PRINCEVILLE — The images of Princeville, days after Hurricane Matthew dumped more than 15 inches of rain on the town and the Tar River watershed, are still shocking.
National guard trucks drove through town streets, but there was water almost up to the tops of their wheels. The trucks passed cars in parking lots that were submerged up to their rooftops. Neighborhoods were flooded; water was lapping at the doors of houses. Town hall had standing water throughout the first floor.
“We in the weather service along with our partners are already beginning to talk about what we can improve in our forecasting following Matthew,” admits Rick Knabb, director of the National Hurricane Center. “It all centers around the fact that water is so heavy, damaging and deadly, and I think nationally and even worldwide, we are not afraid enough of water.”
It’s not that the forecasting of Hurricane Matthew’s arrival was wrong; the time and location of the storm’s hitting the coast was spot on. But the amount of rain it dumped on the state and the effects of all of that water weren’t clearly understood.
“We think of hurricanes as these big wind machines and the wind can be damaging and deadly, but nine out of 10 people who die in landfalling tropical systems die due to water,” says Knabb. “Historically storm surge is the biggest killer, but right behind it is inland flooding due to all the heavy rainfall. Wind does kill, but it’s the water, and people don’t have enough fear for the water given all of the lives it is taking.”
So the National Weather Service is now giving water, a hurricane’s deadliest threat, its own alert. That’s because storm surge and hurricane force winds often don’t happen at the same time and place.
Starting with the 2017 Hurricane Season, storm surge watches and warnings will now be separate from hurricane alerts. Storm surge watches will be issued when flooding is possible. Storm surge warnings will be issued when flooding is expected.
The new warning system will also emphasize what authorities hope will be different responses from the public, depending on the warning. The call to action for storm surge is evacuation; to get out of the area before the waters rise. The call to action for hurricane force winds is to take shelter.
“We need to worry about the individual hazards and not worry as much about the track, where the eye is or what the category is,” adds Knabb.
Hurricane Matthew was a category one storm when it arrived in North Carolina. The heavy rains associated with the storm triggered inland flooding. So the National Hurricane Center plans to make inland flood threats more visible in maps and warnings. Local flash flood watches and warnings will also be updated in real time.
The National Hurricane Center will also highlight forecasts from its sister agency, the Weather Prediction Center, which focuses on local flood warnings and excessive rainfall outlooks.
“It’s very important for us to understand how the public is perceiving our information, so people can make their plans ready and early, and what we call that is making America a weather-ready nation,” says Craig McLean, assistant administrator at NOAA Oceanic and Atmospheric Research. He adds that the storm surge forecasts and warnings have been in development for several years. The agency has also been testing the public’s response to the warning system, to determine the most effective way to present the information.
“The best forecast can be scientifically brilliant, but if the public doesn’t understand how to use it with a state of readiness and preparedness to respond, and then recovery after an event, we haven’t fully done our jobs,” adds McLean.
The new forecast tools are an immediate response to the lessons learned from Hurricane Matthew. The U.S. Department of Homeland Security’s Coastal Resilience Center of Excellence, based at UNC-Chapel Hill, is studying a longer term response.
“We have a good understanding of the risks we face, in, for example Eastern North Carolina, because we have some of the best floodplain mapping programs in the country,“ says Gavin Smith, director of the Center. “However, taking what we know about risk and conveying it into effective policy and good planning is one of the challenges. It appears there is a disconnect between the findings of risk and the adoption of risk reduction policy, which includes land use and limiting building in harm’s way.”
- Reporter's Blog: National Hurricane Center Debuts New Look for Cone of Uncertainty