Sunday, May 8, 2011

More On Tuscaloosa, AL Tornado of 4-27-11

**Latest update 5-8-11, 2:15 pm (added/updated track maps)


A devastating tornado caused heavy damage and loss of life in the Tuscaloosa, AL area before making its way to Birmingham on Wednesday, 4-27-11. The above screenshot was taken from the Fox affiliate in Tuscaloosa as the tornado was tearing through the city. It appears that the tornado may have had more than one vortex, which also lines up with preliminary damage reports on the ground. More on this aspect is to come as details emerge...

The severe thunderstorm that produced this tornado originated near Philadelphia, Mississippi earlier in the afternoon.  The storm appears to have produced tornadoes throughout most of the 380 mile path that it took across Alabama and northwest Georgia before ending in southwestern North Carolina late Wednesday evening (see composite radar image below):

National Center for Atmospheric Research

The NWS Storm Survey has declared that the tornado that tracked through the Tuscaloosa and Birmingham areas was "high end EF-4" intensity.  That would equate to winds of approximately 190 mph.

The following are detailed track maps from the official NWS Survey, regarding the Tuscaloosa portion of the tornado track (click to enlarge):

Shows the origin point NW of Union, SW of Tuscaloosa

Closeup of Tuscaloosa Area

Northeast Side of Tuscaloosa, Heading out of Town

The colored triangles along the path refer to specific EF-intensity damage categories:  Blue = EF-0, Green = EF-1, Yellow = EF-2, Gold/Brown = EF=3, Red = EF-4.  In total, this particular tornado was on the ground for 80.3 miles, according to the survey results.  

The radar images below were taken at the exact time the Tuscaloosa area tornado is estimated to have first touched down, at 4:43 PM CDT.  The top image is the radar in reflectivity mode (rain, hail, etc.) while the bottom image is the radar in velocity mode (wind speed & direction):



The small red dot in each of the images shows the latitude and longitude point that the NWS survey team has preliminarily assigned as the starting point of the tornado.

Remember, when looking at the velocity imagery, greens show winds blowing toward the radar site, while reds show winds blowing away from the radar site.  The radar site is located toward the right center of the images.

The next series of radar images shows the storm and tornado as they were moving through Tuscaloosa (just after 5pm CDT).  Note the "debris ball" on the reflectivity image, right under the "Tu" in Tuscaloosa.  The small red dots showing the original initiation point of the tornado are still on these images as well.



For a more detailed analysis of radar data from throughout the Tuscaloosa phase of this devastating storm, please see my related post here.

Here is a still shot of the actual tornado on the ground, taken near the Bryant-Denny stadium:


Here is a video from near the same vantage point:



More extremely impressive videos from Tuscaloosa follow below.  If you find a black box with no play button somewhere along the line, try to "refresh" your browser (some browsers can't handle loading all the pictures and video at once):










The following video is very solid for the first few minutes and good in full screen view.  It starts to get shaky after awhile.  Several views of horizontal vorticies (mini-tornadoes nearly laying on their side and coming out of the main tornadic circulation) and transformer explosions.  Watch toward the right hand side of the tornado and you'll also see debris at several points:



This next video is very shaky.  I don't recommend watching in full screen most of the time or you're liable to get a headache.  These folks are way too close to this tornado, and are very lucky that a large piece of debris didn't clobber them.  Don't try this at home:


Unfortunately (but as you would expect after seeing the above imagery), damage is significant and widespread in Tuscaloosa:











The video below is aerial footage of Tuscaloosa area damage, as shot by an ABC affiliate helicopter.  I have devoted a separate post with screen shots and notations on what I see as significant in this video.  That post is here.


Please keep these folks in your thoughts & prayers, as they have a long, hard recovery ahead of them.  If you don't live in the area and are unable to help directly, please consider making a contribution to a charity that you can trust that you know is helping aid victims in the region.

Be sure to check back frequently over the coming days as I'll be adding more mapping, images and video to this post (and creating posts on other individual storms & tornadoes) as information comes in and storm surveys are complete.

2 comments:

bill said...

Fantastic video. Seems to be more of an outbreak this or maybe I just imagine there is. Thanks.

Rob In Texas said...

You are right, Bill, this was definitely what you'd call an outbreak yesterday. It will go down in the record books for sure. Just where in the books is in question at the moment, but will become clear in the coming days as the storm surveys are completed. Stay tuned!