September 19, 2016



Forecasters discuss Hermine impacts on Hatteras
...WITH AUDIO

The week after Tropical Storm Hermine passed over the Outer Banks, two meteorologists from the National Weather Service Office in Newport/Morehead City, N.C., spent the better part of a day on Hatteras Island looking over the impacts from the high winds and the storm surge.

During their day on the island,  they sat down for  an interview with Island Free Press editor Irene Nolan for her Radio Hatteras show, "To the Point," which was broadcast on Sunday, Sept. 18.

Hermine approached the Outer Banks with heavy rainfall on Friday, Sept. 2, and passed over the area on Saturday morning, Sept. 3. The rain bands with Hermine produced three tornadoes -- including one early Saturday morning that destroyed about five camping trailers and cabanas at Hatteras Sands Campground in Hatteras village.

Also, as Hermine passed over the islands and into the Atlantic, the north wind picked up to sustained mid-30s with gusts over 60 and a storm surge rushed into the southern Hatteras Island villages and Ocracoke.

The surge was especially high in the southern villages of Frisco and Hatteras, surprising some residents and many visitors.

Nolan's guests -- Richard Bandy, meteorologist-in-charge at the local NWS office, and David Glenn, science and operations officer -- said that islanders should not have been surprised by the height of the flooding.

"But we are not surprised that some people were surprised," said Bandy.

He added that some people, especially visitors, tended to look at the event as "just a tropical storm." But he noted that a tropical storm can have a wide range of impacts, and the impact from Hermine on Hatteras was on the "stronger end" of what might be expected.

Bandy and his staff at the NWS office, in a series of briefings in the days leading up to Hermine, forecast "significant" water level rises of 1 to 3 feet above ground level on the island.  And, that, he said, is about what happened.

At Nolan's house in Brigand's Bay, Bandy and Glenn measured a water level rise of 2 feet, 4 inches above ground level and 3 feet, 6 inches above normal water level.

In Hatteras village, they said most of the storm surge was 2 to 3 feet with flooding up to 4 feet in lower areas.

Bandy said the "above ground level" designation -- not "above normal" -- is what the Weather Service has been using for about five years.

"We hope that message got around," Bandy said, "and we believe it did from talking to people down here -- but maybe not with tourists."

The change, he said, was an effort to "simplify" forecasting storm surge and make it easier for people --especially visitors -- to understand.

The top end of the 1- to 3-foot surge forecast is what most people on southern Hatteras saw, the meteorologists.

"We can't exactly forecast the exact spot that's going to get the highest surge, but everybody should be prepared for that top end," Bandy said.

"Obviously, there are higher and lower spots in every yard," Glenn added.  "That's one of the difficulties of forecasting."

If the wind had been more northwest than north, which is what it was, then northern Hatteras Island might have had the higher surge.  Or if the wind had been higher or lower that would have affected the flooding levels.

As a matter of fact, the meteorologists noted, none of the forecast models showed any significant storm surge on Hatteras or Ocracoke, but the NWS kept it in the forecast since "there were a lot of things going on with this system."

Namely, they said, Hermine was transitioning from a tropical to a post-tropical system. The cyclone's concentric wind field was elongating and stretching out.

Bandy added that the Hurricane Center's new storm surge maps "didn't do a really good job" in Hermine because it was a transitioning storm.

"The maps showed most of the peak surge north of our area," he said.

They also said that "we dodged the bullet on the oceanside." 

Though Buxton had some overwash at high tide in the days after the storm, Hermine did not slow down and intensify when it moved off the coast, which could have caused many more cycles of pounding waves at high tide and much more damage.

Even if a few folks want to quibble about the storm surge forecast, no one will take issue with the tornado warning that ended up saving folks from serious injuries -- and perhaps saving lives -- in Hatteras village.
David Glenn was on duty at the Weather Service office in the early morning hours of Saturday, Sept. 2, as meteorologists were carefully watching Hermine's rain bands come on shore.

Glenn said he doesn't think most people focus on the threat of tornadoes in tropical cyclones, but the threat is very real and they can "appear very quickly and then be gone."

The one that hit Hatteras village, he said, actually formed offshore and was noted by a meteorologist watching the radar. He added that having a 15-minute lead time for this type of tornado is almost unheard of.

The Weather Service issued a tornado warning for the area of the Hatteras ferry landing at about 12:45.  It is estimated that the tornado touched down at Hatteras Sands Campground around 1:02 a.m.

Three people received minor injuries, but there was no serious injury and no loss of life because some of the campers heard the tornado alert on their cell phones and took cover in the bathhouse.

Bandy said the Weather Service was really pleased that the new technology worked and that people got the tornado warning on their cell phones.  The technology is designed to work whether the cell phone owner has downloaded an app or not.

The preliminary classification of the tornado was an EF0 with winds of 80 mph.  It cut a path 100 yards long and about 25 yards wide in the campground.

In the coming days and weeks, the local meteorologists will be analyzing their forecasts and Hermine's impacts.

"I think there's a lesson to be learned from every storm," Bandy says.

Perhaps, he said, the Weather Service should "tweak" its briefing packages to separate out the Outer Banks, and to consider visitors more in the impact statements.

Bandy noted that the Weather Service would be working closely with Dare County Emergency Manager Drew Pearson, who guided the meteorologists around Hatteras and put them in touch with some of the island's first responders.  Bandy and Glenn also met with county officials in Manteo before heading to Hatteras.

To listen to the interview, which is about 30 minutes long, scroll down to the "To the Point" logo and click on the arrow.

"To the Point" is broadcast on the island's community radio station,101.5 FM on southern Hatteras and 99.9 FM on northern Hatteras, at 5 p.m. on the first and third Sunday of each month.  It is repeated on the second and fourth Sunday. Those who don't live on Hatteras can listen to the show on Sundays through live streaming at www.radiohatteras.org.


MORE ABOUT RADIO HATTERAS

Radio Hatteras is Hatteras Island's community, non-profit radio station and depends on grants, memberships, and underwriting.

It broadcasts around the clock with news -- including such things as surfing and fishing reports -- community announcements, music, and special programs. The station is also  streamed live. To listen, go to
www.radiohatteras.org.

Our community radio station also needs your support, and you can give that by purchasing a membership or by underwriting the station if you are a business or another community non-profit.

Radio Hatteras memberships are $50 for a family, $25 for an individual and $10 for a student. Mail memberships and other contributions to Radio Hatteras, P.O. Box 339, Frisco, NC 27936.

E-mail [email protected] or call (252) 995-6000 for information about underwriting opportunities.


            
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