Tuesday, August 29, 2023

Hurricane Idalia Continuing to Strengthen, Near Landfall



The storm surge with this could be insane, and the latest forecast of wind speeds is now up to 115 knots, 130 miles per hour, which would make it a "Category Four" hurricane, on the Saffir-Simpson Scale, where Five is the highest. Unlike tornado ratings, where wind speeds are estimated after looking at the damage, these hurricane ratings are given in real time, from actual observations of the maximum sustained winds. The people who fly into these storms sometimes seem to me like heroes. I'm sure it's a thrill too, but they sure provide us with valuable data. Even the best computer models could not forecast these things without people willing to get their hands dirty. I hope people have already evacuated for the most part. 

It seems I was not alone in my frustration at a lot of residents in the path of this hurricane shrugging off the evacuation orders. The British paper the Daily Mail wrote an article about it. Maybe some people will luck out or get to a shelter before the worst gets to them. It hasn't been even a full year since further to the South in Florida, they had to deal with Hurricane Ian. And this part of the state hasn't had a major hurricane in a long time, as Governor DeSantis pointed out. So we'll see how it goes. 


And this storm even looks impressive on radar. Notice that almost the entire west coast of Florida is under a Tornado Watch, because tornadoes can form very quickly in those spiral bands on the Eastern side of a hurricane. 



Tornadoes associated with hurricanes tend to happen fast and be short-lived. Remember that in a Tornado Warning, you need to move to a small interior room on the lowest floor of a sturdy house or other strong building that is not a mobile home. Even places that do not see hurricane impacts or flooding may have a low risk of seeing a tornado out of this, or some minor wind damage from just strong gusts out of some of these rain bands from a rather powerful hurricane. 

363 

WTNT35 KNHC 300256

TCPAT5


BULLETIN

Hurricane Idalia Advisory Number  14

NWS National Hurricane Center Miami FL       AL102023

1100 PM EDT Tue Aug 29 2023


...IDALIA STILL STRENGTHENING...

...FORECAST TO BE AN EXTREMELY DANGEROUS CATEGORY 4 INTENSITY AT 

LANDFALL...



SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION

-----------------------------------------------

LOCATION...27.7N 84.5W

ABOUT 125 MI...200 KM W OF TAMPA FLORIDA

ABOUT 185 MI...300 KM S OF TALLAHASSEE FLORIDA

MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H

PRESENT MOVEMENT...N OR 10 DEGREES AT 18 MPH...30 KM/H

MINIMUM CENTRAL PRESSURE...958 MB...28.29 INCHES



WATCHES AND WARNINGS

--------------------

CHANGES WITH THIS ADVISORY:


The Tropical Storm Warning for the Dry Tortugas is discontinued,

and the Tropical Storm Watch for the Lower Florida Keys is 

discontinued.


SUMMARY OF WATCHES AND WARNINGS IN EFFECT:


A Storm Surge Warning is in effect for...

* Englewood northward to Indian Pass, including Tampa Bay


A Hurricane Warning is in effect for...

* Middle of Longboat Key northward to Indian Pass, including Tampa

Bay


A Tropical Storm Warning is in effect for...

* Chokoloskee northward to the Middle of Longboat Key

* West of Indian Pass to Mexico Beach

* Sebastian Inlet Florida to Surf City North Carolina


A Storm Surge Watch is in effect for...

* Bonita Beach northward to Englewood, including Charlotte Harbour

* Mouth of the St. Mary's River to South Santee River South

Carolina

* Beaufort Inlet to Drum Inlet North Carolina

* Neuse and Pamlico Rivers North Carolina


A Hurricane Watch is in effect for...

* Mouth of the St. Mary's River to Edisto Beach South Carolina


A Tropical Storm Watch is in effect for...

* North of Surf City North Carolina to the North Carolina/Virginia

border

* Pamlico and Albemarle Sounds


A Hurricane Warning means that hurricane conditions are expected

somewhere within the warning area. Preparations to protect life

and property should be rushed to completion.


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 Tropical Storm Warning means that tropical storm conditions are

expected somewhere within the warning area.


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.

For a depiction of areas at risk, please see the National Weather

Service Storm Surge Watch/Warning Graphic, available at

hurricanes.gov.


A Hurricane Watch means that hurricane conditions are possible

within the watch area.


A Tropical Storm Watch means that tropical storm conditions are

possible within the watch area, generally within 48 hours.


Additional warnings will likely be required tonight or on Wednesday.


For storm information specific to your area in the United

States, including possible inland watches and warnings, please

monitor products issued by your local National Weather Service

forecast office.



DISCUSSION AND OUTLOOK

----------------------

At 1100 PM EDT (0300 UTC), the center of Hurricane Idalia was

located near latitude 27.7 North, longitude 84.5 West. Idalia is

moving toward the north near 18 mph (30 km/h). A northward to

north-northeastward motion is expected through tonight, with

Idalia's center forecast to reach the Big Bend coast of Florida on

Wednesday morning. After landfall, the center of Idalia is forecast

to turn toward the northeast and east-northeast, moving near or

along the coasts of Georgia, South Carolina, and North Carolina late

Wednesday and Thursday.


Hurricane Hunter aircraft data indicate that maximum sustained 

winds are near 110 mph (175 km/h) with higher gusts. Additional 

strengthening is forecast, and Idalia is expected to become a 

major hurricane during the next few hours before it reaches the Big 

Bend coast of Florida. Idalia is likely to still be a hurricane 

while moving across southern Georgia, and possibly when it reaches 

the coast of Georgia or southern South Carolina on Wednesday.


Hurricane-force winds extend outward up to 25 miles (35 km) from the

center and tropical-storm-force winds extend outward up to 160 miles

(260 km).


The estimated minimum central pressure based on Hurricane Hunter 

aircraft observations is 958 mb (28.29 inches).



HAZARDS AFFECTING LAND

----------------------

Key messages for Idalia can be found in the Tropical Cyclone

Discussion under AWIPS header MIATCDAT5 and WMO header WTNT45 KNHC,

and on the web at hurricanes.gov/text/MIATCDAT5.shtml


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 could

reach the following heights above ground somewhere in the indicated

areas if the peak surge occurs at the time of high tide...


Wakulla/Jefferson County line, FL to Yankeetown, FL...12-16 ft

Ochlockonee River, FL to Wakulla/Jefferson County line, FL...8-12 ft

Yankeetown to Chassahowitzka, FL...7-11 ft

Chassahowitzka, FL to Anclote River, FL...6-9 ft

Carrabelle, FL to Ochlockonee River, FL...5-8 ft

Anclote River, FL to Middle of Longboat Key, FL...4-6 ft

Tampa Bay...4-6 ft

Middle of Longboat Key, FL to Englewood, FL...3-5 ft

Indian Pass, FL to Carrabelle, FL...3-5 ft

Englewood, FL to Bonita Beach, FL...2-4 ft

Charlotte Harbor...2-4 ft

Mouth of the St. Mary's River to South Santee, SC...2-4 ft

Beaufort Inlet to Drum Inlet, NC...2-4 ft

Pamlico and Neuse Rivers...2-4 ft

South of Bonita Beach to Chokoloskee, FL...1-3 ft

South Santee, SC to Beaufort Inlet, NC...1-3 ft

Drum Inlet to Duck, NC...1-3 ft

Chokoloskee, FL to East Cape Sable, FL...1-3 ft

Flagler/Volusia County Line, FL to Mouth of St. Mary's River...1-3

ft

Indian Pass to Mexico Beach...1 to 3 ft

Florida Keys...1-2 ft


The deepest water will occur along the immediate coast in areas of

onshore winds, where the surge will be accompanied by large and

dangerous 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.


WIND:  Hurricane conditions are expected within the hurricane

warning area in Florida early Wednesday morning, with tropical

storm conditions beginning within the next few hours.


Tropical storm conditions will begin within the tropical storm 

warning area along the Florida Gulf coast and the Florida west coast 

soon.


Hurricane conditions are possible within the hurricane watch area

along the coasts of Georgia and South Carolina Wednesday and

Wednesday night.


Tropical storm conditions are expected to begin on Wednesday in the

warning area along the east coast of Florida, Georgia, and South

Carolina, and spread into North Carolina Wednesday night and

Thursday.  Tropical storm conditions are possible within the watch

area in North Carolina by Thursday.


RAINFALL:  Idalia is expected to produce a swath of 4 to 8 inches of 

rainfall with isolated maxima up to 12 inches from the Florida Big 

Bend through central Georgia and South Carolina, and through eastern 

North Carolina into Thursday. These rainfall amounts will lead to 

areas of flash, urban, and moderate river flooding, with locally 

considerable impacts.


SURF:  Swells generated by Idalia are affecting the southwestern

coast of Florida and will spread northward and westward to the

north-central Gulf coast through Wednesday.  These swells are

likely to cause life-threatening surf and rip current conditions.

Please consult products from your local weather office.


TORNADOES: A few tornadoes are possible tonight from the coast of 

west-central Florida northward into the Florida Big Bend region.  

The tornado risk will shift into southeast Georgia and the coastal 

Carolinas on Wednesday.



NEXT ADVISORY

-------------

Next intermediate advisory at 200 AM EDT.

Next complete advisory at 500 AM EDT.


$$

Forecaster Pasch


571 

WTNT25 KNHC 300254

TCMAT5


HURRICANE IDALIA FORECAST/ADVISORY NUMBER  14

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL102023

0300 UTC WED AUG 30 2023


NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO

LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM).

CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE

MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP).


HURRICANE CENTER LOCATED NEAR 27.7N  84.5W AT 30/0300Z

POSITION ACCURATE WITHIN  15 NM


PRESENT MOVEMENT TOWARD THE NORTH OR  10 DEGREES AT  16 KT


ESTIMATED MINIMUM CENTRAL PRESSURE  958 MB

MAX SUSTAINED WINDS  95 KT WITH GUSTS TO 110 KT.

64 KT....... 20NE  15SE  10SW  10NW.

50 KT....... 50NE  40SE  20SW  20NW.

34 KT.......120NE 140SE  50SW  60NW.

12 FT SEAS..120NE 150SE  90SW  90NW.

WINDS AND SEAS VARY GREATLY IN EACH QUADRANT.  RADII IN NAUTICAL

MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.


REPEAT...CENTER LOCATED NEAR 27.7N  84.5W AT 30/0300Z

AT 30/0000Z CENTER WAS LOCATED NEAR 26.9N  84.7W


FORECAST VALID 30/1200Z 30.0N  83.9W...ON COAST

MAX WIND 115 KT...GUSTS 140 KT.

64 KT... 25NE  25SE  15SW  15NW.

50 KT... 50NE  50SE  25SW  25NW.

34 KT...100NE 160SE  60SW  60NW.


FORECAST VALID 31/0000Z 32.3N  81.3W...INLAND

MAX WIND  70 KT...GUSTS  85 KT.

64 KT... 15NE  15SE   0SW   0NW.

50 KT... 30NE  30SE  20SW  15NW.

34 KT... 90NE 170SE  50SW  30NW.


FORECAST VALID 31/1200Z 33.5N  78.6W...OVER WATER

MAX WIND  50 KT...GUSTS  60 KT.

50 KT... 30NE  30SE  20SW   0NW.

34 KT...110NE 160SE  80SW  30NW.


FORECAST VALID 01/0000Z 33.8N  75.0W

MAX WIND  50 KT...GUSTS  60 KT.

50 KT... 30NE  30SE  30SW   0NW.

34 KT...150NE 100SE 100SW  80NW.


FORECAST VALID 01/1200Z 33.5N  72.5W

MAX WIND  50 KT...GUSTS  60 KT.

34 KT...120NE  70SE  80SW  90NW.


FORECAST VALID 02/0000Z 32.9N  71.0W

MAX WIND  45 KT...GUSTS  55 KT.

34 KT...130NE  50SE  80SW 120NW.


EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM

ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY


OUTLOOK VALID 03/0000Z 32.0N  69.4W

MAX WIND  45 KT...GUSTS  55 KT.


OUTLOOK VALID 04/0000Z 31.0N  68.4W

MAX WIND  45 KT...GUSTS  55 KT.


REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 27.7N  84.5W


INTERMEDIATE PUBLIC ADVISORY...WTNT35 KNHC/MIATCPAT5...AT 30/0600Z


NEXT ADVISORY AT 30/0900Z


$$

FORECASTER PASCH


323 

FONT15 KNHC 300256

PWSAT5


HURRICANE IDALIA WIND SPEED PROBABILITIES NUMBER  14                

NWS NATIONAL HURRICANE CENTER MIAMI FL       AL102023               

0300 UTC WED AUG 30 2023                                            


AT 0300Z THE CENTER OF HURRICANE IDALIA WAS LOCATED NEAR LATITUDE   

27.7 NORTH...LONGITUDE 84.5 WEST WITH MAXIMUM SUSTAINED WINDS NEAR  

95 KTS...110 MPH...175 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 WED 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 WED 12Z WED 00Z THU 12Z THU 00Z FRI 00Z SAT 00Z SUN

PERIODS         TO      TO      TO      TO      TO      TO      TO  

             12Z WED 00Z THU 12Z THU 00Z FRI 00Z SAT 00Z SUN 00Z MON


FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

LOCATION       KT                                                   


WALLOPS CDA    34  X   X( X)   X( X)   1( 1)   1( 2)   X( 2)   1( 3)


OCEANA NAS VA  34  X   X( X)   1( 1)   2( 3)   2( 5)   X( 5)   X( 5)


CAPE HATTERAS  34  X   X( X)   3( 3)  15(18)   5(23)   X(23)   X(23)

CAPE HATTERAS  50  X   X( X)   X( X)   2( 2)   1( 3)   1( 4)   X( 4)


FAYETTEVILLE   34  X   1( 1)   3( 4)   X( 4)   X( 4)   X( 4)   X( 4)


CHERRY PT NC   34  X   1( 1)   2( 3)   7(10)   1(11)   X(11)   1(12)


NEW RIVER NC   34  X   1( 1)   7( 8)  22(30)   2(32)   X(32)   X(32)

NEW RIVER NC   50  X   X( X)   X( X)   4( 4)   X( 4)   X( 4)   X( 4)


MOREHEAD CITY  34  X   2( 2)   8(10)  20(30)   1(31)   X(31)   1(32)

MOREHEAD CITY  50  X   X( X)   X( X)   4( 4)   X( 4)   X( 4)   X( 4)


SURF CITY NC   34  X   2( 2)  21(23)  14(37)   1(38)   X(38)   X(38)

SURF CITY NC   50  X   X( X)   2( 2)   3( 5)   X( 5)   X( 5)   X( 5)


WILMINGTON NC  34  X   1( 1)  13(14)   6(20)   1(21)   X(21)   X(21)


BALD HEAD ISL  34  X   4( 4)  41(45)   8(53)   1(54)   X(54)   X(54)

BALD HEAD ISL  50  X   X( X)   7( 7)   3(10)   X(10)   X(10)   X(10)

BALD HEAD ISL  64  X   X( X)   1( 1)   X( 1)   X( 1)   X( 1)   X( 1)


FLORENCE SC    34  X   5( 5)  17(22)   X(22)   X(22)   X(22)   X(22)


COLUMBIA SC    34  X  14(14)   5(19)   X(19)   X(19)   X(19)   X(19)


LITTLE RIVER   34  X   7( 7)  45(52)   3(55)   X(55)   X(55)   X(55)

LITTLE RIVER   50  X   X( X)   9( 9)   1(10)   X(10)   X(10)   X(10)

LITTLE RIVER   64  X   X( X)   2( 2)   X( 2)   X( 2)   X( 2)   X( 2)


MYRTLE BEACH   34  X  12(12)  48(60)   3(63)   X(63)   X(63)   X(63)

MYRTLE BEACH   50  X   1( 1)  12(13)   1(14)   X(14)   X(14)   X(14)

MYRTLE BEACH   64  X   X( X)   2( 2)   X( 2)   X( 2)   X( 2)   X( 2)


GEORGETOWN SC  34  X  13(13)  46(59)   1(60)   X(60)   X(60)   X(60)

GEORGETOWN SC  50  X   X( X)   6( 6)   X( 6)   X( 6)   X( 6)   X( 6)


CHARLESTON SC  34  1  70(71)  17(88)   1(89)   X(89)   X(89)   X(89)

CHARLESTON SC  50  X  11(11)  31(42)   X(42)   X(42)   X(42)   X(42)

CHARLESTON SC  64  X   1( 1)   7( 8)   X( 8)   X( 8)   X( 8)   X( 8)


BEAUFORT MCAS  34  2  89(91)   4(95)   X(95)   X(95)   X(95)   X(95)

BEAUFORT MCAS  50  X  48(48)  15(63)   X(63)   X(63)   X(63)   X(63)

BEAUFORT MCAS  64  X  11(11)   6(17)   X(17)   X(17)   X(17)   X(17)


AUGUSTA GA     34  1  27(28)   X(28)   X(28)   X(28)   X(28)   X(28)


SAVANNAH GA    34  1  93(94)   1(95)   X(95)   X(95)   X(95)   X(95)

SAVANNAH GA    50  X  48(48)   2(50)   X(50)   X(50)   X(50)   X(50)

SAVANNAH GA    64  X   4( 4)   X( 4)   X( 4)   X( 4)   X( 4)   X( 4)


KINGS BAY GA   34 34  64(98)   X(98)   X(98)   X(98)   X(98)   X(98)

KINGS BAY GA   50  1  32(33)   X(33)   X(33)   X(33)   X(33)   X(33)

KINGS BAY GA   64  X   6( 6)   X( 6)   X( 6)   X( 6)   X( 6)   X( 6)


WAYCROSS GA    34 48  51(99)   X(99)   X(99)   X(99)   X(99)   X(99)

WAYCROSS GA    50  1  73(74)   X(74)   X(74)   X(74)   X(74)   X(74)

WAYCROSS GA    64  X  28(28)   X(28)   X(28)   X(28)   X(28)   X(28)


MAYPORT NS FL  34 32  64(96)   X(96)   X(96)   X(96)   X(96)   X(96)

MAYPORT NS FL  50  1  13(14)   X(14)   X(14)   X(14)   X(14)   X(14)

MAYPORT NS FL  64  X   2( 2)   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)


JACKSONVILLE   34 37  59(96)   X(96)   X(96)   X(96)   X(96)   X(96)

JACKSONVILLE   50  X  13(13)   X(13)   X(13)   X(13)   X(13)   X(13)

JACKSONVILLE   64  X   2( 2)   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)


GAINESVILLE FL 34 86  11(97)   X(97)   X(97)   X(97)   X(97)   X(97)

GAINESVILLE FL 50  3   2( 5)   X( 5)   X( 5)   X( 5)   X( 5)   X( 5)


DAYTONA BEACH  34  7   5(12)   X(12)   X(12)   X(12)   X(12)   X(12)


THE VILLAGES   34 42   4(46)   X(46)   X(46)   X(46)   X(46)   X(46)


ORLANDO FL     34  4   1( 5)   X( 5)   X( 5)   X( 5)   X( 5)   X( 5)


COCOA BEACH FL 34  2   2( 4)   1( 5)   X( 5)   X( 5)   X( 5)   X( 5)


PATRICK AFB    34  2   2( 4)   1( 5)   X( 5)   X( 5)   X( 5)   X( 5)


FT PIERCE FL   34  2   1( 3)   X( 3)   X( 3)   X( 3)   X( 3)   X( 3)


VENICE FL      34 64   X(64)   X(64)   X(64)   X(64)   X(64)   X(64)


TAMPA FL       34 92   X(92)   X(92)   X(92)   X(92)   X(92)   X(92)


CEDAR KEY FL   34 99   X(99)   X(99)   X(99)   X(99)   X(99)   X(99)

CEDAR KEY FL   50 21   X(21)   X(21)   X(21)   X(21)   X(21)   X(21)

CEDAR KEY FL   64  2   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)


TALLAHASSEE FL 34 91   1(92)   X(92)   X(92)   X(92)   X(92)   X(92)

TALLAHASSEE FL 50 36   2(38)   X(38)   X(38)   X(38)   X(38)   X(38)

TALLAHASSEE FL 64 13   5(18)   X(18)   X(18)   X(18)   X(18)   X(18)


ST MARKS FL    34 98   X(98)   X(98)   X(98)   X(98)   X(98)   X(98)

ST MARKS FL    50 58   2(60)   X(60)   X(60)   X(60)   X(60)   X(60)

ST MARKS FL    64 33   1(34)   X(34)   X(34)   X(34)   X(34)   X(34)


APALACHICOLA   34 77   X(77)   X(77)   X(77)   X(77)   X(77)   X(77)

APALACHICOLA   50 12   X(12)   X(12)   X(12)   X(12)   X(12)   X(12)

APALACHICOLA   64  3   X( 3)   X( 3)   X( 3)   X( 3)   X( 3)   X( 3)


GFMX 290N 850W 34 94   X(94)   X(94)   X(94)   X(94)   X(94)   X(94)

GFMX 290N 850W 50 12   X(12)   X(12)   X(12)   X(12)   X(12)   X(12)

GFMX 290N 850W 64  2   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)   X( 2)


PANAMA CITY FL 34 18   2(20)   X(20)   X(20)   X(20)   X(20)   X(20)


BERMUDA        34  X   X( X)   X( X)   X( X)   1( 1)   4( 5)   4( 9)


$$                                                                  

FORECASTER PASCH                                                    


000

WTNT45 KNHC 300259

TCDAT5


Hurricane Idalia Discussion Number  14

NWS National Hurricane Center Miami FL       AL102023

1100 PM EDT Tue Aug 29 2023


Satellite and NWS radar imagery show that Idalia is becoming 

increasingly more organized.  The eye on the Tampa WSR-88D is 

becoming better defined and the cloud pattern on GOES 16 imagery 

consists of a growing Central Dense Overcast with a strong 

convective band over the eastern semicircle of the circulation.  

Reconnaissance aircraft measurements show that the central pressure 

is steadily falling and is now around 958 mb.  Flight-level and 

SFMR-observed winds along with Doppler velocity data from the 

aircraft support an intensity of 95 kt for this advisory.


Idalia is now moving faster toward the north or slightly east of 

north with a motion estimate of 010/16 kt. The hurricane is moving 

between a mid-level trough over the northwestern Gulf of Mexico and 

ridge over the Bahamas and Greater Antilles.  The system is expected 

to turn north-northeastward within the next 12 hours, make landfall 

along the northeastern Gulf coast, and then move northeastward to 

eastward on the southern side of a mid-level trough moving off the 

northeast U.S. coast.  The 12-hour track forecast point for this 

advisory has been nudged a bit westward, a little west of the model 

consensus, but close to the latest GFS and ECMWF solutions.  It 

should be noted that some credible models, i.e. the HAFS-A and 

HAFS-B predictions, are even a little father west.


After landfall, Idalia is expected to move near or along the coast 

of Georgia and the Carolinas in 24-36 hours.  Uncertainty in the 

track forecast beyond 48 hours remains quite large, with some of 

the global models turning Idalia southward, while some of the 

regional hurricane models show the storm moving out to sea.  Given 

the uncertainties, the official track forecast shows a slow 

southeastward motion in 4 to 5 days.


Based on the current strengthening trend and the favorable 

thermodynamic and oceanic conditions, significant strengthening 

seems likely up to landfall.  The new official intensity forecast 

calls for Idalia to reach category 4 strength at landfall.  This is 

fairly close to the HAFS And HWRF regional hurricane model 

simulations.  After the center moves back over the Atlantic, 

significant restrengthening is not anticipated at this time due to 

the expectation of strong vertical west-southwesterly vertical wind 

shear.


Dangerous winds are likely to spread well inland near the path of 

Idalia due to its relatively fast forward motion.



KEY MESSAGES:


1. Catastrophic impacts from storm surge inundation of 12 to 16 feet 

above ground level and destructive waves are expected somewhere 

between the Wakulla/Jefferson County line and Yankeetown, Florida. 

Life-threatening storm surge inundation is likely elsewhere along 

portions of the Florida Gulf Coast where a Storm Surge Warning is in 

effect. Residents in these areas should follow any advice given by 

local officials.


2. There is the potential for destructive life-threatening winds

where the core of Idalia moves onshore in the Big Bend region of

Florida, with hurricane conditions expected elsewhere in portions of

the Hurricane Warning area along the Florida Gulf Coast. Strong

winds will also spread inland across portions of northern Florida

and southern Georgia near the track of the center of Idalia where

Hurricane Warnings are in effect. Residents in these areas should be

prepared for long-duration power outages. Damaging hurricane-force

winds are possible in portions of eastern Georgia and southeastern

South Carolina where Hurricane Watches are in effect.


3. Areas of flash, urban, and moderate river flooding, with locally

considerable impacts, are expected across the Florida Big Bend,

central Georgia and South Carolina, through eastern North Carolina

into Thursday.



FORECAST POSITIONS AND MAX WINDS


INIT  30/0300Z 27.7N  84.5W   95 KT 110 MPH

 12H  30/1200Z 30.0N  83.9W  115 KT 130 MPH...ON COAST

 24H  31/0000Z 32.3N  81.3W   70 KT  80 MPH...INLAND

 36H  31/1200Z 33.5N  78.6W   50 KT  60 MPH...OVER WATER

 48H  01/0000Z 33.8N  75.0W   50 KT  60 MPH

 60H  01/1200Z 33.5N  72.5W   50 KT  60 MPH

 72H  02/0000Z 32.9N  71.0W   45 KT  50 MPH

 96H  03/0000Z 32.0N  69.4W   45 KT  50 MPH

120H  04/0000Z 31.0N  68.4W   45 KT  50 MPH


$$

Forecaster Pasch

No comments:

Post a Comment