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Wednesday, December 5, 2012

National Hurricane Center changes definition of Hurricane Warning in wake of Sandy

As first reported by AccuWeather, just 5 days after the end of the 2012 Atlantic hurricane season and a little over a month after "Post-Tropical Cyclone" (aka, Hurricane) Sandy washed ashore in New Jersey with nary a Hurricane Warning to be found, the National Hurricane Center has re-defined the warning that should have been issued.

This move, while not totally unexpected and certainly in the best interest of their vast customer base, was perhaps unprecedented in terms of how quickly it was made.  Typically, changes to National Weather Service products, watches, and warnings go through a lengthy trial process with suitable time for customer and user feedback, before the final decision is made to make the change.

In this case, I believe (and apparently so did the Hurricane Center) that the uproar surrounding a lack of warnings from the national center as "Superstorm Sandy" came ashore as likely the second-costliest Atlantic hurricane ever and deadliest since Katrina in 2005, was sufficient enough "customer feedback" to press forward with the change, effective immediately.  Below are the previous and new definitions [emphasis added where changes were made]:

Hurricane Warning - old definition:
An announcement that hurricane conditions (sustained winds of 74 mph or higher) are expected somewhere within the specified area. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds.

Hurricane Warning - new definition:
An announcement that sustained winds of 74 mph or higher are expected somewhere within the specified area in association with a tropical, sub-tropical, or post-tropical cyclone. Because hurricane preparedness activities become difficult once winds reach tropical storm force, the warning is issued 36 hours in advance of the anticipated onset of tropical-storm-force winds. The warning can remain in effect when dangerously high water or a combination of dangerously high water and waves continue, even though winds may be less than hurricane force.
It was a shame that the amazing track and intensity forecast provided by the Hurricane Center forecasters had to be overshadowed by the decision to leave warning the public to local NWS offices due to the straight-jacket they were put in by an inflexible process.  It is possible, if not likely, that lives were lost as as result and apparently the Hurricane Center felt that Hurricane Warnings should have been issued for Sandy in their Monday morning quarterbacking sessions.  However, I for one am glad to see this swift and decisive change that will enable the Hurricane Center to more accurately inform those in the path of the next "post-tropical cyclone."

UPDATED: Wednesday, December 5, 8:40pm

Well, there goes the "swiftness" of the decision to change the definition of a Hurricane Warning.

In an e-mail statement this afternoon, NWS spokesperson Chris Vaccaro indicates:
A proposal was raised during the NOAA Hurricane Conference last week for NWS to have the option to issue hurricane and tropical storm watches and warnings for post-tropical cyclones that threaten life and property.  This is one step in the process required before any proposed change to operational products becomes final. As part of our review of the 2012 hurricane season, including the Sandy service assessment, we will review all policies and changes through the existing and established process.
So, did the original statement provided by NHC Science and Operations Officer get misinterpreted by AccuWeather, or did the NHC representative mis-speak?  Either way, it still looks like the Hurricane Center is on the right track.  At least we can only hope...

Special thanks to Nate Johnson (@nsj on Twitter) who provided the updated information.

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