Major Hurricane Florence/Hurricane Warnings Hoisted SC/NC

Tropical Weather Discussions and Analysis
unome
Posts: 3059
Joined: Fri Feb 12, 2010 6:11 pm

https://www.nhc.noaa.gov/#Florence
https://www.nhc.noaa.gov/refresh/graphi ... k#contents

11:00 PM AST Sun Sep 9
Location: 24.6°N 57.7°W
Moving: W at 7 mph
Min pressure: 974 mb
Max sustained: 90 mph

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663 
WTNT41 KNHC 100248
TCDAT1

Hurricane Florence Discussion Number  43
NWS National Hurricane Center Miami FL       AL062018
1100 PM AST Sun Sep 09 2018

Florence's satellite appearance has continued to improve quite
markedly since the previous advisory. An eye was evident in GOES-16
high-resolution infrared imagery and other channels between
2300-0000 UTC, but it became cloud covered immediately thereafter
due to a strong burst of deep convection in the southern and eastern
eyewall where cloud tops colder than -80C and an abundance of
lightning activity was observed. Since that time, the CDO has
expanded and become more circular, outflow has increased and become
more symmetrical, and an eye has begun to re-appear. The initial
intensity has been increased to 80 kt for this advisory based on a
subjective Dvorak intensity estimate of T4.5/77 kt from SAB and NHC
objective intensity estimates ranging from 77 kt to 87 kt.

The initial motion estimate is 280/06 kt. Once again, there is no
significant change to the previous forecast track or synoptic
reasoning. The models appear to be getting better dialed in on both
the location and strength of the developing blocking ridge in the
vicinity of Bermuda during the next 4 days as the mid-latitude flow
amplifies across the CONUS and the northwestern Atlantic. In fact,
the global models are now in very good agreement on forecasting
Florence's upper-level mass outflow being deposited to the north and
east of the hurricane, which will act to further strengthen the
blocking ridge and help to drive the hurricane northwestward toward
the southeastern U.S. coastal region. The new NHC model guidance is
even more tightly packed about the previous forecast track, with
less than a 90 n mi cross-track spread at 72 h and less than 120 n
mi spread at 96 h, just prior to expected landfall. Therefore, the
new official advisory track is essentially just an update and
extension of the previous forecast, and lies between the nearly
juxtaposed HCCA and FSSE corrected consensus track models.

Now that Florence has developed an inner-core ring of deep
convection, which has insulated the eye from intrusions of dry air,
rapid intensification appears likely to begin soon and continue for
the next 36 hours or so due to the expected very low vertical wind
shear conditions, dual outflow jet pattern that will be developing,
and very warm SSTs of 29-29.5 deg C beneath the hurricane. The most
favorable combination of the aforementioned factors will occur in
about 48 h, and that's when Florence is likely to achieve its
maximum intensity.  After 72 hours, the wind shear is expected to
increase to around 10-15 kt from the south or southwest, and the
dual outflow pattern is forecast to change to only a single poleward
outflow pattern. This slight degradation in the upper-level
environment, along with slightly cooler SSTs, is expected to result
in a gradual weakening of the powerful cyclone. However, Florence is
still forecast to be near category-4 strength when the dangerous
hurricane makes landfall. The official intensity forecast is an
average of the intensity forecast from the corrected consensus
models HCCA and FSSE, with the latter explicitly forecasting a peak
intensity of 134 kt in 72 hours. It is also worth noting that the
model guidance is also significantly increasing the size of
Florence's wind field over the next few days, and the official
forecast reflects this trend.

The NOAA G-IV jet will conduct another synoptic surveillance
mission early Monday morning in support of the 1200 UTC model
cycle, and these flights will continue through Tuesday. In addition,
upper-air stations across portions of the central and eastern U.S.
are conducting special 0600 UTC and 1800 UTC radiosonde launches to
collect extra data for the numerical models. Hopefully these data
will help improve the track and intensity forecasts.

Key Messages:

1. There is an increasing risk of two life-threatening impacts from
Florence: storm surge at the coast and freshwater flooding from a
prolonged heavy rainfall event inland. While it is too soon to
determine the exact timing, location, and magnitude of these
impacts, interests at the coast and inland from South Carolina into
the mid-Atlantic region should closely monitor the progress of
Florence, ensure they have their hurricane plan in place, and follow
any advice given by local officials.

2. Large swells affecting Bermuda and portions of the U.S. East
Coast will continue this week.  These swells will result in
life-threatening surf and rip currents.


FORECAST POSITIONS AND MAX WINDS

INIT  10/0300Z 24.6N  57.7W   80 KT  90 MPH
 12H  10/1200Z 24.9N  59.1W   90 KT 105 MPH
 24H  11/0000Z 25.6N  61.5W  105 KT 120 MPH
 36H  11/1200Z 26.5N  64.4W  120 KT 140 MPH
 48H  12/0000Z 27.8N  67.6W  130 KT 150 MPH
 72H  13/0000Z 31.2N  73.6W  130 KT 150 MPH
 96H  14/0000Z 34.0N  77.5W  120 KT 140 MPH
120H  15/0000Z 35.2N  79.0W   55 KT  65 MPH...INLAND

$$
Forecaster Stewart

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296 
FONT11 KNHC 100248
PWSAT1

HURRICANE FLORENCE WIND SPEED PROBABILITIES NUMBER  43              
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062018               
0300 UTC MON SEP 10 2018                                            

AT 0300Z THE CENTER OF HURRICANE FLORENCE WAS LOCATED NEAR LATITUDE 
24.6 NORTH...LONGITUDE 57.7 WEST WITH MAXIMUM SUSTAINED WINDS NEAR  
80 KTS...90 MPH...150 KM/H.                                         

Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH)                  
   ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME      
   EASTERN  DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME      
   CENTRAL  DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME      

WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS                 

CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST     
   ...34 KT (39 MPH... 63 KM/H)...                                  
   ...50 KT (58 MPH... 93 KM/H)...                                  
   ...64 KT (74 MPH...119 KM/H)...                                  
FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS               

PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE               
    OP  IS THE PROBABILITY OF THE EVENT BEGINNING DURING            
        AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY)               
   (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN           
        00Z MON AND THE FORECAST HOUR (CUMULATIVE PROBABILITY)      

PROBABILITIES ARE GIVEN IN PERCENT                                  
X INDICATES PROBABILITIES LESS THAN 1 PERCENT                       
PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN
THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT.             
PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY              
64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT.                 


  - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - -   

               FROM    FROM    FROM    FROM    FROM    FROM    FROM 
  TIME       00Z MON 12Z MON 00Z TUE 12Z TUE 00Z WED 00Z THU 00Z FRI
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             12Z MON 00Z TUE 12Z TUE 00Z WED 00Z THU 00Z FRI 00Z SAT

FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   

ISLIP NY       34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

NYC JFK AIRPRT 34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

NYC CNTRL PARK 34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

NEWARK NJ      34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

TRENTON NJ     34  X   X( X)   X( X)   X( X)   X( X)   2( 2)   5( 7)

NWS EARLE NJ   34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   4( 5)

ALLENTOWN PA   34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   5( 6)

PHILADELPHIA   34  X   X( X)   X( X)   X( X)   X( X)   3( 3)   7(10)

ATLANTIC CITY  34  X   X( X)   X( X)   X( X)   X( X)   5( 5)   6(11)

BALTIMORE MD   34  X   X( X)   X( X)   X( X)   X( X)   8( 8)  12(20)
BALTIMORE MD   50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

DOVER DE       34  X   X( X)   X( X)   X( X)   X( X)   8( 8)  10(18)
DOVER DE       50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

ANNAPOLIS MD   34  X   X( X)   X( X)   X( X)   X( X)  10(10)  13(23)
ANNAPOLIS MD   50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   3( 4)
ANNAPOLIS MD   64  X   X( X)   X( X)   X( X)   X( X)   X( X)   1( 1)

WASHINGTON DC  34  X   X( X)   X( X)   X( X)   X( X)  11(11)  15(26)
WASHINGTON DC  50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   3( 4)
WASHINGTON DC  64  X   X( X)   X( X)   X( X)   X( X)   X( X)   1( 1)

CAPE HENLOPEN  34  X   X( X)   X( X)   X( X)   X( X)  12(12)   8(20)
CAPE HENLOPEN  50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)
CAPE HENLOPEN  64  X   X( X)   X( X)   X( X)   X( X)   X( X)   1( 1)

OCEAN CITY MD  34  X   X( X)   X( X)   X( X)   X( X)  16(16)  11(27)
OCEAN CITY MD  50  X   X( X)   X( X)   X( X)   X( X)   2( 2)   3( 5)
OCEAN CITY MD  64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   1( 2)

PAX RIVER NAS  34  X   X( X)   X( X)   X( X)   X( X)  18(18)  16(34)
PAX RIVER NAS  50  X   X( X)   X( X)   X( X)   X( X)   2( 2)   4( 6)
PAX RIVER NAS  64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   1( 2)

WALLOPS CDA    34  X   X( X)   X( X)   X( X)   X( X)  19(19)  13(32)
WALLOPS CDA    50  X   X( X)   X( X)   X( X)   X( X)   3( 3)   3( 6)
WALLOPS CDA    64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

CHARLOTTESVIL  34  X   X( X)   X( X)   X( X)   X( X)  20(20)  25(45)
CHARLOTTESVIL  50  X   X( X)   X( X)   X( X)   X( X)   1( 1)   9(10)
CHARLOTTESVIL  64  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)

RICHMOND VA    34  X   X( X)   X( X)   X( X)   X( X)  28(28)  24(52)
RICHMOND VA    50  X   X( X)   X( X)   X( X)   X( X)   6( 6)  11(17)
RICHMOND VA    64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   6( 7)

DANVILLE VA    34  X   X( X)   X( X)   X( X)   X( X)  34(34)  36(70)
DANVILLE VA    50  X   X( X)   X( X)   X( X)   X( X)   8( 8)  22(30)
DANVILLE VA    64  X   X( X)   X( X)   X( X)   X( X)   2( 2)   7( 9)

NORFOLK NAS    34  X   X( X)   X( X)   X( X)   X( X)  35(35)  19(54)
NORFOLK NAS    50  X   X( X)   X( X)   X( X)   X( X)  10(10)   9(19)
NORFOLK NAS    64  X   X( X)   X( X)   X( X)   X( X)   3( 3)   6( 9)

NORFOLK VA     34  X   X( X)   X( X)   X( X)   X( X)  36(36)  19(55)
NORFOLK VA     50  X   X( X)   X( X)   X( X)   X( X)  11(11)   8(19)
NORFOLK VA     64  X   X( X)   X( X)   X( X)   X( X)   4( 4)   5( 9)

OCEANA NAS VA  34  X   X( X)   X( X)   X( X)   1( 1)  36(37)  19(56)
OCEANA NAS VA  50  X   X( X)   X( X)   X( X)   X( X)  11(11)   8(19)
OCEANA NAS VA  64  X   X( X)   X( X)   X( X)   X( X)   4( 4)   5( 9)

ELIZABETH CTY  34  X   X( X)   X( X)   X( X)   1( 1)  47(48)  19(67)
ELIZABETH CTY  50  X   X( X)   X( X)   X( X)   X( X)  19(19)  10(29)
ELIZABETH CTY  64  X   X( X)   X( X)   X( X)   X( X)   8( 8)   6(14)

GREENSBORO NC  34  X   X( X)   X( X)   X( X)   X( X)  34(34)  36(70)
GREENSBORO NC  50  X   X( X)   X( X)   X( X)   X( X)   8( 8)  22(30)
GREENSBORO NC  64  X   X( X)   X( X)   X( X)   X( X)   2( 2)   8(10)

RALEIGH NC     34  X   X( X)   X( X)   X( X)   X( X)  48(48)  33(81)
RALEIGH NC     50  X   X( X)   X( X)   X( X)   X( X)  20(20)  28(48)
RALEIGH NC     64  X   X( X)   X( X)   X( X)   X( X)   7( 7)  18(25)

ROCKY MT NC    34  X   X( X)   X( X)   X( X)   X( X)  54(54)  28(82)
ROCKY MT NC    50  X   X( X)   X( X)   X( X)   X( X)  27(27)  23(50)
ROCKY MT NC    64  X   X( X)   X( X)   X( X)   X( X)  12(12)  15(27)

CAPE HATTERAS  34  X   X( X)   X( X)   X( X)  12(12)  63(75)   7(82)
CAPE HATTERAS  50  X   X( X)   X( X)   X( X)   1( 1)  37(38)   6(44)
CAPE HATTERAS  64  X   X( X)   X( X)   X( X)   X( X)  19(19)   4(23)

FAYETTEVILLE   34  X   X( X)   X( X)   X( X)   1( 1)  59(60)  25(85)
FAYETTEVILLE   50  X   X( X)   X( X)   X( X)   X( X)  32(32)  27(59)
FAYETTEVILLE   64  X   X( X)   X( X)   X( X)   X( X)  16(16)  19(35)

CHARLOTTE NC   34  X   X( X)   X( X)   X( X)   X( X)  28(28)  29(57)
CHARLOTTE NC   50  X   X( X)   X( X)   X( X)   X( X)   4( 4)  18(22)
CHARLOTTE NC   64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   6( 7)

CHERRY PT NC   34  X   X( X)   X( X)   X( X)   3( 3)  70(73)  15(88)
CHERRY PT NC   50  X   X( X)   X( X)   X( X)   X( X)  47(47)  16(63)
CHERRY PT NC   64  X   X( X)   X( X)   X( X)   X( X)  26(26)  13(39)

NEW RIVER NC   34  X   X( X)   X( X)   X( X)  13(13)  74(87)   6(93)
NEW RIVER NC   50  X   X( X)   X( X)   X( X)   1( 1)  56(57)   9(66)
NEW RIVER NC   64  X   X( X)   X( X)   X( X)   X( X)  34(34)   9(43)

MOREHEAD CITY  34  X   X( X)   X( X)   X( X)  11(11)  76(87)   6(93)
MOREHEAD CITY  50  X   X( X)   X( X)   X( X)   1( 1)  57(58)  10(68)
MOREHEAD CITY  64  X   X( X)   X( X)   X( X)   X( X)  36(36)  10(46)

SURF CITY NC   34  X   X( X)   X( X)   X( X)   3( 3)  74(77)  13(90)
SURF CITY NC   50  X   X( X)   X( X)   X( X)   X( X)  51(51)  17(68)
SURF CITY NC   64  X   X( X)   X( X)   X( X)   X( X)  33(33)  15(48)

WILMINGTON NC  34  X   X( X)   X( X)   X( X)   2( 2)  72(74)  15(89)
WILMINGTON NC  50  X   X( X)   X( X)   X( X)   X( X)  49(49)  19(68)
WILMINGTON NC  64  X   X( X)   X( X)   X( X)   X( X)  29(29)  16(45)

BALD HEAD ISL  34  X   X( X)   X( X)   X( X)   7( 7)  76(83)   7(90)
BALD HEAD ISL  50  X   X( X)   X( X)   X( X)   1( 1)  55(56)  13(69)
BALD HEAD ISL  64  X   X( X)   X( X)   X( X)   X( X)  36(36)  12(48)

FLORENCE SC    34  X   X( X)   X( X)   X( X)   X( X)  47(47)  25(72)
FLORENCE SC    50  X   X( X)   X( X)   X( X)   X( X)  20(20)  19(39)
FLORENCE SC    64  X   X( X)   X( X)   X( X)   X( X)  10(10)  13(23)

COLUMBIA SC    34  X   X( X)   X( X)   X( X)   X( X)  27(27)  23(50)
COLUMBIA SC    50  X   X( X)   X( X)   X( X)   X( X)   7( 7)  12(19)
COLUMBIA SC    64  X   X( X)   X( X)   X( X)   X( X)   2( 2)   6( 8)

LITTLE RIVER   34  X   X( X)   X( X)   X( X)   2( 2)  64(66)  17(83)
LITTLE RIVER   50  X   X( X)   X( X)   X( X)   X( X)  38(38)  19(57)
LITTLE RIVER   64  X   X( X)   X( X)   X( X)   X( X)  22(22)  13(35)

MYRTLE BEACH   34  X   X( X)   X( X)   X( X)   3( 3)  68(71)  10(81)
MYRTLE BEACH   50  X   X( X)   X( X)   X( X)   X( X)  38(38)  13(51)
MYRTLE BEACH   64  X   X( X)   X( X)   X( X)   X( X)  21(21)  11(32)

GEORGETOWN SC  34  X   X( X)   X( X)   X( X)   1( 1)  49(50)  18(68)
GEORGETOWN SC  50  X   X( X)   X( X)   X( X)   X( X)  24(24)  14(38)
GEORGETOWN SC  64  X   X( X)   X( X)   X( X)   X( X)  12(12)  10(22)

CHARLESTON SC  34  X   X( X)   X( X)   X( X)   1( 1)  33(34)  16(50)
CHARLESTON SC  50  X   X( X)   X( X)   X( X)   X( X)  12(12)  10(22)
CHARLESTON SC  64  X   X( X)   X( X)   X( X)   X( X)   6( 6)   5(11)

BEAUFORT MCAS  34  X   X( X)   X( X)   X( X)   X( X)  22(22)  14(36)
BEAUFORT MCAS  50  X   X( X)   X( X)   X( X)   X( X)   6( 6)   7(13)
BEAUFORT MCAS  64  X   X( X)   X( X)   X( X)   X( X)   2( 2)   4( 6)

ATLANTA GA     34  X   X( X)   X( X)   X( X)   X( X)   3( 3)   7(10)

AUGUSTA GA     34  X   X( X)   X( X)   X( X)   X( X)  15(15)  16(31)
AUGUSTA GA     50  X   X( X)   X( X)   X( X)   X( X)   2( 2)   5( 7)
AUGUSTA GA     64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

SAVANNAH GA    34  X   X( X)   X( X)   X( X)   X( X)  14(14)  13(27)
SAVANNAH GA    50  X   X( X)   X( X)   X( X)   X( X)   3( 3)   4( 7)
SAVANNAH GA    64  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

KINGS BAY GA   34  X   X( X)   X( X)   X( X)   X( X)   6( 6)   6(12)

WAYCROSS GA    34  X   X( X)   X( X)   X( X)   X( X)   5( 5)   6(11)

MAYPORT NS FL  34  X   X( X)   X( X)   X( X)   X( X)   7( 7)   5(12)

JACKSONVILLE   34  X   X( X)   X( X)   X( X)   X( X)   4( 4)   5( 9)

GAINESVILLE FL 34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)

DAYTONA BEACH  34  X   X( X)   X( X)   X( X)   X( X)   2( 2)   1( 3)

COLUMBUS GA    34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   4( 5)

BERMUDA        34  X   X( X)   X( X)   2( 2)   2( 4)   X( 4)   X( 4)

$$                                                                  
FORECASTER STEWART                                                  
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Rip76
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Wow...

down to 945
130kt FL in NE eyewall
unome
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Rip76 wrote:Wow...

down to 945
130kt FL in NE eyewall
yup, a cat 4 now - should take out the "Possible" in thread title
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srainhoutx
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unome wrote:
Rip76 wrote:Wow...

down to 945
130kt FL in NE eyewall
yup, a cat 4 now - should take out the "Possible" in thread title
Updated Topic to include Major Hurricane and change to Likely. It's a typical busy Monday work wise for me... ;)
Carla/Alicia/Jerry(In The Eye)/Michelle/Charley/Ivan/Dennis/Katrina/Rita/Wilma/Humberto/Ike/Harvey

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unome
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Joined: Fri Feb 12, 2010 6:11 pm

srainhoutx wrote:Updated Topic to include Major Hurricane and change to Likely. It's a typical busy Monday work wise for me... ;)
thank you, as always :)
unome
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Joined: Fri Feb 12, 2010 6:11 pm

a post from Chris Hollis of Tropical Atlantic.com , images of recon with IR satellite, stunning

https://canetalk.com/2018/09/1536605407 ... 6109.shtml

more recon options: http://hurricanecity.com/recon/ (they mirror Tropical Atlantic.com to reduce strain on their server)
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srainhoutx
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Florence has completed an Eye Wall Replacement Cycle with a much larger eye of about 50 miles wide. This should lead to a much larger storm and allow for re intensification throughout the day.

Image
Carla/Alicia/Jerry(In The Eye)/Michelle/Charley/Ivan/Dennis/Katrina/Rita/Wilma/Humberto/Ike/Harvey

Member: National Weather Association
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unome
Posts: 3059
Joined: Fri Feb 12, 2010 6:11 pm

https://www.nhc.noaa.gov/#Florence
https://www.nhc.noaa.gov/refresh/graphi ... e#contents

Code: Select all

WTNT31 KNHC 112040
TCPAT1

BULLETIN
Hurricane Florence Advisory Number  50
NWS National Hurricane Center Miami FL       AL062018
500 PM AST Tue Sep 11 2018

...DANGEROUS FLORENCE EXPECTED TO BRING LIFE-THREATENING STORM
SURGE AND RAINFALL TO PORTIONS OF THE CAROLINAS AND MID-ATLANTIC...


SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...27.5N 67.1W
ABOUT 360 MI...580 KM SSW OF BERMUDA
ABOUT 785 MI...1260 KM ESE OF CAPE FEAR NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...140 MPH...220 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...945 MB...27.91 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

A Storm Surge Warning has been issued from South Santee
River, South Carolina, to Duck, North Carolina, and the Albemarle
and Pamlico Sounds, including the Neuse and Pamlico Rivers.

A Hurricane Warning has been issued from South Santee
River, South Carolina, to Duck, North Carolina, and the Albemarle
and Pamlico Sounds.

A Tropical Storm Watch has been issued from north of the North
Carolina/Virginia border to Cape Charles Light, Virginia, and for
the Chesapeake Bay south of New Point Comfort.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds, including the Neuse and Pamlico
Rivers

A Storm Surge Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Hurricane Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds

A Hurricane Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Tropical Storm Watch is in effect for...
* North of the North Carolina/Virginia border to Cape Charles Light
Virginia
* Chesapeake Bay south of New Point Comfort

Interests elsewhere in the southeastern and mid-Atlantic states
should monitor the progress of Florence.  Additional watches and
warnings may be required tonight or Wednesday.

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.  This is a life-threatening situation.  Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions.  Promptly follow evacuation and other
instructions from local officials.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.  A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous.  Preparations to protect life and property should be
rushed to completion.

A Hurricane Watch means that hurricane conditions are possible
within the watch area.  A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of the eye of Hurricane
Florence was located by satellite near latitude 27.5 North,
longitude 67.1 West. Florence is moving toward the west-northwest
near 17 mph (28 km/h). A motion toward the west-northwest and
northwest is expected through early Thursday. Florence is expected
to slow down considerably by late Thursday into Friday. On the
forecast track, the center of Florence will move over the
southwestern Atlantic Ocean between Bermuda and the Bahamas through
Wednesday, and approach the coast of North Carolina or South
Carolina in the hurricane warning area on Thursday and Friday.

Maximum sustained winds have increased to near 140 mph (220 km/h)
with higher gusts.  Florence is a category 4 hurricane on the
Saffir-Simpson Hurricane Wind Scale.  Further strengthening is
forecast tonight and Wednesday.  While some weakening is expected on
Thursday, Florence is forecast to be an extremely dangerous major
hurricane through landfall.

Hurricane-force winds extend outward up to 60 miles (95 km) from the
center and tropical-storm-force winds extend outward up to 175 miles
(280 km).

The estimated minimum central pressure is 945 mb (27.91 inches).


HAZARDS AFFECTING LAND
----------------------
STORM SURGE:  The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline.  The water has the
potential to reach the following heights above ground if peak surge
occurs at the time of high tide...

Cape Fear to Cape Lookout, including the Neuse and Pamlico
Rivers...9-13 ft
North Myrtle Beach to Cape Fear...6-9 ft
Cape Lookout to Ocracoke Inlet...6-9 ft
South Santee River to North Myrtle Beach...4-6 ft
Ocracoke Inlet to North Carolina/Virginia Border...4-6 ft
Edisto Beach to South Santee River...2-4 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive waves.  Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances.  For information specific to your area, please see
products issued by your local National Weather Service forecast
office.

RAINFALL: Florence is expected to produce total rainfall
accumulations of 15 to 25 inches with isolated maximum amounts of
35 inches near the storm's track over portions of the Carolinas and
Mid-Atlantic States from late this week into early next week. This
rainfall would produce catastrophic flash flooding and significant
river flooding.

WIND:  Hurricane conditions are expected to reach the coast within
the hurricane warning area on Friday.  Winds are expected to first
reach tropical storm strength on Thursday, making outside
preparations difficult or dangerous.  Preparations to protect life
and property should be rushed to completion.

SURF:  Swells generated by Florence are affecting Bermuda and
portions of the U.S. East Coast.  These swells are likely to cause
life-threatening surf and rip current conditions.  Please consult
products from your local weather office.


NEXT ADVISORY
-------------
Next intermediate advisory at 800 PM AST.
Next complete advisory at 1100 PM AST.

$$
Forecaster Stewart

Code: Select all

Hurricane Florence Discussion Number  50
NWS National Hurricane Center Miami FL       AL062018
500 PM AST Tue Sep 11 2018

Microwave satellite data indicate that Florence completed a full
eyewall replacement cycle (ERC) a few hours ago, and recent visible
and infrared imagery suggests that the eye has contracted slightly.
Outflow continues to expand in all quadrants, and the outflow jets
to the northwest and east have become better defined. Satellite
intensity estimates from TAFB, SAB, and UW-CIMSS ADT are all
T6.0/115 kt, and recent NHC objective intensity estimates are
T6.2/120 kt. Given that the eye has mostly cleared out and has also
warmed to near 19 deg C, the initial intensity has been bumped
upward to 120 kt, which could be conservative. All of the wind radii
had to be expanded/increased based on a blend of the earlier
reconnaissance data and a 1430 UTC ASCAT scatterometer pass.

The initial motion estimate is now 300/15 kt. There remains no
significant to the previous track forecast or reasoning. Overall,
the global and regional models have done a good job capturing the
evolving synoptic- scale flow pattern across CONUS, with an
amplifying trough moving onshore the the northwestern U.S. coast,
which is inducing downstream ridging across the northeastern U.S.
and the northwestern Atlantic Ocean. Water vapor imagery indicates
that the blocking high pressure northwest of Bermuda is continuing
to build and shift slowly eastward. The 12Z GFS model made a
significant shift to the west, the UKMET made a shift to the east,
and the ECMWF track has remained basically unchanged through 72
hours. As a result the consensus models have made only minor track
shifts to the west. What is noticeable is that all of the global and
regional models are indicating that the steering currents will
collapse by 72 h when Florence is approaching the southeast U.S.
coast. The weak steering currents are expected to continue through
the weekend, which makes the forecast track on days 3-5 quite
uncertain. The latest NHC forecast track is very similar to the
previous two advisory tracks, and lies the middle of the guidance
envelope between the consensus models TVCA to the north and the HCCA
and FSSE models to the south.

During the next 24 hours or so, Florence is expected to remain in a
very favorable environment consisting of low shear near 5 kt, an
expanding upper-level outflow pattern, and above-average SSTs of
29.0-29.5 deg C, which should result in additional strengthening.
By 48 h, the decreasing forward speed along with the large
inner-core wind field should induce some upwelling and gradual
weakening. Although the GFS- and ECMWF-based SHIPS intensity models
are indicating an increase in the southwesterly shear to near 20 kt,
this could be due to the SHIPS model capturing Florence's own
strong outflow from the GFS and ECMWF model fields. Despite the
weakening shown at 72 hours, Florence is still expected to remain a
dangerous hurricane through landfall. After Florence moves inland,
the slow forward speed of less than 5 kt should cause a rapid spin
down and weakening of the hurricane's circulation. The new NHC
intensity forecast is a little above the highest guidance based on
the aforementioned very favorable synoptic outflow pattern, and to
maintain continuity with the previous forecast.

Key Messages:

1. A life-threatening storm surge is now highly likely along
portions of the coastlines of South Carolina and North Carolina, and
a Storm Surge Warning is in effect for a portion of this area. All
interests from South Carolina into the mid-Atlantic region should
ensure they have their hurricane plan in place and follow any advice
given by local officials.

2. Life-threatening, catastrophic flash flooding and significant
river flooding is likely over portions of the Carolinas and
Mid-Atlantic states from late this week into early next week, as
Florence is expected to slow down as it approaches the coast and
moves inland.

3. Damaging hurricane-force winds are likely along portions of the
coasts of South Carolina and North Carolina, and a Hurricane Warning
has been issued for a part of this area.  Damaging winds could also
spread well inland into portions of the Carolinas and Virginia.

4. Large swells affecting Bermuda and portions of the U.S. East
Coast will continue this week, resulting in life-threatening surf
and rip currents.

FORECAST POSITIONS AND MAX WINDS

INIT  11/2100Z 27.5N  67.1W  120 KT 140 MPH
 12H  12/0600Z 28.7N  69.3W  130 KT 150 MPH
 24H  12/1800Z 30.4N  72.1W  135 KT 155 MPH
 36H  13/0600Z 32.1N  74.5W  130 KT 150 MPH
 48H  13/1800Z 33.4N  76.2W  120 KT 140 MPH
 72H  14/1800Z 34.5N  77.7W  100 KT 115 MPH...NEAR THE COAST
 96H  15/1800Z 35.0N  78.8W   40 KT  45 MPH...INLAND
120H  16/1800Z 35.7N  81.7W   25 KT  30 MPH...INLAND

$$
Forecaster Stewart
BlueJay
Posts: 938
Joined: Tue Mar 04, 2014 10:47 am
Location: Alden Bridge-The Woodlands, Texas
Contact:

My cousin is a resident of Wilmington NC. She is a recent transplant from Wisconsin. She advised our family earlier today that she now knows that Florence is serious because Walmart will be closed today at 6 pm until further notice. I hope my cousin and everyone has taken this storm seriously and has/is prepared the best possible.

God speed to all of those who are faced with dealing with Florence.
unome
Posts: 3059
Joined: Fri Feb 12, 2010 6:11 pm

https://www.nhc.noaa.gov/#Florence

Code: Select all

BULLETIN
Hurricane Florence Intermediate Advisory Number 50A
NWS National Hurricane Center Miami FL       AL062018
800 PM AST Tue Sep 11 2018

...DANGEROUS FLORENCE HEADED FOR THE U.S. EAST COAST...
...EXPECTED TO BRING LIFE-THREATENING STORM SURGE AND RAINFALL TO
PORTIONS OF THE CAROLINAS AND MID-ATLANTIC STATES...


SUMMARY OF 800 PM AST...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...28.0N 67.9W
ABOUT 350 MI...565 KM SSW OF BERMUDA
ABOUT 725 MI...1165 KM ESE OF CAPE FEAR NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...140 MPH...220 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...945 MB...27.91 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds, including the Neuse and Pamlico
Rivers

A Storm Surge Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Hurricane Warning is in effect for...
* South Santee River South Carolina to Duck North Carolina
* Albemarle and Pamlico Sounds

A Hurricane Watch is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Duck North Carolina to the North Carolina/Virginia border

A Tropical Storm Watch is in effect for...
* North of the North Carolina/Virginia border to Cape Charles Light
Virginia
* Chesapeake Bay south of New Point Comfort

Interests elsewhere in the southeastern and mid-Atlantic states
should monitor the progress of Florence.  Additional watches and
warnings may be required tonight or Wednesday.

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a
depiction of areas at risk, please see the National Weather
Service Storm Surge Watch/Warning Graphic, available at
hurricanes.gov.  This is a life-threatening situation.  Persons
located within these areas should take all necessary actions to
protect life and property from rising water and the potential for
other dangerous conditions.  Promptly follow evacuation and other
instructions from local officials.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.  A warning is typically issued
36 hours before the anticipated first occurrence of tropical-storm-
force winds, conditions that make outside preparations difficult or
dangerous.  Preparations to protect life and property should be
rushed to completion.

A Hurricane Watch means that hurricane conditions are possible
within the watch area.  A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

For storm information specific to your area, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 800 PM AST (0000 UTC), the eye of Hurricane Florence was located
by satellite near latitude 28.0 North, longitude 67.9 West.
Florence is moving toward the west-northwest near 17 mph (28 km/h).
A motion toward the west-northwest and northwest is expected through
early Thursday.  Florence is expected to slow down considerably by
late Thursday into Friday.  On the forecast track, the center of
Florence will move over the southwestern Atlantic Ocean between
Bermuda and the Bahamas through Wednesday, and approach the coast of
North Carolina or South Carolina in the hurricane warning area on
Thursday and Friday.

Maximum sustained winds are near 140 mph (220 km/h) with higher
gusts.  Florence is a category 4 hurricane on the Saffir-Simpson
Hurricane Wind Scale.  Strengthening is forecast tonight and
Wednesday.  While some weakening is expected on Thursday, Florence
is forecast to be an extremely dangerous major hurricane through
landfall.

Hurricane-force winds extend outward up to 60 miles (95 km) from
the center and tropical-storm-force winds extend outward up to 175
miles (280 km).

The estimated minimum central pressure is 945 mb (27.91 inches).


HAZARDS AFFECTING LAND
----------------------
STORM SURGE:  The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline.  The water has the
potential to reach the following heights above ground if peak surge
occurs at the time of high tide...

Cape Fear to Cape Lookout, including the Neuse and Pamlico
Rivers...9-13 ft
North Myrtle Beach to Cape Fear...6-9 ft
Cape Lookout to Ocracoke Inlet...6-9 ft
South Santee River to North Myrtle Beach...4-6 ft
Ocracoke Inlet to North Carolina/Virginia Border...4-6 ft
Edisto Beach to South Santee River...2-4 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large and
destructive waves.  Surge-related flooding depends on the relative
timing of the surge and the tidal cycle, and can vary greatly over
short distances.  For information specific to your area, please see
products issued by your local National Weather Service forecast
office.

RAINFALL: Florence is expected to produce total rainfall
accumulations of 15 to 25 inches with isolated maximum amounts of
35 inches near the storm's track over portions of the Carolinas and
Mid-Atlantic States from late this week into early next week.  This
rainfall would produce catastrophic flash flooding and significant
river flooding.

WIND:  Hurricane conditions are expected to reach the coast within
the hurricane warning area on Friday.  Winds are expected to first
reach tropical storm strength on Thursday, making outside
preparations difficult or dangerous.  Preparations to protect life
and property should be rushed to completion.

SURF:  Swells generated by Florence are affecting Bermuda and
portions of the U.S. East Coast.  These swells are likely to cause
life-threatening surf and rip current conditions.  Please consult
products from your local weather office.


NEXT ADVISORY
-------------
Next complete advisory at 1100 PM AST.

$$
Forecaster Pasch
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