move
slowly southwestward or west-southwestward for another 24 hours or
so while it remains to the south of a narrow northeast to southwest
oriented ridge.  This ridge is expected to weaken by Friday as a
trough deepens and cuts off over the southeastern United States.
This should cause Joaquin to turn northward within 48 hours. The 18Z
runs of the GFS and HWRF remain in general agreement with the 12Z
UKMET and Canadian models moving Joaquin around the northeastern
portion of the cut-off low and bring the hurricane inland over the
Carolinas or mid-Atlantic states.  The 12Z ECMWF remains the outlier
by showing a track toward the northeast out to sea.  The NHC
forecast continues to follow the trend of the bulk of the guidance
and takes Joaquin toward the U.S east coast. The NHC track is
similar to the previous advisory and is once again east of the
multi-model consensus.  The NOAA G-IV aircraft has recently
completed its synoptic surveillance flight, and data collected
during this mission should be assimilated into the 0000 UTC models,
hopefully reducing the spread of the track guidance.

The upper-level wind pattern over the hurricane is forecast by the
global models to become even more conducive during the next couple
of days.  This favors additional intensification, with the only
possible limiting factors being upwelling of cool SSTs beneath the
slow-moving hurricane and eyewall cycles which could cause some
fluctuations in intensity.  By 72 hours, increasing southwesterly
shear, dry air intrusion, and lower SSTs are expected to cause
gradual weakening.  The updated NHC intensity forecast has been
significantly increased from the previous advisory primarily due to
the higher initial intensity. The official forecast is between the
lower statistical guidance and the higher HWRF during the first
36-48 hours, and is near the SHIPS/LGEM guidance after that time.


KEY MESSAGES:

1.  Preparations to protect life and property within the warning
areas in the Central Bahamas should be completed now.

2.  Confidence in the details of the forecast after 72 hours remains
low, since we have one normally excellent model that keeps Joaquin
far away from the United States east coast.   The range of possible
outcomes is still large, and includes the possibility of a major
hurricane landfall in the Carolinas.

3.  Every effort is being made to provide the forecast models with
as much data as possible.  The NOAA G-IV jet has begun a series of
missions in the storm environment, and the National Weather Service
has begun launching extra balloon soundings.

4.  Because landfall, if it occurs, is still more than three days
away, it's too early to talk about specific wind, rain, or surge
impacts from Joaquin in the United States.  Regardless of Joaquin's
track, strong onshore winds will create minor to moderate coastal
flooding along the coasts of the mid-Atlantic and northeastern
states through the weekend.

5.  A hurricane watch for a portion of the U.S. coast could be
required as early as Thursday evening.

6. Many portions of the eastern U.S. are currently experiencing
heavy rains and gusty winds associated with a frontal system. These
heavy rains are likely to continue for the next few days, even if
the center of Joaquin stays offshore.  The resulting inland flood
potential could complicate preparations for Joaquin should it head
toward the coast, and even more substantial inland flooding is
possible if Joaquin later passes near or over these same areas.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 23.8N  73.1W  100 KT 115 MPH
12H  01/1200Z 23.5N  73.8W  110 KT 125 MPH
24H  02/0000Z 23.6N  74.5W  120 KT 140 MPH
36H  02/1200Z 24.7N  74.8W  120 KT 140 MPH
48H  03/0000Z 26.6N  74.7W  110 KT 125 MPH
72H  04/0000Z 31.6N  74.7W   95 KT 110 MPH
96H  05/0000Z 36.2N  75.6W   85 KT 100 MPH
120H  06/0000Z 38.5N  76.5W   55 KT  65 MPH

$$
Forecaster Brown

實測進行中 最大風力約100節

blackcat

krichard2011

之前都沒在關注一進來看了一下不得了
結構相當漂亮 連風眼都快要開啦
大西洋似乎已經好一段時間沒這種貨色了
NHC 已經提升至 110 KT 上看120KT
部分模式系集甚至上看五級颶風...


INIT  01/1500Z 23.0N  73.9W  110 KT 125 MPH
12H  02/0000Z 22.9N  74.2W  115 KT 130 MPH
24H  02/1200Z 23.7N  74.6W  120 KT 140 MPH
36H  03/0000Z 25.2N  74.4W  120 KT 140 MPH
48H  03/1200Z 27.5N  73.7W  110 KT 125 MPH
72H  04/1200Z 32.0N  73.0W   95 KT 110 MPH
96H  05/1200Z 36.0N  73.5W   75 KT  85 MPH
120H  06/1200Z 40.0N  72.5W   55 KT  65 MPH