just incredible...cant imagine what it will look like once the sun rises tomorrow and they begin to really get a grasp at the extent of the damage.
-
Mark Blue, 1961-2023. See also RIP thread.
Rest in peace, Mark.
Just saw this on the bottom of the SPC LSR list:
0210DADEVILLE TALLAPOOSA AL32838577DADEVILLE TOOK A DIRECT HIT. MULTIPLE REPORTS OF EXTENSIVE DAMAGE.
CNN (on TV that is--Anderson Cooper )finally covering tornado. Lot of heavy breathing on that one video, but understandable. Univ. student, Christopher England:
http://wap.weather.com/outlook/videos/incredible-tuscaloosa-tornado-20459
Must say the forecast discussion at around 6:30 Tuscaloosa hit it:
--
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
636 PM CDT WED APR 27 2011
...SIGNIFICANT SEVERE WEATHER OUTBREAK ONGOING...
.UPDATE...AVIATION DISCUSSION.
.DISCUSSION...
A VERY DANGEROUS SITUATION IS CURRENTLY UNFOLDING ACROSS CENTRAL
ALABAMA...AND SUPERCELLS HAVE ERUPTED ACROSS THE NORTHERN AND
WESTERN SECTIONS OF THE CWA THIS AFTERNOON. A FEW TORNADOES HAVE
ALREADY TOUCHED DOWN...AND REPORTS OF MAJOR DAMAGE ARE STARTING TO
COME IN. THE 18Z SPECIAL SOUNDING THAT WAS PERFORMED PRESENTS A
DESTRUCTIVE SETUP...WITH 2700J/KG OF CAPE...EXTREMELY STEEP LAPSE
RATES...AND DRY AIR ALOFT. 0-3 KM HELICITY VALUES ARE ALMOST 700.
THE PARAMETERS WILL ONLY WORSEN AS WE GO THROUGHOUT THE REST OF
THE AFTERNOON AND EVENING. THE TIME FRAME FOR THE WORST SEVERE
WEATHER WILL PERSIST THROUGH THE EARLY AFTERNOON HOURS FOR
NORTHWEST SECTIONS OF THE STATE...ROUGHLY FROM 2PM TO
8PM...CENTRAL PORTIONS OF THE STATE...INCLUDING THE BIRMINGHAM
METRO AREA...FROM 4PM TO 10PM...AND THE SOUTHEAST SECTIONS FROM
6PM TO 2AM. I CANNOT STRESS HOW SERIOUS THIS SITUATION IS. DO
WHATEVER YOU CAN TO PROTECT YOUR LIFE AND PROPERTY NOW...YOUR LIFE
MAY DEPEND ON IT! ALL WEATHER WILL CLEAR THE AREA AFTER 6Z
TONIGHT...SO THE CLEANUP PROCESS CAN BEGIN.
http://wap.weather.com/outlook/videos/incredible-tuscaloosa-tornado-20459
Must say the forecast discussion at around 6:30 Tuscaloosa hit it:
--
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BIRMINGHAM AL
636 PM CDT WED APR 27 2011
...SIGNIFICANT SEVERE WEATHER OUTBREAK ONGOING...
.UPDATE...AVIATION DISCUSSION.
.DISCUSSION...
A VERY DANGEROUS SITUATION IS CURRENTLY UNFOLDING ACROSS CENTRAL
ALABAMA...AND SUPERCELLS HAVE ERUPTED ACROSS THE NORTHERN AND
WESTERN SECTIONS OF THE CWA THIS AFTERNOON. A FEW TORNADOES HAVE
ALREADY TOUCHED DOWN...AND REPORTS OF MAJOR DAMAGE ARE STARTING TO
COME IN. THE 18Z SPECIAL SOUNDING THAT WAS PERFORMED PRESENTS A
DESTRUCTIVE SETUP...WITH 2700J/KG OF CAPE...EXTREMELY STEEP LAPSE
RATES...AND DRY AIR ALOFT. 0-3 KM HELICITY VALUES ARE ALMOST 700.
THE PARAMETERS WILL ONLY WORSEN AS WE GO THROUGHOUT THE REST OF
THE AFTERNOON AND EVENING. THE TIME FRAME FOR THE WORST SEVERE
WEATHER WILL PERSIST THROUGH THE EARLY AFTERNOON HOURS FOR
NORTHWEST SECTIONS OF THE STATE...ROUGHLY FROM 2PM TO
8PM...CENTRAL PORTIONS OF THE STATE...INCLUDING THE BIRMINGHAM
METRO AREA...FROM 4PM TO 10PM...AND THE SOUTHEAST SECTIONS FROM
6PM TO 2AM. I CANNOT STRESS HOW SERIOUS THIS SITUATION IS. DO
WHATEVER YOU CAN TO PROTECT YOUR LIFE AND PROPERTY NOW...YOUR LIFE
MAY DEPEND ON IT! ALL WEATHER WILL CLEAR THE AREA AFTER 6Z
TONIGHT...SO THE CLEANUP PROCESS CAN BEGIN.
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Drew.Gardonia
last I checked this system had spun 127 tornadoes (per SPC Storm Reports), by the time it's all said and done, this could break the record held by the 1974 Super Outbreak for tornadoes in a 24 hour period. Tragically, this will be an historic day in terms of weather, but not so historic for the people affected by these storms and those who lost their lives.
That footage reminds me of the Andover footage from '91. I can't believe the number of horizontal vortices sprawling out from the tornado!
No, it has spun 127 tornado reports. You can see just at a quick glance that some are the same tornado being reported many many times. No matter how many LSRs come in, it's still 1 tornado.
Elinor McLennon
Amazing video. The sound was incredible. You could hear that guy panting with fear. He was so close to that monster. Thanks for the link. I was going to ask how close he was to it but as soon as he drove through that parking lot and I saw the damage across the street I had my answer.
Elinor McLennon
At first i was puzzled about what i was looking at. I have never seen so many horizontal vortices. That was mind blowing. Like everyone else I can't imagine what daylight will bring.
If I had a dollar for everytime this had to be said today...
TWC just aired an amazing video of a tornado (I don't know which one) developing from a extemely close vantage point and tearing apart trees and powerlines as it crossed the road. Reminded me of the tight small tornado video from Europe a while back. I can't find a link to it anywhere, can anyone find it?
I find it interesting the media was claiming the frontal boundary to be a dryline and not a cold front, which it obviously was.
ABC33/40 did by far one the most amazing jobs I have ever seen broadcast meterologists do with an outbreak. They kept their cool, knew the area, and understood the importance of the situation, making it as dumbed down as the public needed.
Chip
PDailey
The footage also reminds me of the '66 Topeka tornado. It also brings to mind the witness accounts of the Ruskin Heights tornado.
Real simple, speed shear at different levels. Say, 50kts going south at 100m and 50kts in the same direction 90m that contains enough moisture to condense.What exactly causes horizontal vortices like that? Reminds me of Dr. Octopus.
Chip
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If I had to guess, I would say that it's extreme stretching of horizontal vorticity. Typically, when we think of mesocyclones, we think of the tilting of environmental horizontal vorticity (caused by the vertical shear of the horizontal wind) and subsequent stretching of this newly-converted vertical vorticity (the dw/dZ or dB/dZ term). In this case, I can only think that the low-level / near-surface horizontal vorticity (or vertical wind shear near the surface) is so extremely strong that it ends up getting stretched INWARD towards the tornado as a result of extreme horizontal (radial or tangential) inflow. In other words, imagine taking a roll of dough, grabbing one end of the roll, and pulling it outward. In this case, there may be natural "rolls" (perhaps something like a vortex sheet aligned horizontally, with occasional "roll-ups"), and the horizontal acceleration of the wind associated with the tornado is so intense that the vortex tube, of sorts, gets stretched enough to drop the pressure low enough to produce condensation (the tubes that you can see). Actually, like vertical stretching, we are really talking about the gradient in horizontal wind resulting in horizontal stretching. Of course, vertical motion associated with the tornado can then tilt this already-condensed tube upward, resulting in these spiral-tube formations. Again, just my hypothesis.What exactly causes horizontal vortices like that? Reminds me of Dr. Octopus.
PDailey
Is this the video you are referencing Chip?
http://www.youtube.com/watch?v=0NdQPpiFDlA
I thought for so long that this had to be a faked video! Pretty insane (and tiny)
I wonder...when someone gets footage like this, do they just put the camera away and stop chasing forever? I mean, I feel like there's nothing more to see after seeing this..Absolutely amazing.
I'd also be surprised if the total count ends up near the Super Outbreak count. There were a lot of tornadic supercells today, but they primarily occurred over a relatively small area (by comparison to the Super Outbreak); for the most part, most of the tornado reports are from far eastern MS, the northern 2/3 of AL, and adjacent parts of southern TN and northwestern GA (though we can't ignore the other cluster of reports farther northeast). From a pure "totals" standpoint, many of these tornadoes apparently were long-lived, so you'd have 1 tornado per hour compared to maybe 2 or 3 from one supercell. If I remember correctly, we had close to 63 tornadoes in Oklahoma on 5/3/99, and I'm curious to see how many occurred today in AL.
Folks (myself included, I suppose) were surprised we didn't see much in the way of violent tornadoes during the last multi-day outbreak (April 14-15, IIRC). Judging from the radar presentations (which usually is a bad idea), the video collected, and the trickling-in reports, I think we had our fair share of violent tors today.
Folks (myself included, I suppose) were surprised we didn't see much in the way of violent tornadoes during the last multi-day outbreak (April 14-15, IIRC). Judging from the radar presentations (which usually is a bad idea), the video collected, and the trickling-in reports, I think we had our fair share of violent tors today.
Comparisons to '74 should really stop, they really weren't that similar systems at all.
hats off to ABC 33/40 as well, some of the best tornado Coverage I have seen outside of the Plains states.
hats off to ABC 33/40 as well, some of the best tornado Coverage I have seen outside of the Plains states.
It is also a wonder if they will be able to discern today's from last night's tornadoes/wind damage as many of them crossed similar areas in MS and AL.
That video is the one I was referencing, but there was one similar (although a bit bigger) today and I can't find it anywhere. TWC hasn't aired it again either...
Chip
Agreed. James Spann knows his stuff, and is the definition of class under pressure in my book. He has also had some experience in this department:
Dec 16, 2000:
http://www.youtube.com/watch?v=G3Jyqy7qhsQ
Sep 25, 2005:
http://www.youtube.com/watch?v=LW6LYQ9hYEs&feature=related
Apr 15, 2011:
http://www.youtube.com/watch?v=wL2Vz2clkc0
More Spann info:
http://en.wikipedia.org/wiki/James_Spann
TonyC
Chip, I think you are referring to this tornado from Philadelphia, Mississippi:
http://www.youtube.com/watch?v=XInx2RsPIz8
Agreed it is just one of many incredible videos shot from today's outbreak.