5/1/08 DISC: SD/IA/NE/MO/KS/OK

[Mike Peregrine]

There was no where else to really talk about this, so I'll open a discussion thread concerning the amazing bow echo/derecho event that steam rolled through metropolitan Kansas City overnight.

Reports of heavy damage across the metro today ... many parts of town (particularly from downtown to the north) are completely closed down, as if hit by a line of multiple tornadoes.

I have never seen a convective wind event like this. The trees were bent over like anything you'd see in a hurricane chaser's video ... and the roar is hard to describe. My entire house was shaking like an earthquake. I'm sure all the Kansas City folks are going to have stories after this one.

Photos and more information are on the Star's website already this morning. This event looks to be much more damaging than any of the tornadic activity that occurred yesterday, as many many homes and businesses were badly damaged and even completely destroyed.

*A few photos on the front page here: http://www.kansascity.com/
*33,720 without power as of 6:30 am
*Link to story on KMBC (taken from CNN).

 

[Jim Zandonai]

Wow what a bow indeed..I was able to capture a few captures and animations of this too ..IT would have looked very impressive if it had been in daylight. We had a similar situation here in 2003 July 5th with 80-100mph winds at 430am...left a mess for weeks.
Good luck down there !

 

[AndrewLee]

One of the guys I work with lives in a neighborhood in the northland that was hit by what looks like a tornado embedded within the line segment. His neighborhood is blocked off and he said their were NWS personnel on the ground already assessing damage. Michael already presented a decent synopsis of the damage so I won't cover the same ground, but this was the strangest event I have ever lived through. The winds were so strong that it reminded me of the times I lived in Houston, TX as a child and we lived through several Cat 1 and Cat 2 hurricanes.

I know there is a great deal of damage across the city and I am sure that we will be getting more information as the day goes on about the extent of the damage.

 

[Mike Peregrine]

I wouldn't be surprised if there was some heavy duty rotation going on up there. GRLevel3 was showing rotation embedded along the line as it moved through Gladstone, as you can see above. Even if this was outflow/gustfront related, there may have been some strong gustnado forces at work up there. You can also see a TVS return and a tornado report down in Linn County on the tail-end cells.

 

[J.B. Dixon]

Here's a radar loop from about 1-3 AM this morning from the Pleasant Hill NWS site. If you're familiar with the KC Metro, if you can locate the Liberty area in Clay County (essentially NE KC), there's an interesting feature that streaks perpendicular to the leading edge of the bow, in the vicinity of Hwy 281/152/I-435. There was considerable damage in this area. It will be interesting to see the damage report, and if in fact there was any rotation imbedded in this particular area.

Mike, this actually shows up on your GRLevel3 Screen capture above, right in the vicinity of the Red House the Red Car icos. I'm probably reaching, I know....

[FONT='Calibri','sans-serif']Kansas City Radar Loop from around 1:00 to 3:00 AM[/font]

 

[Jerry Funfsinn]

Here's a radar loop from about 1-3 AM this morning from the Pleasant Hill NWS site. If you're familiar with the KC Metro, if you can locate the Liberty area in Clay County (essentially NE KC), there's an interesting feature that streaks perpendicular to the leading edge of the bow, in the vicinity of Hwy 281/152/I-435. There was considerable damage in this area. It will be interesting to see the damage report, and if in fact there was any rotation imbedded in this particular area.

[FONT='Calibri','sans-serif']Kansas City Radar Loop from around 1:00 to 3:00 AM[/font]

It looks to me that is the location on the north end of a classic bookend vortex. You can see a donut hole in the radar loop and gradually take shape into a comma head.

 

[Benjamin Smith]

I have family that lives in Gladstone.

They report that they lost an 80 yr old Oak tree in their back yard with very minimal damage. He walked one block to the north (They live @ 72nd and Euclid) and the back part of one house was completely leveled. Thankfully nobody was hurt in the immediate vicinity.

Down here in Peculiar we just had some relatively minor straight line winds. It was amazing to be on the SW side of these storms as they "trained" through the KC metro.

There was some pretty good mammatus formations prior to the main cells coming through the area.

Hope to have some pics up when I go help them clean up this weekend.

 

[Mike Peregrine]

KCTV reports hundreds of homes damaged, 12 destroyed in Gladstone.

http://www.kctv5.com/weather/16120668/detail.html

Lots of photos on that link. Channel 9 also has great coverage here: http://www.kmbc.com/index.html

Channel 4: http://www.myfoxkc.com/myfox/

Independence also took a good size blow from this storm with several businesses destroyed and de-roofed homes. We just went to lunch in northtown and saw a large garage door blown from a building. I'll try to get some photos after work of Gladstone. It's pretty much a war zone from what I'm hearing.

UPDATE - the Star is now reporting that the NWS says at least two tornadoes rated EF-2 and EF-3 are responsible for the Gladstone damage.

 

[Van DeWald]

Rock Valley, IA tornado rated EF2...

Link at the NWS Sioux Falls Web Site

 

[Dick McGowan]

Wow, an EF-2 within the bow echo last night west of Lawrence, KS. From the Topeka NWS:

A DAMAGE SWATH IN NORTHWESTERN DOUGLAS COUNTY WAS FOUND TO HAVE BEEN
CAUSED BY A TORNADO. THE TORNADO TOUCHED DOWN AT APPROXIMATELY 104
AM ON FRIDAY MAY 2 2008, 5 MILES WEST NORTHWEST OF CLINTON. THE
TORNADO REMOVED A GARAGE AND APPROXIMATELY TWO THIRDS OF A HOUSE
FROM ITS FOUNDATION UPON TOUCHDOWN. THE TORNADO CARRIED DEBRIS FROM
THIS HOUSE A FEW HUNDRED YARDS AWAY. THE TORNADO DAMAGE AT THIS
LOCATION HAS BEEN ASSIGNED A PRELIMINARY RATING OF EF-2. THE
TORNADO CONTINUED NORTHEAST FOR TWO MINUTES AND THEN CAUSED A METAL
OUTBUILDING TO COLLAPSE BEFORE LIFTING AT APPROXIMATELY 106 AM ON
FRIDAY MAY 2 2008, 4 MILES NORTHWEST OF CLINTON LAKE. THE TORNADO
DAMAGE AT THIS LOCATION HAS BEEN ASSIGNED A PRELIMINARY RATING OF
EF-0. IN SUMMARY...THE TORNADO IN NORTHWEST DOUGLAS COUNTY HAS BEEN
ASSIGNED A PRELIMINARY RATING OF EF-2 DUE TO DAMAGE THAT OCCURRED
WHEN IT TOUCHED DOWN. THE TORNADO LASTED 2 MINUTES...TRAVELED
ALONG A 2 MILE PATH AND WAS...AT ITS LARGEST...UP TO 100 YARDS
WIDE. THE TORNADO TOUCHED DOWN AT APPROXIMATELY 104 AM...AND LIFTED
AT APPROXIMATELY 106 AM.

 

[John Farley]

In the KC radar loop, the bookend vortex is definitely there, but the other feature that is also there is a mesovortex on the leading edge of the bow echo, as indicated on the still. These are pretty common with storms in Missouri and Illinois and nearby areas. Tornadic mesovortices are most often found at or north of the apex of the bow, and where the bow echo interacts with some pre-existing boundary, which can be seen with the small line of storms or showers ahead of the bow echo. Sometimes tornadoes with these mesovortices can be quite strong, as in the Fairview Heights, IL tornado a couple years ago. This looks like a similar event.

 

[Mike Peregrine]

One thing that I've been thinking about ... and this isn't accusatory, since it is just the nature of weather and we all know this ... but I was surprised there were no tornado warnings, if even for damaging straight line winds. Dick's post even indicates that there were warning-worthy events going on as the storm was ramping up over Lawrence. Everyone I have spoken to in Kansas City was awoken violently by the roar of the wind, not by sirens -- maybe they were sounding but we just couldn't hear them for the noise of the storm, I have no idea. One fellow in Gladstone was awoken when his house lifted off its foundation and he fell out of bed and hit the wall.

Everyone was well informed and knew that there would be severe weather that night - and the first round came through and interrupted people's TV viewing, so most people believed the biggest threat was over by the time they went to bed. This really was like getting blasted out of bed by an earthquake, that's the only way I can describe it. I hadn't gotten any sleep the night before (like 2 hours tops), so I was totally OUT COLD. But when that wind hit I was instantly wide awake and it was a scary jolt. I watched all my neighbors lights come on as well. Pretty wild ride ...

This almost makes me think that we put too much confidence in our warning system anymore and we need to start reminding people that anything and everything is possible on a storm day. All bets are off.

Here is the EAX rundown:

As the Bow Echo moved through the Kansas City it encountered one of several smaller thunderstorms moving north ahead of it. As this small thunderstorm was ingested by the Bow Echo it spun up tornado which moved across areas northwest of Liberty, affecting locations in the vicinity of Cookingham Drive (Hwy 291) and 112 Street.

So was the Independence damage strictly straight-line? I saw photos of an Arby's over there that was pretty much obliterated -

 

[Marcus Opitz]

Yea Mike, I have heard of some offices activating sirens when a non-tornado devestating wind event is likely to take place. But its rare. From the radar grab you posted, it looks like it was near maximum intensity when it crossed over the KC metro area. I wonder how that old apartment I used to live in held up?

 

[Damon Scott Hynes]

This almost makes me think that we put too much confidence in our warning system anymore and we need to start reminding people that anything and everything is possible on a storm day. All bets are off.

I have been thinking about this for years--I don't want to have warnings that precise, for a number of reasons.

1. To paraphrase a passage from Grazulis' Sig Tor: Perhaps some time in the future there could be enough sampling sites and computer processing power to tell what house will be hit by a tornado a week ahead, but the technology hasn't been invented yet (and no government could afford it).

2. I use this example a lot and it hasn't gained traction any time I've brought it up, but here goes again. The first time a gustnado or landspout or cold-air funnel flips a school bus or causes a jetliner to stall and crash, that's the last time these types of tornadoes won't be warned for. But the technology isn't there to spot these or their precursors ahead of time, most landspout-caused tornado warnings are issued because someone saw it and called it in!

3. So there are these limitations. But the attitude of the public is that they don't want to be bothered unless the threat is locallized to the city-block level. This is abetted by the practice by both NWSFOs and television to give time-and-place nowcasts. 'This storm will affect rural areas of Bon Homme County.' (Public hears 'rural' and tunes out, and wonders why Desperate Housewives was interrupted.) 'I've put the WhopperDoppler VectorVictor on this storm, it'll be near Blue Springs at 6:30, Grain Valley at 6:35, Odessa at 6:45' (a. different parts of the storm will affect these locations. b. If the storm hits Blue Springs at 6:27 or 6:33, or Blue Springs just gets pea-sized, there goes credibility. And don't get me started on the cry-wolf rotation marker doohickeys.)

I hear a SVR, I treat is like a TOR and so do most of us. We all have seen idiots wandering around in the middle of a TOR-warned county, but there's an order of magnitude more of them during a SVR. But the potential to have your day ruined is just as likely.

 

[Mike Peregrine]

Damon makes a lot of good points.

There's actually an article on the subject in the Star today, which I just found about five minutes ago ... evidently a lot of folks thinking about it. Lots of debate starting up in the discussion thread in there. So much of this really is typical human behavior during dangerous situations. Everyone here needs a weather radio - -