By: Joe Lauria
As I’ve talked about in previous blogs, my feeling is that the public…my customers…don’t pay attention to the vast majority of severe thunderstorm warnings (SVRs). This is NOT a criticism of the issuing of the warnings from the National Weather Service (NWS)–they have a mandate to follow–rather, this is more of an issue with the criteria and the end results of what typically happens after storms move through.
This project is an outgrowth of our conversations within the Kansas City Integrated Warning Team (IWT) when I brought up this subject in late 2015.
As we get started, I wanted to tally up just how many warnings have been issued since the new hail criteria (from 3/4 to 1 inch diameter) was introduced. Granted the NWS offices in Missouri and Kansas were using the 1 inch diameter hail criteria (from 3/4 inch diameter) for a couple of years prior, but I tallied up from when Central Region adopted the standard, which was in 2009.
I also wanted to see how many were issued at other offices, in southern and western regions as well. I just picked a sampling of weather active county warning areas (CWA). These adopted the 1″ hail criteria 1 year later than Central Region.
I call your attention to the Norman NWS office.
Notice, in the Norman breakdown above, that about 400 warnings were issued based on the minimum criteria alone out of some 900 total warnings last year. That is almost 3 warnings per day issued and almost 1 per day based on the minimum criteria. Granted, their coverage is all of Central and Western Oklahoma, a lot of territory, but I have a tough time thinking folks are paying attention to many of the 900 warnings in 2016.
I wrote a blog last March with these initial findings. I wanted to know what my viewers/readers thought of SVR issuance at the time. It should be noted that the majority of my blog readers are a bit more weather “savvy” than a typical viewer. I asked these questions at the beginning of the blog.
Obviously I’m interested in the “deeper dive” of the 2nd question. Hence what follows. I went into the last 5 years of SVRs issued by the NWS in Pleasant Hill. I checked all the (Impact Based Warning tag information) for the initial reason why the warning was issued.
In particular, I wanted to see the quantity of 60mph wind warnings and/or 1″ hail triggers. Those are represented by the orange bars above and the red bars are the total warnings issued. The percentage values are the 60mph and/or 1″ triggers. So in 2016, roughly 55 percent of ALL warnings issued were for the minimum criteria needed to issue a warning.
I was then curious about the verification of these minimum warning issuances. In most cases, well under 50 percent verified. Of course, warnings are tough to verify many times, especially if they happen in rural areas, or the middle of the night (if a tree falls in the forest does it make a sound?).
So what would happen IF we changed the minimum criteria? How many of these warnings would drop off if we went to 70mph winds and/or 1.5″ hail minimums? The warnings issued are represented by the orange bars. Also note, as I mentioned at the IWT, the actual number of initial warnings issued based on the minimum criteria that then intensified into a 70mph and/or 1.5″ hail tag was pretty small–mostly under 10 per year.
We’re talking about 20 to 25 percent of these warnings would have been issued! In other words, even being a bit generous, 60 to 70 percent of the warnings would have been reduced. That’s pretty significant!
My thought is that IF we don’t issue so many SVRs, when one is issued, our consumers would pay more attention to what is happening. A topic discussed thoroughly on thewxsocial.com, are people fatigued by the sheer volume of warnings?
After I wrote that March 2016 blog…I asked some additional poll questions and was encouraged by the middle answers especially. This though isn’t a perfect process…there are other issues to this research.
After more than a year of research and data collection, this information was recently presented to the Kansas City Integrated Warning Team. According to a poll question, 91% of media/emergency managers/NOAA personnel that attended (about 110) said that something needs to change with regard to SVRs. Joe Lauria is the weekend meteorologist at FOX 4 in Kansas City and can be reached at firstname.lastname@example.org.