NHC reveals reasons for non-issuance of hurricane warnings related to Sandy
AccuWeather.com reports nearly two months after Sandy wreaked havoc on the East Coast, the National Hurricane Center has revealed the thought process behind the decision not to issue hurricane warnings north of North Carolina, which resulted in much miscommunication and confusion for the government and public alike.
Chris Landsea, the Science and Operations Officer at the National Hurricane Center told AccuWeather.com there were three ruled-out options leading up to the final actions made by Branch Chief of the Hurricane Specialist Unit, James Franklin, Deputy Director of the NHC, Ed Rappaport and Director of the NHC, Rick Knabb.
If the National Hurricane Center had continued to issue advisories after the system had transitioned into a post-tropical phase, it may have resulted in a total system failure, according to the NHC.
“We would have risked completely breaking our dissemination system,” Landsea said. “The system is not set up for us to continue to write advisories once the system becomes post-tropical. So, we could have tried that, but we could have broken our way to get the information out and that would have been a humongous disaster.”
That was not an option that they wanted to pursue, he said.
After ruling out that possibility, the NHC addressed transitioning the responsibility over to local weather forecast offices, but resolved that it would have been too abrupt a switch for emergency managers mid-way through the event.
“The emergency managers did not want any part of that,” Landsea said. “That is the worst case for them because they have to switch from dealing with hurricane warnings to dealing with the local warnings — extremely confusing for them and the public,” he said.
“So we heard very strongly from the eastern region — the WFOs — ‘Don’t do that.'”
The decision was made assuming that the hurricane would transition to an extra-tropical cyclone, but it was unclear when that would occur. The uncertainty weighed in their decision-making process.
“We were anticipating it to do that transition to an extra tropical cyclone. We didn’t know when. We didn’t know if it was going to be two days before landfall, a day before landfall, or right at landfall.”
Had they known the transition would occur right around landfall, this could have been viable option, Landsea explained. But without knowing, there was the chance that this option would have resulted in “chaos and confusion.”
The third option was also a bad option, he said. The NHC could have “faked it” for a day or two and continue to call it a hurricane when it was not, but they feared this could have severely damaged their credibility in the future.
“Yes, that would have worked. We could have gotten the advisories out to the U.S. coast, but our credibility would have gone in the tank for us to continue writing advisories on a hurricane when it was clearly a winter storm,” Landsea said.
With these options ruled out, the NHC went forward with writing advisories but the local WFOs carried the warnings.
“[It was] clearly not good. It caused a lot of confusion. We got a lot of grief about it, admittedly,” Landsea said.
After addressing the issue last week at the annual NOAA Hurricane Conference in Miami, the NHC has decided to modify their advisory system to allow for more flexibility, and has revised their official definition of “Hurricane Warning.”
Beginning next year, the NHC will be able to issue multiple advisories on post-tropical cyclones for landfalling systems or close bypassers.
We’ve made the decision already that if the same exact hurricane, same exact scenario was going to happen, we are going to do things differently,” Landsea said.
By Jillian Macmath for www.AccuWeather.com