More On NWS Warnings During Wind Event

Here is some more information to back up what Ken was pounding his fist about in the video I showed yesterday. First, here are weather map animations of the wind event in the Northeast on February 11th, for severe advisories, radar and lightning:

UNUSUALLY LARGE WARNINGS:

Ken pointed out in the video that some of the warnings themselves were unusually large. If you run the IEM COW verification system for the event here in State College, you can see that one Severe Thunderstorm Warning issued by State College covered over 25,000 square kilometers, or 36,000 if you do it by the old county method.

NEGATIVE WARNING VERIFICATION BASED ON WIND MEASUREMENTS:

The COW says that technically the warning "verified" because there were two reports of wind damage within it, but as Ken points out in the video, wind damage does not a Severe Thunderstorm make. The requirement is winds at 58 mph or higher, which were observed to the west of the warning at Johnstown, but not inside it. So one could argue that gust was the reason to create the warning, but the warning itself did not verify.

You can also look at the Pittsburgh warnings versus storm reports (click on a warning title to get the Google Map option).

LACK OF LIGHTNING WITH TORNADO AND SEVERE T-STORM WARNINGS:

I'm not going to rehash this too much here, because I already talked about how it's silly to issue Thunderstorm warnings without lightning, and pointed out how the lightning didn't match the warnings in this blog and this earlier one regarding the Midwest. You can compare the lightning to the severe advisories in the animations above. NOTE: Each image shows the last 2 hours of lightning, so it's kind of an unfair comparison (just looking at the white dots, which are in the last 20 minutes, would be more fair). There were no lightning strikes north of central West Virginia after 8 PM, while the Severe Thunderstorm Warnings continued to roll northeastward.

According to archives from the StormMatrix, there were 334 Severe Thunderstorm warnings between 2/11/09 00Z and 2/12/09 12Z. Ken noted in the video that there were not many more than 1,000 lightning strikes during the warnings in the Northeast (which is 10-50 times fewer than during normal summer thunderstorms). I don't have any way of verifying how many of those 334 warnings were during the 1,000 strikes but that certainly speaks to an extremely small number of lightning strikes per warning.

Report a Typo