霧峰追風者

  二級颶風  
編號：19 L
名稱：Sally

  基本資料  
擾動編號日期：2020 年 09 月 11 日 13 時
命名日期　　：2020 年 09 月 13 日 02 時
撤編日期　　：2020 年 09 月 18 日 15 時
登陸地點　　：美國-阿拉巴馬州

  巔峰時期資料  
近中心最強風速 ：90  kt( Cat.2 )
海平面最低氣壓 ：965 百帕
  擾動編號資料  
96L.INVEST.15kts-1008mb-27N-85W

2. Another trough of low pressure is located over the north-central
Gulf of Mexico.  Although the associated shower and thunderstorm
activity has diminished since earlier today, some slow development
of this system is possible while it moves westward and then
southwestward over the northern and western Gulf of Mexico
through early next week.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...20 percent.

以上資料來自：NHC、颱風論壇整理製作

老農民版夜神月

NHC將96L重新定位至美國東南方近海，因此應該是1.

1. A large area of disorganized showers and thunderstorms extending
from near the Central and Northwest Bahamas eastward over the
western Atlantic for a few hundred miles is associated with a
surface trough of low pressure.  This system is forecast to
move westward, crossing the Bahamas and Florida on Friday and moving
into the eastern Gulf of Mexico over the weekend.  Upper-level
winds are expected to become conducive for development, and a
tropical depression could form while this system moves slowly
west-northwestward over the eastern Gulf of Mexico early next week.
Regardless of development, this system is expected to produce
locally heavy rainfall over portions of South Florida and the Keys
during the next couple of days.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...medium...50 percent.

老農民版夜神月

NHC展望提升至High,70%

1. Shower and thunderstorm activity located over the northwestern and
central Bahamas and the adjacent waters continues to shows signs of
organization.  In addition, surface observations indicate that
pressures have fallen over the area since yesterday and, along with
wind and satellite data, suggest that a broad area of low pressure
could be forming between the northwestern Bahamas and South Florida.
This system is forecast to move westward at about 10 mph, and it
could become a tropical depression while it is near South Florida
tonight.  But if not, the disturbance is expected to become a
tropical depression while it moves slowly west-northwestward over
the northeastern Gulf of Mexico this weekend and early next week.  
Regardless of development, this system is expected to produce
locally heavy rainfall over portions of the Bahamas, South Florida,
and the Florida Keys during the next couple of days, and interests
there, as well as along the northern and eastern Gulf coast, should
monitor its progress.
* Formation chance through 48 hours...high...70 percent.
* Formation chance through 5 days...high...80 percent.

老農民版夜神月

FWC-N發布TCFA

WTNT21 KNGU 111800
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/1.FORMATION OF A SIGNIFICANT
TROPICAL CYCLONE IS POSSIBLE WITHIN
100 NM EITHER SIDE OF A LINE FROM 25.0N 78.1W TO 26.7N 83.5W
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 25 KNOTS. METSAT
IMAGERY AT 111600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 25.0N 78.0W. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 08
KNOTS.
2.REMARKS: A LARGE AREA OF SHOWERS AND THUNDERSTORMS
ASSOCIATED WITH A DEVELOPING BROAD AREA OF LOW
PRESSURE NEAR ANDROS ISLAND, BAHAMAS CONTIUES TO BECOME BETTER
ORGANIZED. SURFACE OBSERVATIONS IN THE NORTHWESTERN AND CENTRAL
BAHAMAS INDICATE THAT PRESSURES HAVE FALLEN 4 MB DURING THE PAST
24 HOURS. IF THESE DEVELOPMENTAL TRENDS CONTINUE A TROPICAL
DEPRESSION COULD FORM JUST PRIOR TO REACHING THE SOUTH FLORIDA
COAST LATE TONIGHT OR WHILE IT MOVES GENERALLY WEST-NORTHWESTWARD
AND ENTERS THE EASTERN GULF OF MEXICO ON SATURDAY.
3.THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
121800Z.//
BT
#0001
NNNN

周子堯@FB

升格19L，首報上望60kts，或將進入墨西哥灣，再發展

148
WTNT44 KNHC 112059
TCDAT4

Tropical Depression Nineteen Discussion Number   1
NWS National Hurricane Center Miami FL       AL192020
500 PM EDT Fri Sep 11 2020

GOES-16 1-minute satellite data show that the system near the
Bahamas that we have been monitoring for the past couple of days
has quickly organized into a tropical depression.  Very deep
convection has formed near the center, and the 1-min data now shows
enough north and northwest flow to indicate that a well-defined
center is present.  The initial wind speed is 30 kt in agreement
with recent ship data.  

It is uncertain whether the large burst of convection over the
center will continue and cause the depression to become a tropical
storm before reaching Florida.  However, since it is only a 5 kt
increase from the current intensity, it is possible that tropical
storm conditions could still occur along the southeast Florida coast
late tonight, and a tropical storm watch has been issued.  
Otherwise, after the system reaches the eastern Gulf of Mexico,
steady intensification is expected through the weekend due to
expected light wind shear and very warm water. Some increase in
shear could occur over the northern Gulf of Mexico but that is
uncertain at this time.  The first forecast will stay conservative
and only show a peak intensity of 60 kt in 3 to 4 days, but do not
be surprised if that is revised upward on later forecasts once
other models better initialize the depression.

An uncertain estimate of the initial motion is 285/7. Strong
ridging over the southeastern United States is expected to steer the
cyclone to the west-northwest then northwest as a mid-latitude
trough erodes the western side of the ridge over the weekend.  The
forecast gets tricky after that because the bulk of the guidance
suggests the trough isn't deep enough to recurve the system, and
instead it gets left behind, moving slowly westward early next week
due to weak ridging over the southern Plains.  The NHC forecast is
near the corrected-consensus guidance.  The uncertainty in the
track forecast is much larger than normal after 48 hours, as small
changes in the forecast steering flow could result in this system
moving over the northern Gulf Coast faster and to the northeast of
what is shown here. As a result, the risk of seeing direct impacts
from this system extends well outside the cone of uncertainty, even
more so than usual in this case.

KEY MESSAGES:

1. Heavy rainfall is expected to produce isolated flash flooding
over portions of central and southern Florida and prolong existing
minor river flooding in the Tampa Bay area.

2. Tropical storm conditions are possible tonight along the
southeast Florida coast where a Tropical Storm Watch is in effect.  

3. The system is forecast to strengthen to near hurricane intensity
by early next week as it moves across the northeastern Gulf of
Mexico. Dangerous impacts from storm surge, wind, and heavy rainfall
will be possible along the Gulf Coast from the Florida Panhandle to
southeastern Louisiana this weekend and early next week. Residents
in these areas should monitor the progress of this system and
updates to the forecast, as Storm Surge, Tropical Storm or Hurricane
watches could be issued later tonight and Saturday.

FORECAST POSITIONS AND MAX WINDS

INIT  11/2100Z 25.4N  79.0W   30 KT  35 MPH
12H  12/0600Z 25.7N  80.1W   30 KT  35 MPH
24H  12/1800Z 26.2N  81.9W   30 KT  35 MPH
36H  13/0600Z 27.3N  83.8W   35 KT  40 MPH
48H  13/1800Z 28.4N  85.2W   45 KT  50 MPH
60H  14/0600Z 29.1N  86.3W   55 KT  65 MPH
72H  14/1800Z 29.5N  87.4W   60 KT  70 MPH
96H  15/1800Z 30.0N  89.0W   60 KT  70 MPH
120H  16/1800Z 31.0N  91.0W   25 KT  30 MPH...INLAND

$$
Forecaster Blake

老農民版夜神月

NHC18Z升格TS,命名Sally

428
WTNT84 KNHC 121803
TCVAT4

SALLY WATCH/WARNING INTERMEDIATE ADVISORY NUMBER 4A
NWS NATIONAL HURRICANE CENTER MIAMI FL     AL192020
203 PM EDT SAT SEP 12 2020

.TROPICAL STORM SALLY

CAUTION...THIS PRODUCT ONLY APPROXIMATELY CONVEYS THE EXTENT OF
TROPICAL CYCLONE WIND AND SURGE WATCHES AND WARNINGS. PLEASE SEE
THE LATEST PUBLIC ADVISORY FROM THE NATIONAL HURRICANE CENTER FOR
THE PRECISE LATERAL EXTENT OF WIND WATCHES AND WARNINGS ALONG THE
COAST...AS WELL AS THE APPROXIMATE LATERAL EXTENT OF SURGE WATCHES
AND WARNINGS. THE PRECISE EXTENT OF SURGE WATCHES AND WARNINGS
CAN BE FOUND IN THE NWS NATIONAL DIGITAL FORECAST DATABASE HAZARD
GRIDS.

FLZ108-112-114-115-130215-
/O.CON.KNHC.TR.A.1019.000000T0000Z-000000T0000Z/
203 PM EDT SAT SEP 12 2020 /103 PM CDT SAT SEP 12 2020/

$$

ATTN...WFO...TAE...

老農民版夜神月

於墨西哥灣中發展超乎預期,15Z強度已達80KT,觸陸前上望90節

ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM

Hurricane Sally Special Discussion Number  13
NWS National Hurricane Center Miami FL       AL192020
1130 AM CDT Mon Sep 14 2020

A NOAA Hurricane Hunter aircraft investigating Sally recently
measured peak flight-level winds of 88 kt at 700 mb and SFMR winds
of 78 kt north of the center, and an Air Force reconnaissance
aircraft just measured 79 kt flight-level winds at 700 mb.  These
data indicate that Sally has rapidly strengthened into a hurricane
with an intensity of around 80 kt. In addition, data from the KEVX
WSR-88D show an eye forming at around 16,000 ft altitude. This
special advisory has been issued to increase the initial and
forecast intensity. Additional adjustments to the intensity forecast
could be required this afternoon.  Only a slight adjustment was made
to the 12-h track forecast position based on the more northward and
eastward initial position.

KEY MESSAGES:

1. It is too early to determine where Sally's center will move
onshore given the uncertainty in the timing and location of Sally's
northward turn near the central Gulf Coast.  Users should not focus
on the details of the official forecast track, since NHC's average
forecast error at 48 hours is around 80 miles, and dangerous storm
surge, rainfall, and wind hazards will extend well away from the
center.

2. An extremely dangerous and life-threatening storm surge is
expected for areas outside the southeastern Louisiana Hurricane and
Storm Damage Risk Reduction System from Port Fourchon, Louisiana, to
the Alabama/Florida border, where a Storm Surge Warning is in
effect. Residents in these areas should follow any advice given by
local officials.

3. Hurricane conditions are expected tonight within the Hurricane
Warning area in southeastern Louisiana and are expected by late
Tuesday within the Hurricane Warning area along the Mississippi and
Alabama coastline. Tropical storm conditions are likely to begin
later today and this evening in these areas and preparations
should be rushed to completion.

4. Life-threatening flash flooding is likely, as well as widespread
minor to isolated major flooding, on area rivers along and just
inland of the Central Gulf Coast. Significant flash and urban
flooding, as well as widespread minor to moderate river flooding is
likely across Mississippi and Alabama through the middle of the
week.  Flooding impacts are expected to spread farther across the
Southeast through the week. Sally could continue to produce flash
flooding across the Florida peninsula and prolong existing minor
river flooding across west-central Florida through today.


FORECAST POSITIONS AND MAX WINDS

INIT  14/1630Z 28.7N  87.0W   80 KT  90 MPH
12H  15/0000Z 28.8N  87.8W   85 KT 100 MPH
24H  15/1200Z 29.2N  88.8W   90 KT 105 MPH
36H  16/0000Z 29.8N  89.1W   90 KT 105 MPH
48H  16/1200Z 30.8N  88.7W   65 KT  75 MPH...INLAND
60H  17/0000Z 31.8N  87.7W   30 KT  35 MPH...INLAND
72H  17/1200Z 32.6N  86.5W   25 KT  30 MPH...INLAND
96H  18/1200Z 33.1N  84.0W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  19/1200Z...DISSIPATED

$$
Forecaster Brown

NNNN

老農民版夜神月

相較昨晚略微減弱,Sally現位於美國南方海域,NHC認為將維持現在的強度登陸

FORECAST POSITIONS AND MAX WINDS

INIT  15/1500Z 29.1N  88.2W   75 KT  85 MPH
12H  16/0000Z 29.6N  88.2W   75 KT  85 MPH
24H  16/1200Z 30.2N  88.1W   70 KT  80 MPH
36H  17/0000Z 31.0N  87.6W   55 KT  65 MPH...INLAND
48H  17/1200Z 31.9N  86.6W   35 KT  40 MPH...INLAND
60H  18/0000Z 32.6N  85.2W   25 KT  30 MPH...INLAND
72H  18/1200Z 33.0N  83.6W   20 KT  25 MPH...POST-TROP/REMNT LOW
96H  19/1200Z...DISSIPATED