BREAKING NEWS: "THIRTEENTH NAMED STORM OF THE SEASON FORMS FROM DEPRESSION IN THE FAR EASTERN ATLANTIC" (NHC)
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Many of you have asked for my comments on this NOAA / NWS Press Release, or news articles about it, that have come out over the last month or so, hyping this "new" functionality that will be launched on October 1st. The basic ideas is that some U.S. advisories, such as Tornado Warnings, will be issued by a box on a map, instead of an entire County.

Although this is a good change, a lot of the hype is unwarranted. Here's the REAL story:

1. This is an important, good change that will make NOAA warnings more accurate
2. It won't affect the bulk of their advisories but it will affect some important ones
3. This is old news, they started doing this in 2004, if not earlier
4. This is not a unique idea; private companies have been doing this for a long time
5. You will see little change on October 1st. Actually seeing this in reality will depend on the companies using the data.

These are covered in more detail below.

This is an important, good change.Back in July I blogged about a tornadic storm clip the edge of the county where AccuWeather is located here in Central Pennsylvania, I talked about this very problem - that NOAA advisories were issued by county and cause millions of people to get "false positives" - in other words, they were warned when they didn't need to be. Here's a great example of a Tornado Warning that occurred here in Centre County, PA a couple of months ago:

That image only shows the eastern half of our county. Note the warning polygon in red on the right, the storm is heading southeast out of the county, but when the warning went out over TV (as a County Warning), people in State College, the main city, (and further west) were freaking out with no need. Here's the path of the storm as shown by lightning strikes, as you can see only the eastern tip of the county got the storm - most of the county didn't even get rain or wind from it.

2. It won't affect the bulk of their advisories. As far as I can tell (correct me if I'm wrong), this will NOT affect any Winter or Hurricane Advisories, or any Watch (including Wind, Flood, Severe Thunderstorm and Tornado). This is because these advisories are issued for larger areas anyway. The "short-fuse" warnings which concern the extreme short-term and cover small areas WILL be changed to the new format, for example Flood, Severe Thunderstorm and Tornado Warnings. (For the uninitiated, the severity scale is: 1.) Advisory, 2.) Watch, 3.) Warning where the last is the most severe).

3. This is old news. I'm not sure how long NWS has been issuing short-fuse warnings in this "new" lat/lon format, but it's been at least three years, in fact they've been doing it on their website for at least a year. AccuWeather.com RadarPlus was making use of these new "areal" warnings as early as 2004, as proven by the screen captures below:

The yellow and red polygons are the "new" NWS advisories issued by lat/lon.

4. This is not a unique idea. Even before the NWS started doing this, private companies have been drawing areas of storm influence (either manually or automatically). Again I'll use RadarPlus from 2004 as an example, though AccuWeather has been doing this type of thing even longer:

The purple and blue ovals are forecast areas of Small and Large Hail forecast by ADCRP (again, the yellow and red polygons are the "new" NWS advisories issued by lat/lon).

5. You will see little change on October 1st. Actually seeing these new warnings in action will require massive software changes for services that use them. If they haven't already converted to the new format and many services who use the warnings for official business (such as NOAA WeatherRadio and the Emergency Broadcast System that sounds the sirens in your neighborhood and on your TV screen) won't be ready for a while after October 1st. Some, like WeatherRadio, which are tied to county names or NWS "zones" (which may be parts of, or multiple counties) may never implement the technology.

This is all based on what I've read and heard over the last few months. If I'm wrong on anything here, please send me proof and I'll post corrections here.

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