Interesting Weather Information

Monday, July 10, 2017

Why I Critisize @NWSILN

Over the years I have not hesitated to be very critical of the National Weather Service Forecast Office in Wilmington, OH.  I will continue to speak out when there is something the public needs to know. After all NWS works, indirectly, for you and you have the right to know how your tax dollars are being spent.

Most recently I discussed what seems to me to be an over-the-top approach to Areal Flood Advisories (AFA). The number issued by @NWSILN is way more, in fact 261% more through July 7, 2017 at 10:10 AM than any other NWSFO in the region. That is the subject of my previous blog post dated July 6, 2017.

A local Cincinnati TV meteorologist suggested that I just ignore the huge number of AFAs because they are not "life threatening". He scolded me for calling attention to @NWSILN and questioning the unusually large number of AFAs.

There is no benefit from his head-in-the sand approach to dealing with real issues that impact public safety. Frankly I was surprised at the naive suggestion by the meteorologist and his reluctance to use his authority to better inform the public.

He is correct that Areal Flood Advisories do not represent immediate life threatening situations. They are meant to call attention to potentially life-threatening situations and are therefore a "heads up".

However, this well meaning meteorologist seems to have forgotten about the "cry wolf effect".

Image Courtesy of: http://www.insurancejournal.com
The public is now barraged with a confusing assemblage  of advisories, watches and warnings leading to information overload.  False Alarm Rates are high  because of the very nature of weather events, the limited availability of real-time data and the fact that all of us involved in informing the public are human and we do not always get it right.

Include in the mix the "social media/app effect" and an individual may get a single warning multiple times.

After a while it all becomes blah-blah-blah.

My point is that modern communications technology may very well multiply the "cry wolf effect".

Two recent studies find that the "cry wolf effect" (links below) is real and false alarms reduce the number of people who take action during threatening weather. Both studies also find that the issue is complex and a small reduction in the FALSE ALARM RATE has little effect.

Reading between the lines: my thought is that large reductions in the FALSE ALARM RATE may reduce inaction by weather information users. But for the reasons above that may not be possible.

What the authors did find is a clarification statement like, "there is a 90% chance of flash flooding ..." decreases the number of people who ignore potentially life-saving weather information.

Before you go apoplectic, I know there are problems with probability statements and some other form of qualifier may work better.

Here's is another thought.

Instead of blasting the public, every time it looks like a funnel may touch down due to rotation seen by radar, with "tornado warning .... take cover immediately"; Why not qualify the warning.  with something like, "Tornado warning ... radar indicates a small funnel may touch down with winds possible to 90 mph... take cover immediately".

Meteorologists know the difference between the leading edge spin-ups and the monster funnels born from a strong mesocyclone. Isn't the public deserving of the whole truth?

Luckily, most tornadoes are F/EF0s and F/EF1s.  That's is important because in the county warning area under the responsibility of @NWSILN, since 1950 there have been no deaths - ZERO -  from F/EF0 and F/EF1 tornadoes. (Some sources report a single death in Grant Co. from an F1 but it is unconfirmed).

Current initial NWS tornado warnings treat a weak EF0 funnel as being equal to devastating, deadly, much stronger, longer-lived mesocyclone tornadoes. (Note this is not an @NWSILN policy but a policy set up for the entire NWS).

Here is an example of a "tornado"  that was 10 yards wide and on the ground for 20 yards (10 yards/20 yards - you read it correctly) on May 1, 2012 west of Lebanon, OH. Here is the link:

https://www.weather.gov/iln/20120501_WLebanon/


We all remember the EF4 tornado that struck Piner, KY and the EF3 that struck Moscow, OH on March 2, 2012.

The initial warnings for these killers treated them no differently than the 10/20 whirlwind linked to above.

I am really just trying to help viewers make an informed decision by calling @NWSILN out when I see something that is not in the public interest.

I hold nothing against any @NWSILN meteorologist. I am sure they arrive at work each day ready and willing to do the best they can.

 If I am willing to openly criticize @NWSILN, however, I have an obligation to point out events when they perform well.

Friday July 7, 2017 @NWSILN issued a tornado warning but there was no tornado. Nevertheless they performed well.  I explain that in my next blog post later this week.

____
____

Here are links to the two academic articles concerning the cry wolf effect. They are full of research jargon.

https://www.stat.berkeley.edu/~aldous/157/Papers/leclerk.pdf

https://www.utdallas.edu/~emk120030/crywolf_post.pdf



Here is where you can read a summary article meant for the general public:

http://www.insurancejournal.com/news/national/2015/01/28/355667.htm




No comments:

Post a Comment