4/10/09 Disc: TN/AL/GA

[mikegeukes]

Moderators you can move this to a post discussion, if you want.

Murfreesboro (Rutherford County) Tennessee Tornado.
Some links to pictures and videos of the tornado.

WKRN Nashville
http://www.wkrn.com/Global/story.asp?S=10164304&nav=menu5_2
http://www.wkrn.com/Global/story.asp?S=10165240&nav=menu5_2

WTVF Nashville
http://www.newschannel5.com/Global/story.asp?S=10164123&nav=menu374_2

http://www.newschannel5.com/global/video/flash/popupplayer.asp?ClipID1=3640907&h1=Time%20Lapse%20Video%20On%20Tornado%20Moving%20 Through%20Murfreesboro&vt1=v&at1=Weather&d1=114200&LaunchPageAdTag=News&activePane=info&rnd=21007802

WSMV Nashville
http://www.wsmv.com/index.html
http://www.wsmv.com/video/19149869/index.html

Newspaper:
http://www.tennessean.com/


04-09-09 Mena, AR Tornado was rated a EF-3
http://kamala.cod.edu/offs/KLZK/0904102055.nous44.html

Mike

[Wes Carter]

Here are a few shots I took of the damage in Murfreesboro today. It was horrible, as it always is when it hits a populated area.

[Jeff Russell]

See my report http://www.stormtrack.org/forum/showpost.php?p=221896&postcount=5

Can this cell that passed through the Powell/Rainsville area have had two wall clouds? I was 1 mile north of Rainsville on hwy 75. I observed the cell approach from the SW. Powell is 4 miles WNW of me. Did this storm recycle with a new lowering in that short of distance or did the cell make a jog SE very quickly?

map scale: 1 inch = 1 mile

Jeff

[mikegeukes]

Preliminary Results: Murfreesboro was rated a EF-3
http://kamala.cod.edu/offs/KOHX/0904111640.nous44.html

[mikegeukes]

NWS Nashville has a map of the Murfreesboro Tornado
http://maps.google.com/maps/ms?hl=en&ie=UTF8&msa=0&msid=110609751342067139763.00046746bc93ded9717cb&ll=35.835628,-86.386185&spn=0.30672,0.439453&z=11

[John Wetter]

It's nice to see that kind of detail on the map. Nice!

[Jeff Russell]

Is there a way to go back and retrieve the SPC's day 1 overviews for yesterday? I've looked with no luck. Help please.

Thanks

[Chris Hayes]

Is there a way to go back and retrieve the SPC's day 1 overviews for yesterday? I've looked with no luck. Help please.

Thanks

Sometime in the next few days May 9 and 10 should be on this website here. http://w1.spc.woc.noaa.gov/exper/archive/events/searchindex.html

[Jeff Russell]

Is there a way to go back and retrieve the SPC's day 1 overviews for yesterday? I've looked with no luck. Help please.

Thanks

Sometime in the next few days May 9 and 10 should be on this website here. http://w1.spc.woc.noaa.gov/exper/archive/events/searchindex.html

Thanks Chris, I missed this page.

[Dave Gallaher]

See my report http://www.stormtrack.org/forum/showpost.php?p=221896&postcount=5

Can this cell that passed through the Powell/Rainsville area have had two wall clouds? I was 1 mile north of Rainsville on hwy 75. I observed the cell approach from the SW. Powell is 4 miles WNW of me. Did this storm recycle with a new lowering in that short of distance or did the cell make a jog SE very quickly?

map scale: 1 inch = 1 mile

Jeff

Jeff, as a non-scientist who has chased a large number of storms in north Alabama, I would say yes--two wall clouds or tornadoes in close proximity are not rare around here. My avatar photo is the closest of two tornadoes that I saw within five minutes at that location. One was off to the north, but not so far away that I missed seeing it in AL terrain. A short time after this photo, I had to abandon this position due to a disturbance that was due west of me, closer than this photo and approaching quickly. It did not drop a tube, but I couldn't wait under it to see. (This happened on a high-risk day).

Several years ago, I watched with a local police officer a single cell, very small, that was approaching our position quickly. There were no warnings or watches out. The storm base was barely wide enough to hold two wall clouds, both rotating, and it passed directly over us with an instant slamming wind. So there was possibly an F0 of some kind that day with no apparent condensation funnel, yet it came out of a very small cloud with twin wall clouds.

I've mentioned in posts years ago that the enviroment here seems to favor some miniature severe events. I don't know if these things happen elsewhere, and fortunately they rarely make news since damage is not significant, but they are amazing to observe.

[Danny Neal]

http://northernilstormchaser.com/4-10-09---Deep-South-Outbreak.php - I have compiled 40-45 radar images of the events from 1230 PM to 2 PM and 6PM to about 10PM Central. Feel free to use any of them if you want. It's not really a big deal.

[mikegeukes]

More information about the Murfreesboro Tornado
This damage may exceed EF-3 Intensity once the survey is complete.
http://kamala.cod.edu/offs/KOHX/0904112323.nous44.html

Mike

[mikegeukes]

Updated Information from the NWS Nashville Site 152 pictures on the site
http://www.srh.noaa.gov/ohx/surveys/ss041009_good_friday.php

Mike

[Angie Norris]

Is there a way to go back and retrieve the SPC's day 1 overviews for yesterday? I've looked with no luck. Help please.

Thanks

Jeff, try this way
www.spc.noaa.gov/products/outlook/ (http://www.spc.noaa.gov/products/outlook/)
scroll down to the bottom of the page to retreive the outlooks.

[shane turner]

Those are interesting damage photos. Some of those homes that were swept clean off their foundations appear to be only nailed to the foundation with straight nails. On the other hand there are some homes swept clean off their foundations were I see anchor bolts protruding from the foundation and nearby trees debarked could possibly be at least an EF4. One home appears to be a bare concrete slab but the debris appears to be only about 10-20 feet away from the foundation so I dont think that would be EF5. With an EF5 doesnt a well-built home have to be cleaned off its foundation but also the disintegrated remains have to be blown downwind leaving little or no trace.

[Kiel Ortega]

Those are interesting damage photos. Some of those homes that were swept clean off their foundations appear to be only nailed to the foundation with straight nails. On the other hand there are some homes swept clean off their foundations were I see anchor bolts protruding from the foundation and nearby trees debarked could possibly be at least an EF4. One home appears to be a bare concrete slab but the debris appears to be only about 10-20 feet away from the foundation so I dont think that would be EF5. With an EF5 doesnt a well-built home have to be cleaned off its foundation but also the disintegrated remains have to be blown downwind leaving little or no trace.
While anchor bolts will work to keep the bottom plate on the foundation, it looked on some of the photos that the walls were straight nailed. Also, it looks like some of these homes had crawl spaces as there wasn't really a foundation so much as cinder blocks where the walls attached. Which is interesting because I don't know if the EF scale has any applications for this type of construction (unless it counts as modular home type construction).

[Wes Carter]

While anchor bolts will work to keep the bottom plate on the foundation, it looked on some of the photos that the walls were straight nailed. Also, it looks like some of these homes had crawl spaces as there wasn't really a foundation so much as cinder blocks where the walls attached. Which is interesting because I don't know if the EF scale has any applications for this type of construction (unless it counts as modular home type construction).

That's kind of normal construction practice when you get into areas that are hilly. The ground is rarely level so you have to excavate some to pour your footer then build up to grade with cinder blocks. That's the reason there are fewer slab houses here, most either have basements or crawl spaces. It's not modular construction but I doubt that it can stand up to sideways wind loads as well as a slab house can since cinder block walls are good only for compression loading and not torque loading.

I think one of the things that has to be considered (and probably is) is that Tennessee building codes are not as stringent as they are in many states. For that reason we see the disparity in anchoring the walls to the foundations in these homes. Murfreesboro is also a town that has been somewhat of a boomtown in the past 10 years. There were a lot of builders here and many different levels of quality are represented.

[Dennis Dennison]

Picture 78 shows where a stud was toe-nailed -one nail on each side, and too close to each other, this looks to be a baseboard setup and if so, this is CHEESY construction. An inspector should have caught this

[Mike Krzywonski]

Heartbreaking story of TN tornado: http://www.foxnews.com/story/0,2933,514709,00.html

[Jeff Russell]

I need help interpretering this radar grab from the HUN NWS. http://www.srh.noaa.gov/hun/stormsurveys/2009-04-10/marshallpm.php

I was 1 mile NE of Rainsville which is at the crossroads out of Powell and Sylvania (not marked on their map/ scale of map:4 miles between Powell and Rainsville, 4.5 miles between Rainsville and Sylvania). It looks to me that the tornado passed north of me, correct? Though I did see a rotating wall cloud and possible funnel cloud pass 1/4 mile to my south, moving ENE. I'm starting to doubt the funnel cloud.

Really trying to understand what I saw and what actually happened. Your help would greatly be appreciated.

Thanks,

Jeff

[shane turner]

Murfreesboro, Tennessee tornado was upgraded to a low-end EF4 with winds around 170mph.

[mikegeukes]

APRIL 10TH TORNADO IN MURFREESBORO REACHED EF-4 INTENSITY
http://kamala.cod.edu/offs/KOHX/0904131653.nous44.html

Mike

[mcrowther]

Neat pic from AL over Lake Guntersville

http://wildwildweather.com/forecastblog/wp-content/uploads/2009/04/tornado-771x1024.jpg

[Angie Norris]

Neat pic from AL over Lake Guntersville

http://wildwildweather.com/forecastblog/wp-content/uploads/2009/04/tornado-771x1024.jpg

Ok, that has to be the best waterspout ever!! Any details on the storm and did it hit land?

[Danny Neal]

Ok, that has to be the best waterspout ever!! Any details on the storm and did it hit land? This is a great picture and has to be one of those waterspouts vs tornado over water debates. I remember a long hashed out thread with several decent arguments for or against it. Obviously this was a supercellular tornado, that just so happened to be moving over a lake. It *probably* started over land as a tornado. As the fundamental processes are very different in tornado formation and waterspout formation. I know the politically correct term is a waterspout, but when I think of waterspouts I don't think of a tube like that ;)!

[mcrowther]

This is a great picture and has to be one of those waterspouts vs tornado over water debates. I remember a long hashed out thread with several decent arguments for or against it. Obviously this was a supercellular tornado, that just so happened to be moving over a lake. It *probably* started over land as a tornado. As the fundamental processes are very different in tornado formation and waterspout formation. I know the politically correct term is a waterspout, but when I think of waterspouts I don't think of a tube like that ;)!

This was an EF-3 over land- most certainly a supercellular tornado

[Danny Neal]

This was an EF-3 over land- most certainly a supercellular tornado Indeed sir! I was just in the process of looking up the info/stats on it. Thank you!

[Angie Norris]

This was an EF-3 over land- most certainly a supercellular tornado
Thanks, Matt! I was using waterspout in the classic definition, but there is absoutely no doubt of the supercell origin. I think magnificent would describe it.
Here is the survey report on the storm
http://www.srh.noaa.gov/hun/stormsurveys/2009-04-10/marshallpm.php

[Dave Gallaher]

There's another photo of the same storm on the Huntsville NWS site:

http://www.srh.noaa.gov/hun/stormsurveys/2009-04-10/index.php

This is pretty rich structure for around here. The one good thing about chasing in mountainous terrain is the (however scarce) opportunity for a view like the 'waterspout' image. I'd imagine that came from a resident rather than a chaser--anyone know for sure?

[Brett Adair]

It was a resident female that was visiting the area from what I understand. I saw it in Dan Satterfield's blog....he was giving credit to her. I believe that I saw a potential second tornado in that photo as well. Radar would kind of back up that assumption. Maybe it's just my eyes....

[Dave Gallaher]

It was a resident female that was visiting the area from what I understand. I saw it in Dan Satterfield's blog....he was giving credit to her. I believe that I saw a potential second tornado in that photo as well. Radar would kind of back up that assumption. Maybe it's just my eyes....

I kept looking at that other structure as well, and wondering if it was a scud bomb. It sure looks like another tube...

Seeing a storm this good to the southeast of Huntsville just an hour after I was in the big hail to the west is really frustrating--I'm having to give myself a bust rating now. But there were so many choices that day.

[Dave Gallaher]

I might add that if that is two funnels, it certainly relates to Jeff Russell's earlier posts in this thread regarding two tornadoes this close to each other. Again, I don't think that has been an uncommon occurence in this region.

[Tony Cook]

I kept looking at that other structure as well, and wondering if it was a scud bomb. It sure looks like another tube...

Seeing a storm this good to the southeast of Huntsville just an hour after I was in the big hail to the west is really frustrating--I'm having to give myself a bust rating now. But there were so many choices that day.

Yeah, that second column sure looks like a tube. When I first saw the original photo, I was thinking the whole shot was maybe a fake. When Brett posted the other shot of the main tornado from the NWS HUN page, it was immediately apparent that it was no fake. Best photo I have seen of an Alabama tornado. I'm moving back if this keeps up!

Would be interesting to get to the bottom of the secondary feature. It does look similar to a couple of classic scud bombs I have seen, but would not be surprised at all if it were another tube.

In any case, what a shot...

TonyC

[Dave Gallaher]

Yeah, that second column sure looks like a tube. When I first saw the original photo, I was thinking the whole shot was maybe a fake. When Brett posted the other shot of the main tornado from the NWS HUN page, it was immediately apparent that it was no fake. Best photo I have seen of an Alabama tornado. I'm moving back if this keeps up!

Would be interesting to get to the bottom of the secondary feature. It does look similar to a couple of classic scud bombs I have seen, but would not be surprised at all if it were another tube.

In any case, what a shot...

TonyC

They are still cleaning up Guntersville...

This is the most interesting season we've had up here in a while, Tony. The structure scene has been overall better in several storm days, not near as much soup & splash. And baseball hail? Did you see any of the local photos?

Did you see Jeff Russell's Sand Mountain intercept report, where he was trying to reconcile storm damage in two close and closely timed locales? My experience has been that multiple walls/tors is not unusual here, as in the case of my avatar on the high risk, when I could see two at once, and an almost-wall right on top of me. All this in AL terrain...

I don't want to over-extend this idea, but I keep thinking that with the mini-supes and other things that occur here, like the horizontal rotation on the tail of a small storm cloud I've seen twice now, that there may be some phenomena here that are not normal in the Alley, where bigger storms result from wider dynamics and less terrain influence. As a non-scientist, I get nervous even posting this, but all you real guys have always been patient with me.

[Dave Gallaher]

Link to some more photos (none as good as the 'spout' image):

http://picasaweb.google.com/StormForce31/SevereStorms#5323240830095787666

[Tony Cook]

They are still cleaning up Guntersville...

This is the most interesting season we've had up here in a while, Tony. The structure scene has been overall better in several storm days, not near as much soup & splash...

...I don't want to over-extend this idea, but I keep thinking that with the mini-supes and other things that occur here ... may be some phenomena here that are not normal in the Alley, where bigger storms result from wider dynamics and less terrain influence.

Definitely some amazing imagery coming out of Dixie so far this season. Saw some of Jeff's report. Could not see the Facebook photos since I am apparently the last person on the planet who has not joined, but from the report, it certainly sounds like it could have been damage from separate spinups. Also it is not too uncommon to get separate paths of tornado damage and RFD damage not too far apart. Remember Feb 16, 2001, the small tornado that went down Capshaw Road west of Huntsville:
http://www.srh.noaa.gov/hun/tornadodatabase/tornado.php?type=county&name=MadisonAL

You have to scroll down to find it. Dr. Kevin Knupp at UAH and a couple of his students surveyed the damage and did some research on that case. There was tornadic damage on Capshaw Road and straight line damage (~2 miles south) on Highway 72 occuring at or near the same time. Interesting proximal damage paths occur in such situations, but you can usually sort out what is tornadic and what is straight-line. I have some pretty whacky theories of my own when it comes to some of the borderline straight-line vs. torando damage cases that crop up from time-to-time.

I think all the fringe cases and oddities that pop up just highlight how much there still is to learn. The Guntersville lake photo that appears to show the second tube seems to support the idea that the environment in the area was capable of doing it on Apr. 10th. All very cool stuff!

[Jeff Russell]

Some more pics from Rainsville, AL. BTW, the lowering had rapid rotation.