Sandy Semantics and Communication Confusion

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Prior to hurricane Sandy’s arrival in the northeast the National Hurricane Center decided against issuing hurricane warnings north of the mid Atlantic. Their reasoning was that the storm would be transitioning from a tropical system to a post-tropical storm.

Based on existing policy, once the storm became post-tropical, the NHC would have to drop all hurricane warnings and local NWS offices would need to issue a new set of warnings, statements, and advisories.

This is how the NHC described their decision (which was, apparently, not solely theirs but one coordinated with other NWS/NOAA entities) in their forecast discussions during the day on Saturday.

5 a.m. Saturday NHC Advisory
5 a.m. Saturday NHC Advisory
11 a.m. NHC Advisory
11 a.m. Saturday NHC Advisory
11 p.m. NHC Advisory
11 p.m. Saturday NHC Advisory

I haven’t commented on this decision on the air or on this platform up until today for several reasons. While some media outlets and blogs harped endlessly on the NHC decision to not issue warnings/watches immediately prior to landfall I thought it was best to ignore their decision not to issue, focus solely on the expected impacts, and call the thing a hurricane both on air and on the blog. After the fact, enough had been written about where I didn’t have a whole lot to add!

Far too much time was wasted by some explaining what the storm’s structure would be and what to call the storm during the time people were (or should have been) preparing or evacuating. Frankenstorm (which came from the NWS), superstorm, hurricane, or hurricane inside a nor’easter, etc. When communicating a major, historic, and dangerous weather event wasting any time on semantics is dangerous business. No need to make the message any more confusing than it needs to be!

Following the storm there was near constant chatter in weather circles (including from some in the National Weather Service) about the NHC decision. Very little of it was supportive.

I disagreed with the NHC decision. Strongly. Most tropical storms that impact New England are transitioning to extra-tropical or post-tropical by the time they reach our latitude. A combination of colder water and interaction with the mid latitude jet stream kick starts the extra-tropical transition (ET) process. Most storms (e.g. Irene, Floyd, Bertha, Gloria, etc.) weaken as they undergo ET. Sandy strengthened as it underwent ET.

Extra-tropical transition is not a binary process. It’s a continuum. There’s not switch that gets flipped that tells you “Yup, that’s it, this storm became extra-tropical at 7:33 p.m..” How the NHC knew the storm would be post-tropical with a great deal of certainty Saturday morning (48+ hours prior to landfall) is a mystery to me. While great strides have been made in ET research over the last decade (see research by Hart and Evans), it’s still a challenge to predict.

What made the National Hurricane Center’s decision so confounding to me is that for previous storms that were undergoing ET the NHC maintained them as “tropical” and kept tropical warnings up until the threat diminished for coastal areas. Those were for weakening storms undergoing ET! Why would they do it for a strengthening storm undergoing ET!?

One of the reasons, as mentioned in the NHC discussions on Saturday, was the possibility of the need to change from tropical to non-tropical warnings which, due to the inflexibility of the warning system, would have been time consuming for the already tightly staffed NWS offices and probably confusing to the end-user. The answer that makes the most sense to me would have been continuing to call the storm a “hurricane” until it had moved inland. There’s certainly an argument you could make that the storm was still a “hybrid” system that had both tropical and non-tropical characteristics like so many other hurricanes that impact this region.

Earlier today, Accuweather reported that the National Hurricane Center has already changed its policy for future storms.

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 National Weather Service, according to the Washington Post, now denies this change has been made and says it’s a proposal that has not been adopted.

Regardless of what actually has occurred the interview with Accuweather by NHC Science and Operations Officer Chris Landsea was surprisingly frank and open.

“Sandy was not ideal, and the way we handled it was not right. But we’re fixing it,” Landsea told AccuWeather.com.

“We realize this was not satisfactory and we want to make it better for next year.”

The post-Sandy discussion, thus far, has been a bit bizarre. The National Weather Service ordered a service assessment to be co-chaired by Mike Smith of Accuweather then suddenly cancelled it (covered extensively here, here and here). Meanwhile, the New York Times reported that some in New York City Mayor Michael Bloomberg’s administration were throwing the National Weather Service under the bus for contradictory forecasts after the shocking decision to leave nursing home residents in their facilities located in flood zones.

Today, according to the Philadelphia Inquirer, NJTransit threw the National Weather Service under the bus as well. Not surprisingly, that’s not sitting well with people at the local National Weather Service offices who did a phenomenal job when, in some cases, they had one hand tied behind their back by the NHC. Here’s how a meteorologist at the Mount Holly NWS office responded to the comments by NJ Transit on Twitter.

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I found the National Weather Service forecasts from our local offices (Albany, Taunton, and Upton) to be nothing short of perfect. We worked with them closely through the event and they couldn’t have been better. I’ve heard extremely positive things about the job the embedded National Weather Service incident meteorologist did with the Connecticut Office of Emergency Management prior to and during Sandy. While issuing a seemingly endless number of products, statements, and warnings they were responding to our questions within moments and we worked together to share thoughts and information on storm surge, wind forecasts, and other Sandy related issues. I couldn’t have asked for anything more, particularly from the Upton, NY office.

While the NHC’s decision to not issue warnings muddied the message in some cases, the message from the local National Weather Service offices could not have been any more clear. There were bigger issues than the lack of hurricane warnings, in my opinion. The lack of education and complacency in parts of New York and New Jersey was and is quite concerning. How much did Irene’s relatively minor impact around New York play into that complacency is unclear. How much Mayor Bloomberg’s initial downplaying of the storm on Saturday played into it is also unclear. How about New York City and New Jersey’s hurricane “drought” over the last few decades? Did people think they were “immune” from Sandy’s wrath no matter what the forecasts were?

It appears the NHC is taking steps to rectify their rigid rules and policies to become more common sense and practical. That’s good. Flexibility and removing barriers to effective communication is a good step to improving weather warnings in the future. The much larger issue, however, is figuring out how people best respond to weather warnings. In order to respond to a warning you need to know, and believe, that you’re in a vulnerable place. A warning people don’t listen to isn’t any good.

AccuFail

Accuweather, the Pennsylvania-based private weather forecasting company, is no stranger to criticism from the meteorological community. Their website provides more sensationalism than forecasts and in general is held in very low regard by the profession.

They do some things quite well, however. They’re a money making machine and their forecasts tailored to some specific clients are about as good as they get. The radio forecasts you hear on WBZ in Boston or WCBS or WINS in New York are generally superb. Don’t expect to find a superb forecast on their website or from one of their sensational columnists, however.

In an effort to push the envelope and draw eye balls to their website they’ve begun to issue 25-day deterministic forecasts for locations across the country. Precipitation forecasts to within a hundreth of an inch and exact temperature forecasts as well!

Here’s the forecast for April 28th in Hartford.

Only 0.05″ of rain. Not bad! And not too breezy either – only WNW at 6 mph.

What a joke.

There’s a way to provide forecasts beyond day 10 to customers that are of some use. This is not the way.

Being able to express uncertainty in any forecast is very important, particularly when the forecast goes much past a day or two. Expressing uncertainty (both high and low confidence) is something that most meteorologists aren’t very good at. It’s difficult to communicate uncertainty whether it’s about a tornado warning or a 5-day forecast or a snow forecast.

Using a probabilistic over a deterministic forecast is one of the only ways to provide a forecast of any use beyond day 10 and especially beyond day 15.

Unfortunately this 25-day forecast is just a gimmick. It’s a stunt to grab publicity and eventually drive traffic to their website. Things like this make the profession look bad and are of absolutely no use to anyone.