Wednesday, December 05, 2012

Modifying The Criteria For Hurricane Warnings?

If you missed the news that we tweeted about earlier today, the National Hurricane Center may be providing additional flexibility into the definition of what would constitute a hurricane warning.

From AccuWeather, which broke the news, the new definition is proposed to read as follows:

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.

The old definition of hurricane warnings, from the NHC, reads as follows:

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.
The NHC has stated their proposal is not yet official, however, and subject to the usual bureaucratic review process:

“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.”

The first of probably a few changes have already been made regarding how the NHC forecasters will deal with hurricanes or hybridcanes (Sandy or Perfect Storm-type storms) in the future, if approved, effectively provides flexibility for forecasters at the NHC to include hurricane warnings for storms that are projected to transition from tropical to nontropical (same as posttropical) at some point as they approach the United States.  This is a warranted change and one I completely agree with.

Chris Landsea, who works at the NHC, also stated in the AccuWeather article that the handling of Sandy wasn't the greatest.

"Sandy was not ideal, and the way we handled it was not right. But we're fixing it."

"The main issue is: We want people to get ready for hurricane conditions, and that's why we are changing the definition of hurricane warning to be a little more inclusive of other things than just a hurricane."

Now...let's see something done about doing away with Saffir-Simpson as the standard of record with hurricane classification.  Given Sandy and Irene were both "Category 1" hurricanes that did vastly different amounts of damage, we can't rely on Saffir as the be-all, end-all of hurricanes and forecasters, meteorologists, and the media really need to be less reliant on simplistic scales going forward when talking about hurricane intensity and impact.