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Matthew Toys With Florida Coast; Major Surge Threat Remains

By: Bob Henson 5:49 AM GMT on October 07, 2016

After barreling across the Caribbean and through the Bahamas, Hurricane Matthew backed off from an immediate U.S. landfall on Thursday night, and odds were rising that the system might not come fully ashore before looping out to sea over the weekend. In its 11 pm EDT advisory, the National Hurricane Center kept Matthew’s top sustained winds at 130 mph, making it a minimal Category 4 storm. Hurricane Hunters found that Matthew’s central pressure had dropped to 937 millibars on Wednesday night. Together with radiometer-derived surface winds of 125 mph, it was clear that Matthew remained a potent hurricane, despite its somewhat disheveled appearance on satellite. Update: At 2:00 am EDT Friday, NHC downgraded Matthew to a Category 3 storm, with top sustained winds of 120 mph.


Figure 1. Enhanced infrared satellite image of Hurricane Matthew as of 12:45 am EDT Friday, October 7, 2016. Image credit: NOAA/NESDIS.


Figure 2. WU depiction of NEXRAD radar from 1:15 am EDT Friday, October 7, 2016. The predominant outer eyewall and its intense thunderstorms (yellow band just east of Port Saint Lucie) was slowly edging toward the Florida coast.

Eyewall to eyewall
Over the course of Thursday afternoon and evening, Matthew ended up with dual, concentric eyewalls--an outer one, about 70 miles wide, and an inner one, about 10 miles wide, where the strongest winds were focused. The development of dual eyewalls often heralds an eyewall replacement cycle (ERC), in which the inner eyewall collapses and the outer one gradually contracts. Matthew appeared ripe for an ERC on Thursday evening, and that process appeared to be underway late Thursday night, as a reconnaissance summary at 12:15 am EDT Friday reported a single closed eyewall, about 55 miles wide.


Figure 3. Observations gathered by a Hurricane Hunter flight through Matthew late Wednesday night into early Thursday morning. The emergence of a single large eyewall can be seen in the extended period between wind peaks (blue trace) at around 0342Z (11:42 pm EDT Wednesday) when the aircraft detected very low surface air pressures below 945 millibars (red trace, corresponding to the pressure legend at left). Image credit: tropicaltidbits.com.


Figure 4. Official NHC forecast for Matthew as of 11 pm EDT Thursday, October 6, 2016. The unusual look of the “cone” is because of the nearly complete loop that Matthew is predicted to carve out in the next five days.

A coast-scraping track that could still cause major trouble
What was always recognized as a possibility--that Matthew would never quite make landfall on the Florida coast--emerged as the most likely outcome on Thursday night, as reflected in the 11 pm NHC outlook (see Figure 4 above). Matthew’s track out of the Bahamas was angled just far enough north of northwest to keep the center rolling more or less parallel to the Florida coast. Provided that Matthew carries out the gradual curve to the right expected late Friday through Saturday, its center will likely remain between about 20 and 50 miles off the coast, perhaps all the way to Charleston, SC, by Saturday night. This path would be enough to keep Matthew’s inner core and its top sustained winds offshore, which is very good news in terms of limiting the most severe wind damage. On the down side, Matthew’s outer eyewall--which will likely be packing streaks of 60 to 90 mph sustained winds--will probably edge onto or just inland from the coast early Friday. If Matthew’s center remains offshore as the hurricane churns north and northeast toward Georgia, then its outer eyewall may be slower to weaken. People along the Florida coast from around Melbourne northward can expect several hours of high wind on Friday, fierce enough at times to topple trees and power lines. If not catastrophic (thankfully!), such damage may end up being far more widespread on this type of coast-scraping path than it would have been with a hurricane slamming onshore at a right angle.

Hurricane-force winds are possible as far north as coastal Georgia and southern South Carolina later on Friday, but the primary threat here will be high water--the most deadly aspect of U.S. hurricanes. Because of the gradual expansion of Matthew’s wind field, its direction of motion, and the largely concave geometry of the coastline, barrier islands and inlets from north FL to southern SC remain at risk of major storm surge even if Matthew remains offshore. Late Thursday night, NHC was projecting the potential for coastal inundations of 7 to 11 feet from Sebastian Inlet, Florida, to Edisto Beach, South Carolina, including parts of the St. Johns River between the coast and Jacksonville. Breaking waves of up to 20 - 25 feet are possible atop the coastal surge.

Time and again in recent years, we’ve seen hurricanes weaken in terms of peak winds as they approach the coast, yet push far more water onshore than residents expected. This is one reason why the Saffir-Simpson scale no longer directly relates its strength categories to storm surge: peak winds near the center are an unreliable index to how much surge a hurricane may actually produce. Even if Matthew weakens and stays offshore as projected, surge levels in some areas (especially far north Florida and Georgia) may be the highest observed in many decades, and I fear that many coastal residents will underestimate this risk.


Figure 5. Projected 3-day rainfall totals from 8:00 pm EDT Thursday, October 6, to 8:00 pm Sunday, October 9. Image credit: NOAA/NWS Weather Prediction Center.

Very heavy rainfall is the other water-related threat that still looms large with Matthew. Widespread totals in the 10” to 15” range are projected to fall within about 50 miles of the coast from far north Florida to southeast North Carolina (see Figure 5). The southeast half of the Carolinas can expect 3” to 10” amounts. This may be enough to cause extensive flooding, especially where 10” - 15” of rain has fallen in the last three weeks. With winds potentially gusting to 40 - 50 mph, we can expect extensive tree loss and power outages.

If Matthew fails to make landfall on Friday, or if it does come ashore below Category 3 strength, the remarkable and unprecedented U.S. “drought” in major hurricane landfalls will continue. The last hurricane to strike the U.S. with Category 3 winds was Wilma, in October 2005--nearly 11 years ago.

Beyond the Carolinas
Long-range models agree in turning Matthew gradually seaward from the Carolinas over the weekend, and it now appears that the wacky loop-de-loop solution presented by the models a couple of days ago will materialize, at least in some form or fashion. The path shown in Figure 3 above is one of the most precise and elegant circles I’ve ever seen in a five-day NHC forecast. By Tuesday, Matthew is predicted to be heading southwestward, back into the northern Bahamas. Matthew will almost certainly be a far weaker system by this point--most likely a tropical storm. It’s certainly possible that Matthew will end up crossing Florida at some point next week.


Figure 6. Enhanced infrared satellite image of Hurricane Nicole as of 12:45 am EDT Friday, October 7, 2016. Image credit: NOAA/NESDIS.

Nicole is now a Category 2 hurricane
Quietly gathering strength while Matthew hogged the spotlight, Hurricane Nicole has become a respectable storm in its own right. Nicole’s top sustained winds were bumped up to 105 mph at 11 pm EDT Wednesday, making it a strong Category 2 hurricane. Located about 340 miles south of Bermuda, Nicole was stationary, embedded in weak steering currents and in no hurry to head anywhere. Matthew may draw close enough to Nicole early next week to bring the Fujiwhara effect into play, which would tend to push Nicole to the north and Matthew toward the south--consistent with the motions now expected for both systems, although larger-scale steering will probably be the main factor at work.

NHC’s Eric Blake provided an interesting climatological tidbit in his Thursday night discussion on Nicole: “This is the first time since September 10, 1964 that two Category 2 (or stronger) hurricanes have occurred simultaneously in the Atlantic basin west of 65W. Interestingly, those hurricanes in 1964, Dora and Ethel, were in similar positions as Matthew and Nicole are now.”

Jeff Masters will be back with our next update by late Friday morning.

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Ormond Beach
http://www.surfline.com/surf-report/ormond-beach- florida_5333/
Quoting 997. Patrap:

At 1200 UTC, 07 October 2016, MAJOR HURRICANE MATTHEW (AL14) was located in the North Atlantic basin at 28.9N and 80.3W. The current intensity was 105 kt and the center was moving at 12 kt at a bearing of 330 degrees. The minimum central pressure was 944 mb





So many wobbles!
Quoting 859. VirginIslandsVisitor:



Am so thankful you aren't using the original number on that song, Keeper!!



Quoting 999. EvanKisseloff:



I'm hearing water into the Castillo de San Marcos. Bad.


Ugh. I love that area.
Quoting 999. EvanKisseloff:



I'm hearing water into the Castillo de San Marcos. Bad.


Any idea on the downtown area?
1006. Patrap
Quoting 996. CybrTeddy:



Your average layman doesn't know that. When that stat gets thrown around on social media and the blog without that added context it's irresponsible.


Added zero ACE

Over 9 billion n damages incurred.


Stats don't mean jack squat to those impacted.

Woe is equally distributed in such a event.


1007. miamivu
Has anyone seen peak gusts so far from Matthew?
CNN reports 600K without power...Wilma caused loss of power to over 3.2 million
From NOAA's archives on Wilma:Location Instrument Peak Gust (mph)
Dry Tortugas (Keys) National Park 134
South Fork of St. Lucie River
(Martin County)
Vessel 133
Cudjoe Key Spotter 123
Fowey Rocks C-MAN 123
Palm Beach County Co-op 114
Lake Okeechobee (South end) Co-op 112
Islamorada (Keys) Co-op 110
Ochopee FCMP 109
Martin County Spotter 108
Opa Locka ASOS 105
Sombrero Key C-MAN 105
Weston FCMP 105
WFO Miami NWS 104
Palm Beach International ASOS 101
Fort Lauderdale Airport ASOS 99
Pompano Beach ASOS 98
Everglades City FCMP 94
Cape Canaveral Co-op 94
Buoy 41009 (offshore Cape
Canaveral)
Buoy 94
Miami International ASOS 92
Molasses Reef C-MAN 91
Table 1. Observed peak wind gusts in south Florida during Hurricane Wilma. Wind
measurements were taken from the Florida Coastal Monitoring Program (FCMP) wind
equipment, Automated Surface Observing Systems (ASOS), Coastal Marine Automated Network
(C-MAN) stations, National Data Buoy Center (NDBC) Data Buoys and NWS Co-op weather
observers (Co-op) and spotters.
Anyone know why the computer models stopped updating yesterday at 2 PM on the site?
1009. Smitter
Quoting 975. jlp09550:


Looks Awfully Healthy!
pt canaveral does not have a natural channel to the sea. it might take months of dredging sand so that the cruise boats can use the harbor again.
Quoting 998. DurhamWeatherLover:

Any idea on surge in St. Augustine FL?

It's really bad. Do a search of St. Augustine on Twitter and you will see tons of video clips and pics of the water going into the first story of all the businesses along the bay front. Plus there was just a report of an 83mph gust just right over the bridge in st. Augustine Beach.
1012. Patrap
Quoting 1011. TampaFLUSA:


It's really bad. Do a search of St. Augustine on Twitter and you will see tons of video clips and pics of the water going into the first story of all the businesses along the bay front. Plus there was just a report of an 83mph gust just right over the bridge in st. Augustine Beach.


Not good to hear... Thank you.
Here's a silly thought. If this were to mimic 1989. We should get one heck of a snowfall later this winter. Just sayin.
Still wobblin'.

JeffMasters has created a new entry.
1017. beell
Potential Storm Surge Flooding Map (inundation)-noaa.gov
*Displayed flooding values indicate the water height that has about a 1-in-10 (10%) chance of being exceeded.

This may be a good place to start if you're worried about surge/inundation. Zoom ALL the way in to your area of interest. Common sense, and local guidance might be a nice compliment to this as well.
Quoting 998. DurhamWeatherLover:

Any idea on surge in St. Augustine FL?


Best source I currently know of
Quoting 966. hmroe:



"silly" isn't quite the word...


Yeah. I know. It's the only one I can use in polite company and with children around while keeping my blood pressure low. :\

They are all born and raised S. Carolinians "eh we've stayed through these storm brushes before." And I'm like "Hugo wasn't a brush." "This isn't Hugo. It's not supposed to make land fall here." "Exactly! It's a different and very unique beast..."

Like they say. It only takes one storm. I hope that at the next get together they will all roll their eyes at me for the fuss I made. I will be VERY ok with that.
Wow, the pictures of St. Augustine are crazy. I hate to see it.
Reuters Top News
‏@Reuters
UPDATE: Hurricane Matthew death toll in Haiti rises to 572 - local officials. http://reut.rs/2cWWWEn
edit.
I have family in Jacksonville and it looks like they may receive worse than many others have in Florida from Matthew, the radar shows some significant rains in and yet to arrive there. They are also very low-lying. My cousins said they are taking it seriously and are prepared, which is better than the hurricane party they had during Hermine haha.

I'm sure the damage will be significant regardless.
Quoting 1005. DurhamWeatherLover:



Any idea on the downtown area?

Frequent live reports from First Coast NEws:
Link
St. Augustine and north is about to see the Western End of that Eye Wall for a a few hours. The WEW is going to skirt the coast for a while.
Looks like St Augustine & Jacksonville will catch the brunt of Matthew if the eye keeps veering west.
Quoting 965. TampaFLUSA:

I think the big story over the next couple days in the State of Florida will be the surge that is occurring right now in St. Augustine. It is unbelievable, it is going through the Castillo and through old town and rising rapidly.


There are people trapped there as we speak. I evacuated to Tallahassee, but if anyone has a truck and a boat, people there need rescuing.
Quoting 966. hmroe:



"silly" isn't quite the word...

As a senior citizen who occasionally need EMS care (for serious things) I would hate to be stuck without that access. It could be fatal. Perhaps something the stayers don't have as a factor in their lives.
1029. marsHen
noon at rocky hammock, (northeast of Cedar Key) 75F, winds 12 - 20 with bursts of gusts. drizzling. the air feels like there's a big storm nearby. just filled 11 five gal. buckets, six 2.5 gal. buckets, two 20 gal. tubs, 1 bathtub, and topped off the stock tanks. one never knows...
Quoting 1026. CentralTxDave:

Looks like St Augustine & Jacksonville will catch the brunt of Matthew if the eye keeps veering west.


Daytona Beach is getting whacked pretty bad.
If you are reading this and you are on a barrier island, or along a coastal waterway in Georgia or South Carolina. LEAVE. You have time to leave, but that is RAPIDLY running out. Just GTFO.

Ft Pulaski water level (Savannah) 45 minutes before high tide. Mathew is still 175 miles away.




1032. SLU
Quoting 992. TheInsomniac4:



Citation please. None of the data I see supports your claim.

Also, ACE is fairly noisy. Given the year-to-year variation, spotting a clear trend over a 20 year period is difficult to do, even if you happen to have knowledge of the complexity of the statistics of time series that are required to show it.


A simple Google search would lead you to the data you are requesting:


1033. SLU
Quoting 996. CybrTeddy:



Your average layman doesn't know that. When that stat gets thrown around on social media and the blog without that added context it's irresponsible, especially when an active major hurricane is impacting the Florida coastline right this very second.


I agree. That's where the mainstream media needs to be more responsible when they quote raw meteorological statistics to the general public.
Ryan Maue ‏@RyanMaue 1 minHá 1 minuto
Part of eyewall over Daytona Beach now. #Matthew
Quoting 1029. marsHen:

noon at rocky hammock, (northeast of Cedar Key) 75F, winds 12 - 20 with bursts of gusts. drizzling. the air feels like there's a big storm nearby. just filled 11 five gal. buckets, six 2.5 gal. buckets, two 20 gal. tubs, 1 bathtub, and topped off the stock tanks. one never knows...


A-yup.....did the same yesterday afternoon here NE of Chiefland. 15 cattle feed tubs, 3 55 gal drums, 5 5 gal buckets, 4 7gal inside the house with a spigot & topped off 3 stock tanks.......takes awhile to do that stuff !!
Quoting 868. StormJunkie:



Where on James Island?

Per Gov Haley, there are 100 people on Daufuskie island that refuse to Evac.


Here is a webcam from Hilton Head, right next to it. Not looking good already, still have 24 hours to go.
http://www.beachcamsusa.com/hilton-head-island/hi lton-head-island-beach-cam
And I thought I had seen everything hurricane-wise. Here in Boca Raton (2 miles from the ocean) we received very little in the way of winds. And most shocking: We didn't lose power with a cat. 4 only 50 miles away. I regularly lose power during strong thunderstorms and in past hurricanes (Frances, Jeanne and Wilma) we lost power almost immediately!
SCEMD
@SCEMD

Leave NOW if you're in a SC evacuation zone. Call emergency hotline 1-866-246-0133 for info on nearest shelter. READ and HEED. #Matthew
Quoting 932. rpewter55:



Would you also like to tell us your story of walking to school 10 miles in 10 feet of snow--uphill both ways?
Quoting 935. mintyone:

Thank you to the National Hurricane Center for keeping a lot of people safe. (If people don't heed your warnings that is their problem but you tried).
Quoting 932. rpewter55:



Would you also like to tell us your story of walking to school 10 miles in 10 feet of snow--uphill both ways?


We actually went to school in the snow - crazy concept I know..
For those still in coast GA, SC and NC (or trying to convince loved ones not to stay), here is what "weak" Matthew can do for storm surge:

Google Map Location


News Feed (via Twitter)
1042. Michale
Well, as a "devastating" and "catastrophic" Category 4, here in St Augustine, we've seen nor'easters that packed more punch... :^/

Another media-created Armageddon that epic-ly failed to materialize.... :^/
Lots of storm surge and flooding starting to come into Northeast Florida. St Augustine flooding badly into downtown and historic area. Jax Beach storm surge coming into the eastern streets, Mayport reported to have historic flooding and Fernandina flooding badly also. My daughter finding pictures of intense flooding and storm surge in many places, and one of the Jax Beach pier completely covered in water and waves. No wonder the cam there is out. Weather Channel showed surge maps going up the coast talking about all the islands and areas and storm surge predictions, started at St Augustine and went up to South Carolina, but totally skipped talking about Ponte Vedra Beach altogether. Don't know why, since it showed a lot of flooding off the Intracoastal.
Am starting to really wonder what is happening surge wise in Ponte Vedra Beach where I live but there is no news on it.

www.actionnewsjax.com


Quoting 1042. Michale:

Well, as a "devastating" and "catastrophic" Category 4, here in St Augustine, we've seen nor'easters that packed more punch... :^/

Another media-created Armageddon that epic-ly failed to materialize.... :^/



WHAT YOU SEE IN YOUR YARD IS NOT WHAT HAS HAPPENED NEARBY. You must be inland and INSULTING all the people and businesses flooded downtown and on Vilano Beach like my uncle. Can see it on Twitter.
1045. hamla
Quoting 1037. bocawind:

And I thought I had seen everything hurricane-wise. Here in Boca Raton (2 miles from the ocean) we received very little in the way of winds. And most shocking: We didn't lose power with a cat. 4 only 50 miles away. I regularly lose power during strong thunderstorms and in past hurricanes (Frances, Jeanne and Wilma) we lost power almost immediately!
consider your self a lucky human just ask the relatives of the 840 dead folks in haiti


















=
Quoting 1037. bocawind:

And I thought I had seen everything hurricane-wise. Here in Boca Raton (2 miles from the ocean) we received very little in the way of winds. And most shocking: We didn't lose power with a cat. 4 only 50 miles away. I regularly lose power during strong thunderstorms and in past hurricanes (Frances, Jeanne and Wilma) we lost power almost immediately!
1046. Michale
Quoting 1044. BarometerGirl:



WHAT YOU SEE IN YOUR YARD IS NOT WHAT HAS HAPPENED NEARBY. You must be inland and INSULTING all the people and businesses flooded downtown and on Vilano Beach like my uncle. Can see it on Twitter.


It's not only my yard, it's the neighborhood I am in and the surrounding area......

Yes, there is flooding and yes there are trees down..

But it's simply NOT the catastrophic devastation that was fear-mongered....

There are individual instances of destruction, yes..

But we were told that it would look like a lawn mower went over the area on low cut and that simply DID NOT HAPPEN...

Yell at me all you want, but the simple fact is, the media was fear-mongering...

Quoting 1046. Michale:



It's not only my yard, it's the neighborhood I am in and the surrounding area......

Yes, there is flooding and yes there are trees down..

But it's simply NOT the catastrophic devastation that was fear-mongered....

There are individual instances of destruction, yes..

But we were told that it would look like a lawn mower went over the area on low cut and that simply DID NOT HAPPEN...

Yell at me all you want, but the simple fact is, the media was fear-mongering...




The storm never made landfall and never really got to the intensity that they were forecasting. The media always sensationalizes this type of thing. You should know that and just expect it. Listen to the forecasters who are the pro's at what they do and then make a decision on how you want to look at a storm.
1048. Michale
Quoting 1047. SouthMississippi:



The storm never made landfall and never really got to the intensity that they were forecasting. The media always sensationalizes this type of thing. You should know that and just expect it. Listen to the forecasters who are the pro's at what they do and then make a decision on how you want to look at a storm.


Exactly.. I took into account what was being reported, I took into account almost 20 years of hurricanes in St Augustine FL and then made the decision to stay..

As it turned out, it was the right call to make.... I don't begrudge anyone who DID evacuate and I sympathize with those who DID get some damage..

But for me, the biggest catastrophe is that we ran out of beer....