Friday, October 7, 2016

Hurricane Matthew Hugging the Coast near Southeast Georgia; Life-Threatening Flooding Imminent in Savannah, Georgia, and Charleston, South Carolina

October 7,2016
Hurricane Matthew's eyewall continues to brush parts of Georgia's southeast coast with high winds and major storm surge flooding and will spread those impacts, in addition to potentially serious rainfall flooding, into Georgia, South Carolina and southern North Carolina through at least Saturday night.
(MORE: WATCH OUR CONTINUOUS LIVE COVERAGE ON THE WEATHER CHANNEL)
Hurricane warnings are in effect north of the Flagler/Volusia county line in Florida to Surf City, North Carolina. This includes locations such as Jacksonville, FloridaSavannah, GeorgiaCharleston, South Carolina, and Wilmington, North Carolina.
(MORE: Interactive Matthew Tracker Page)

Current Watches/Warnings
A hurricane watch has been posted north of Surf City to Cape Lookout, North Carolina, meaning hurricane conditions are possible within 48 hours.
A tropical storm warning has been hoisted north of there to include the Outer Banks of North Carolina, as well as Albemarle and Pamlico Sounds.
All coastal warnings have been discontinued south of the Flagler/Volusia county line in Florida.

Latest Radar, Warnings
Matthew's precarious track, in which the eyewall may scrape the coast with destructive hurricane-force winds, will spread north through Saturday along the Georgia coast and parts of the South Carolina coast.
Storm surge flooding has already occurred along the northeast Florida coast, including in the Daytona Beach, St. Augustine and Jacksonville Beach areas, and has already spread as far north as South Carolina during Friday afternoon's high tide.
During Friday evening's low tide, tides at Charleston Harbor were running about 3 feet higher than normal, which means life-threatening flooding is imminent during high tide at 12:57 a.m. Saturday.
A dangerous night is also ahead for Savannah, Georgia, as an 80+ year-old storm surge record is in jeopardy. The Weather Channel hurricane specialist Michael Lowry is afraid the worst land impacts from Matthew will occur with early Saturday's high tide in Savannah, due to it occurring at night with a lot of the city without power.
According to the National Weather Service (NWS) in Jacksonville, Florida, Friday morning, "Barrier islands are likely to be breached and it is extremely possible that new inlets will be cut off in the worst affected areas." The NWS office in Charleston, South Carolina, said Friday that tide levels at both Charleston, South Carolina, and Ft. Pulaski, Georgia, could approach or even surpass those seen during the October 2015 epic flood event.
(MORE: Hurricane Central | Interactive Storm Tracker Map)
Isolated tornadoes are also possible. A tornado watch is in effect for parts of southeast Georgia and coastal South Carolina until 12 a.m. EDT. This watch area includes Savannah, Georgia, and Charleston, South Carolina.

Latest Status and Storm Reports

Satellite and radar imagery show the eye of Matthew marching northward roughly paralleling the northeast Florida coast and southeast Georgia coast.
Matthew's tropical storm-force wind field (at least 39 mph sustained winds) extends up to 185 miles from the center, and hurricane-force winds extend up to 60 miles from the center.
The center of Matthew remained within 25-40 miles of the northeast Florida coast much of Friday, but has been close enough to bring hurricane-force wind gusts to some coastal areas.

Current Storm Status
Storm Surge Reports
Early Friday afternoon, storm surge flooding affected the St. Augustine area, including major flooding on Anastasia Island where water was reported to be 2.5 feet above ground level. To the south in nearby Flagler Beach, Florida, parts of A1A were washed out by the storm surge.
Storm surge was also seen pushing ashore in parts of Jacksonville Beach and Fernandina Beach.
Friday evening, water levels peaked around 7 feet above normal at Fernandina Beach, Florida, and about 5 feet above normal at Ft. Pulaski, Georgia, according to NOAA/National Ocean Service data. The St. Johns River in northeast Florida reached its highest level on record at Shands Bridge, along with 3 to 4.3 feet of storm surge inundation reported at the Racy Point, Red Bay Point and I-295 Bridge tide gauges.
Farther south, the storm surge peaked at roughly 4 feet at Trident Pier, near Cape Canaveral early Friday.
Wind Reports
Here are some of the top wind gust reports from Matthew, so far.
Cape Canaveral, Florida: 107 mph
Daytona Beach, Florida: 91 mph
Jacksonville Area: 87 mph
South Ponte Vedra Beach, Florida: 84 mph
Melbourne, Florida: 70 mph
Folly Beach, South Carolina: 68 mph
Tybee Island, Georgia: 64 mph
Hilton Head, South Carolina: 63 mph
Orlando Area: Gusts over 60 mph reported
Multiple roofs were damaged along the oceanfront in Flagler Beach.

Current Wind Speed and Gusts
Rainfall Reports
Bands of locally heavy rain have spread over 600 miles north of Matthew, an ominous sign for the rainfall flood potential, though no reports of flash flooding have yet been received.

Southeast Regional Radar/Alerts
A particularly solid area of heavy rain has formed to the north of Matthew, pivoting into parts of the South Carolina Lowcountry and eastern Georgia. 3 to 5+ inches of rain is possible over the next couple of hours within this rainband, from Brunswick, Georgia, to Beaufort, South, Carolina.
Here are some of the totals from Matthew 8 a.m. Thursday - 8 p.m. Friday (EDT):
McIntosh, Georgia: 10.83 inches
Orlando, Florida (Sanford): 7.93 inches
Jacksonville, Florida: 6.64 inches
Savannah, Georgia: 4.02 inches
Charleston, South Carolina: 1.00 inches

Estimated Storm-Total Rainfall, So Far

Timing For Matthew

Here is the approximate timing of the worst wind and surge impacts, coinciding with the nearest passage of the eyewall of Matthew. (Note that Matthew's eye may never make landfall, but its eyewall, containing the hurricane's strongest winds, may do so.)
  • Northeastern Florida: Into early Saturday morning
  • Georgia coast: Through Saturday morning
  • South Carolina: Saturday through Saturday evening
  • North Carolina (mainly south): Saturday afternoon through early Sunday

Projected Path and Intensity
(MORE: Facts/Myths About the Hurricane Cones of Uncertainty)
Note that there may be coastal flooding occurring well ahead of the closest approach of Matthew in Georgia and parts of the Carolinas.
Small, subtle changes in the path of the eyewall, sometimes not resolvable until hours before the passage, will make a large difference on wind impact.
(MORE: When Hurricanes Parallel the Coast Instead of Making Landfall)

Storm Surge, Battering Waves, Beach Erosion Dangers

Major, damaging storm surge flooding is expected as Matthew curls its way northward along the Southeast coast. If you live along the immediate coast and are told to evacuate, please do so.
Here is how high the water could reach during this life-threatening inundation if the peak surge coincides with high tide, according to the National Hurricane Center:
  • Flagler Beach, Florida, to Edisto Beach, South Carolina: 6 to 9 feet above ground level
  • Edisto Beach, South Carolina, to Cape Fear, North Carolina: 5 to 7 feet above ground level
  • Flagler/Volusia county line in Florida to Flagler Beach, Florida: 4 to 6 feet above ground level
  • Cape Fear, North Carolina, to Duck, North Carolina (including Albemarle, Pamlico Sounds): 2 to 4 feet above ground level
(MAP: NHC Prototype Storm Surge Watch/Warning)
The 6- to 9-foot above ground level forecast storm surge, mentioned above, is comparable to what New Jersey and New York experienced during Superstorm Sandy in Oct. 2012. The highest surge values there were 4 to 9 feet above ground level.
NWS Charleston warned surge levels along the South Carolina or Georgia coast could be the worst seen since 1989's Hurricane Hugo in some locations.

Storm Surge Inundation Forecast
Keep in mind the NHC surge forecasts are "worst-case scenarios" if they occur at high tide.
Here are times of the next three high and low tides for several locations that could see significant storm surge inundation.
Jacksonville Beach, Florida1:29 a.m. Sat - high7:29 a.m. Sat - low1:59 p.m. Sat - high
St. Simons Island, Georgia1:28 a.m. Sat - high7:28 a.m. Sat - low1:50 p.m. Sat - high
Hilton Head Island, South Carolina1:56 a.m. Sat - high7:46 a.m. Sat - low2:28 p.m. Sat - high
Charleston, South Carolina12:57 a.m. Sat - high7:04 a.m. Sat - low1:39 p.m. Sat - high
Myrtle Beach, South Carolina12:40 a.m. Sat - high6:43 a.m. Sat - low1:24 p.m. Sat - high
The NWS-Charleston office warned Friday morning that persistent northeast winds ahead of Matthew had already raised tide levels, prompting concern that tides for early Saturday morning's high tide could reach the second-highest level on record at Ft. Pulaski, Georgia, cutting off Tybee Island from Savannah. This could also be a top-5 or top-10 highest tide level on record in Charleston, South Carolina, according to the NWS.
Tides at Fort Pulaski, GA running ~5 ft higher than normal AT LOW TIDE!! Life-threatening flooding during high tide around 1 AM!!

Matthew will also continue to generate large, battering waves along the entire coastline of the Southeast through this weekend. Mariners should stay out of the water given this danger.

Current Wave Heights From Matthew
Of course, major beach erosion is a given with all those factors above playing out.

Damaging Hurricane-Force Winds Possible


Hourly Wind Gust Forecast
Matthew's eyewall will roughly parallel the northeast Florida, Georgia and South Carolina coasts, in what is an extremely difficult forecast for peak wind impact.
The National Hurricane Center put the crux of this challenge best:
With that in mind, wind gusts capable of downing trees, at least some structural damage, and power outages are likely from Matthew from northeastern Florida to at least the Lowcountry of South Carolina and perhaps southern North Carolina.
However, if the eyewall happens to wobble just enough closer to shore, more destructive winds over 80 mph may lead to more structural damage and more widespread power outages in these areas.
The potential for tropical storm-force winds (39-plus mph) will encompass a larger part of Florida as well as southeast Georgia and the coastal Carolinas.
(MORE: Impact Differences When a Hurricane Parallels the Coast Instead of Making Landfall)
Even tropical storm-force winds could down trees or tree limbs and knock out power.

Hurricane-Force Wind Probabilities

Rainfall Flooding, Tornadoes

Over a foot of total rain may fall over parts of the coastal plain of the Carolinas. A broad swath of 5 inches or more will occur from northeast Florida to eastern North Carolina.

Rainfall Forecast
In addition to the rainfall flood potential from this, storm surge flooding will also limit the ability of swollen rivers to drain, backing up these rivers potentially miles inland.
This combination is expected to produce major flooding in places like Charleston, South Carolina, where flooding there could be comparable to what was seen in the city during the October 2015 event, according to the National Weather Service.
An isolated tornado threat could also develop on the Southeast coast, as well, if any discrete cells form in outer rainbands of Matthew.

Matthew's Strange Future Next Week

You may have noticed the forecast track has changed radically for areas from North Carolina northward.
Matthew will not get "picked up" by a southward dip in the jet stream forecast to push into the Northeast U.S. this weekend.
Instead, Matthew is expected to curl southeast, then south away from the coastal Carolinas beginning later Sunday.
Matthew is then expected to meander off the Southeast coast or near the Bahamas into next week, but details on where it may eventually go, including perhaps a second strike as a weaker system in the Bahamas or Florida, are uncertain at this time.
(MORE: Matthew May Look Back Toward Florida, Bahamas for Second Hit)

Caribbean and Bahamas Storm Reports, Recap

George F.L. Charles Airport on St. Lucia picked up 9.21 inches of rain Wednesday. On the south side of the island, Hewanorra Int'l Airport picked up 13.19 inches of rain in just 12 hours from 8 p.m. Wednesday through 8 a.m. Thursday, according to the Antigua Met Service.
A wind gust to 89 mph was reported in St. Pierre, Martinique, Wednesday evening. Some stations are elevated at 50 to 100 feet. Sustained winds of 39 mph were reported on the island of Barbados.
Matthew strengthened to a rare Category 5 late Friday evening, becoming the first Category 5 Atlantic basin hurricane since Hurricane Felix in early September 2007.
(MORE: Category 5 Hurricanes Prior to Matthew)
Hurricane Matthew became the fifth hurricane of the 2016 Atlantic hurricane season early Thursday afternoon.
According to Colorado State University tropical scientist Dr. Phil Klotzbach, Matthew became the lowest latitude Category 5 hurricane in the Atlantic on record (beating the old record set by Ivan in 2004).
Some outer rainbands triggered flash flooding in Jamaica Sunday, hundreds of miles away from the center of Matthew.
Interestingly Sunday night, a fortunately-placed NOAA buoy sampled Matthew's eye, providing valuable information for meteorologists.
Hurricane Matthew's eye first came ashore in the Greater Antilles in the western Tiburon Peninsula of Haiti near the town of Les Anglais around 7 a.m. EDT Tuesday morning, according to the National Hurricane Center.
Matthew was the first Category 4 Haiti landfall since Hurricane Cleo in 1964, and only the fourth such intensity or stronger hurricane to track within 65 nautical miles of southern Haiti's Tiburon Peninsula since the 1960s, according to NOAA's Best Tracks Database.
(MORE: Devastation in Haiti)
Hurricane Matthew made a second landfall near Juaco, Cuba, around 8 p.m. EDT Tuesday evening. October 4. An unconfirmed wind gusts to 155 mph was reported in the town of Baracoa, Cuba, in Matthew's eyewall.
Radar from Guantanamo Bay Wednesday morning indicated Matthew's eyewall had a sizable hole in its western side after passing over Cuba Tuesday night.
After passing Cuba, Matthew passed through the Bahamas.
Wednesday night, a 119 mph sustained wind was clocked at Exuma International Airport. Sustained winds over 100 mph were also clocked at George Town, also on Exuma.
Winds gusted to 85 mph in Nassau Thursday.
Remarkable observation tonight from GGT Airport as rakes the Bahamas

Radar indicates that Matthew made landfall along the western tip of Grand Bahama Island prior to 8 p.m. EDT with extremely high winds battering that island in the eyewall.
In the 9 p.m. hour on October 6, Grand Bahama reported a sustained wind of 64 mph.
Early Thursday evening, Freeport in the northwest Bahamas reported sustained winds of 100 mph with gusts up to 121 mph as the northern eyewall lashed the area.
In the Bahamas, Settlement Point reported sustained winds of 79 mph and gusts as high as 105 mph.

MORE: Hurricane Matthew Photos

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