Severe Weather History: First Radar Indicated Tornado Signature on this Date in 1953...

The above YouTube video shows the first ever radar indicated tornado signature (also known as a "hook echo"). It was captured on this date back in 1953 on a radar being tested by the Illinois State Water Survey in Champaign, IL.  

The parent thunderstorm went on to produce the tornado shown below:

Needless to say, technology has advanced quite a bit since the 1950s and 1960s when meteorologists and forecasters sat in darkened rooms watching for the latest sweep of the radar scope, hoping to make something out on the blurry screens.

In a recent post I described the benefits of the latest round of radar technology, dual polarization, which is currently being launched at National Weather Service radar sites around the country.   You can view that article by going here.

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New Technology Coming "Soon" to a Radar Site Near You...

The National Weather Service radar in New Braunfels, TX (which serves the Austin and San Antonio Metro areas) was just put back online about an hour ago after the "dual polarization upgrade" was complete.  It will be interesting to see how the radar performs during the severe weather event that is expected to take place this afternoon.

With this and many other sites coming online recently, I thought it would be appropriate to put the following post regarding Dual Polarization Radar back up to the top of the blog.  The original post from July 9, 2011 follows below:

The first major upgrade to the National Weather Service's WSR-88D radar network in over 20 years is getting underway across the country. The latest technology being rolled out is called "Dual Polarization".

"What the heck is that???" and perhaps more importantly, "what's in it for me???" - you ask?

In a nutshell, the conventional WSR-88D radar sends out a single pulse of radar energy into a storm, which captures a generally horizontal snapshot of raindrops, hailstones, snow flakes, etc. (as shown on the left half of the illustration below): 

The right half of the same illustration shows what Dual Polarization technology will do.  The radar will not only send out a horizontal pulse of energy (red) but also a vertical pulse (blue), which will give us a far greater depiction of the size, shape and density of raindrops, hailstones, snow flakes and other targets.

Dual Polarization (also known as Dual-Pol for short) radar technology has been installed and tested for a number of years at the NSSL in Norman, OK.  Within the last few months the rollout to operational NWS radar sites has begun.  The first site to be installed was at Vance AFB, OK, followed by Phoenix, AZ and Morehead City, NC.  As this is being written, Dual-Pol is currently being installed at radar sites near Pittsburgh, PA and Wichita, KS.  A complete schedule of the rollout, which will continue into early 2013, is located here.  Each installation takes about 2 weeks to complete, during which time the radar unit will be out of service to allow for both the upgrade and training at the local NWS office.

Now that we know what Dual-Pol is, what will it do for us?  Perhaps the greatest initial impact will come in the form of vastly improved precipitation estimates.  With the current WSR-88D technology, a thunderstorm must be in existence for about 1 hour before the radar is able to estimate how much rain is being produced.  With Dual-Pol technology, we'll receive a nearly instantaneous read on rainfall rates.  This will obviously have enormous potential not only in regard to flash flooding & other severe rainfall situations, but also in dealing with snowfall, ice accumulations, etc.

Dual-Pol rainfall estimate (left) vs. WSR-88D estimate (right)

Current technology on the WSR-88D sometimes makes it difficult for the radar to differentiate between hailstones and raindrops, particularly at greater distances from the radar site.  As a result, the 88D often over estimates the rainfall rate with severe storms (mis-identifying hail as heavy rain).  The Dual-Pol technology will make the estimates more accurate in these situations (see the above image for just one example).

Dual-Pol technology will also aid in the tornado warning process.  Right now, it takes a fairly large debris field (which usually means a fairly large tornado) to produce a debris signature on the WSR-88D.  A Tornadic Debris Signature (or TDS) can be detected by Dual-Pol radar in association with a much smaller debris field (which means a smaller tornado).  Please note that I am talking about debris being detected by the radar here, not rotation.  In the database that was used to develop some of the algorithms for the new Dual-Pol radar system, debris signatures were observed with tornadoes as weak as EF2 intensity (winds of 111-135 mph).  Today we would normally only see a debris signature on the WSR-88D in association with a tornado of high-end EF3 to EF4 intensity or greater (roughly 150+ mph surface wind speeds). 

The above image was taken from the Dual-Pol radar at the NSSL radar testbed in Norman, OK.  The white and pink colorations within the white circled area on the image shows where the Dual-Pol is detecting tornadic debris.  This debris field was not as easily identified on conventional radar.   Of course, you must also keep in mind that the tornado, regardless of strength, would have to be in an area where debris could be picked up before the radar would be able to see it.

Dual-Pol technology is likely to be of particular help in the tornado warning process in 2 specific areas:  (1).  when the circulation is rain wrapped and not easily visible by storm spotters and (2).  when the circulation is occurring at night and not easily visible to storm spotters.

The system will also be a big help with non-precipitation events as well.  Because it takes a more detailed "slice" through the atmosphere, Dual-Pol technology will be able to forewarn of local hazards near the radar site, like dust storms for example.  Below is an image taken by the Dual-Pol radar near Phoenix, Arizona this past Tuesday, July 5th:

The red dashed line notes the leading edge of a wall of dust that was advancing toward the city from the South.  Here is what that advancing dust cloud looked like outside the National Weather Service office:

The enhanced scanning of the atmosphere very near the earth's surface by the Dual-Pol radar will allow it to detect very small particles, like the dust particles above, as well as insects, birds, etc., close to the radar site.  The WSR-88D is already able to do this to some extent, but the resolution and detail of such scans will be even greater with the new Dual-Pol technology.

Now that we have a few Dual-Pol radars online and others being added about every 2 weeks, I'll be posting some images of the new technology in action, and comparing it to the old where possible.  Stay tuned!

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The Tornado Chronicles: Dexter and Ida, MI Area Tornadoes of 3-15-12...

***Update, 3/16/12, 3:45pm CDT:
The National Weather Service (NWS) has completed their survey of the Dexter area tornado and have rated it EF-3 intensity with maximum winds estimated at 140 mph.  They note a path length of 7.2 miles with a maximum damage path width of 800 yards.

Frankly, I was fully expecting the EF-3 rating by the NWS, however I think they missed something.  The preliminary report states "the most intense damage included houses destroyed with some interior rooms remaining".  The following screen grab from a video that was added to this post at the 7:25pm CDT update yesterday clearly shows a home with no walls - interior or exterior - remaining:

Though isolated to the single home above, that is EF-4 intensity damage (defined as no interior or exterior walls remaining).  You can see what I'm talking about in even greater detail when you watch the video.  The above home comes into view at approximately 40 seconds in.  Scroll down to the 7:25pm CDT update (below) and you can view it in its entirety.

I do agree that most of the remaining damage shown here and elsewhere is of no greater than EF-3 intensity.  It's hard to know whether the survey team actually saw the above home today, or if they did but assumed that some sort of demolition had taken place since yesterday afternoon.  The helicopter footage was in real time right after the tornado took place, so we know that the damage was caused by the tornado and not by any human intervention.

With all of the above said, I am still amazed, and very thankful, that no one was injured and there were no fatalities from this event!

There are still additional surveys to come, with one or more tornadoes likely near the Ida area as well.  We'll post updates on that as they become available...  

***Update, 3/16/12, 11am CDT:
A couple of new videos of the tornado near Dexter have emerged overnight and early this morning. This first one captions the tornado as "F3" - which is premature as the damage survey is only getting underway today.  As I pointed out in a video yesterday (see 7:25pm CDT update), there was apparent EF-4 damage to at least one home based in that video.

Anyway, here is the first of the new Dexter tornado videos.  Lots of yelling but I don't believe any bad language:

The next video, also from the Dexter area, shows a well developed tornado initially, then we appear to be witness one of the many transitions that were observed on radar where the circulation weakened and then reformed:

A couple of very telling damage photos via the Associated Press from the Dexter area:

...and one (same source) from the Ida area:

***Update, 8:25pm CDT: Very brief video of the Dexter tornado taken from Mast Road North of Huron Parkway:

...and from the same videographer taken from Mast Road to the South of North Territorial Road:

This very short video below shows damage in the Huron Farms subdivision. Another, more lengthy, video of damage in this area is shown further below at the 7:25pm CDT update:

***Update, 8:10pm CDT: Dexter, MI is located in Washtenaw County. Since at least 1950, this appears to be the earliest tornado event to ever occur in the region.  The previous earliest tornado of record took place on April 3, 1988 (which also means that today's event includes the first recorded tornado in this area during the month of March).  

Also, please note the additional comment added to the damage video in the update posted at 7:25pm CDT.  One home in that video has no walls remaining.  Depending on the construction of that home, this would suggest either EF-4 or very high end EF-3 damage.


***Update, 7:50pm CDT: Another photo of the tornado near Ida, MI (photographer unknown - via twitter):

***Update, 7:25pm CDT: The following damage and tornado videos have recently been posted from the Dexter, MI area.  In the first video, note that there are no walls remaining on the home shown at approximately 40 seconds into the video.  This implies at least EF-3 and possibly EF-4 damage (depending on the construction):

Media reports indicate that at least 200 families have been displaced in the Dexter area.  A temporary shelter has been established at the Mill Creek Middle School.

------------------------------------Prior Updates Posted Below:

***Update, 7:10pm CDT:  Another YouTube video has emerged of the Dexter, MI tornado (above).  

***Update 6:25pm CDT: The above photo was taken near Ida, MI, where numerous reports of damage have been received. Photographer unknown. If you took this photo and wish to be credited (or have the photo removed), please e-mail me.  

The following photo also appears to be near Ida and was taken by Kylie Desmond:

***Update 5:45pm CDT: The following YouTube video has emerged showing the tornado near Dexter, MI at the Hudson Mills Metro Park. WARNING FOUL LANGUAGE THROUGHOUT:

Please note, I am no longer "live blogging" the progression of the parent thunderstorm.  I will, however, be updating this post with photos and videos of the tornadoes and damage throughout the evening, so please check back for updates...

***Update 5:30pm CDT: Two more photos of the tornado near Dexter, MI from twitter follower @laurenluvsjeeps:

***Update 5:25pm CDT: A photo of residential damage has come forward from the Dexter area:

Meanwhile...the storm continues moving Southeast.  The circulation as indicated on radar has reorganized back to the South a bit over the last 10 minutes, and is now located just to the North of Saline:

Folks in and near Saline, Stony Creek and Milan should take tornado precautions until this storm passes.  This storm has a history of producing tornadoes and damage.

***Update 5:05pm CDT: The following photo of the tornado was reportedly taken just North of Dexter, MI and was just posted on storm chaser Nick Nolte's facebook page:

I realize the copyright stamp says 2011, however you can see that the photo was just posted on facebook by going to the link.  I can also see Nick's GPS signal on radar near the storm as well, so he is definitely chasing it at this time.  So, we will assume the above photo is "real" until we receive information that suggests otherwise.

Update, the photo was current.  Below is an even better one taken by Nick.  Please visit his website at www.nicknoltewx.com for outstanding storm photos and videos:

Also, you can go to this link for another view of the tornado as taken by a resident of Dexter and provided to ABC7 News.

The circulation has weakened considerably on radar recently, however considering this storm's history it would be wise for folks in Barton Hills and Ann Arbor to stay in shelter until the storm passes.

---------------------------------------------Prior update:

***Update 4:50pm CDT: Tornado damage has been reported in the Dexter area. The circulation on radar continues to move toward the Southeast at about 15-20 mph...

This circulation is moving in the general direction of Barton Hills and Ann Arbor.  If you live in these areas, stay in shelter until the storm passes.

This is not the time to be driving home from work in this region either.  Stay inside a safe place until the storm passes.

---------------------------------------Prior update below:

***Update 4:40pm CDT:  The circulation on radar (above) is not quite as strong, but is still evident just to the North of Dexter.  The storm is moving Southeast at 20 mph.  If you live in Dexter, Barton hills, Ann Arbor or surrounding areas, stay in shelter until this storm passes.  

Hail up to golfball size is also possible, mainly to the North of the area of circulation.

--------------------------------------Original post below:

The above image was just taken from the Detroit area radar.  The left half is the radar in reflectivity mode (rain, hail, etc.) and the right half is the radar in velocity (wind speed and direction) mode.

You can see a severe thunderstorm to the West of the City (Detroit is located at the center right of each of the split screens) and moving Southeast at 15-20 mph. I have circled the tornadic circulation on the velocity image in yellow.  You can also see the classic "hook echo" signature on the reflectivity image.

If you live in Dexter, Barton Hills, Ann Arbor, Worden and surrounding areas, seek immediate shelter!

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Interesting Look at Rotation on Tuesday Night / Wednesday Morning's Storms...

The above image was provided by the NOAA Environmental Visualization Laboratory (EVL). It shows the output of a computer algorithm which attempts to identify where rotation in a storm (as indicated on area radars) may be strong enough to produce a tornado on the ground.  The algorithm uses a combination of wind and hail data to arrive at its conclusions.  This particular image shows the output of that data for the storms of Tuesday evening (February 28th) and early Wednesday morning (February 29th) of this week.

I have taken the same image and added the locations of the 4 cities that were hardest hit by tornadoes that night:  Branson, MO, Buffalo, MO, Harveyville, KS and Harrisburg, IL (click to enlarge):

A scale isn't provided, however the lightest shadings indicate the weakest rotational/tornado signature, and the darkest indicate the strongest signatures.

As you can see, the storm responsible for producing the Branson area tornado actually began rotating as it moved through Tulsa, and continued doing so all the way across the southern edge of Missouri and into extreme southern Illinois and extreme southwest Kentucky!

The storm responsible for the EF-4 tornado in Harrisburg, IL began showing strong rotation over southcentral Missouri (to the Northeast of the Branson storm).  

Both the Buffalo, MO and Harveyville, KS storms also showed relatively strong signs of rotation on radar well before they actually produced tornadoes on the ground (yet they too did not produce a tornado for the entirety of the rotational cycle).

Herein lies the challenge to the meteorological community:  lots of severe storms rotate, but not every rotating storm produces a tornado on the ground.  To further complicate matters, we have yet to establish any type of rule of thumb that says something like "a storm rotating at such and such velocity will generally produce a tornado 90 minutes after it starts rotating..."

This problem is by no means new, yet it is one that needs to be solved quickly in order to improve the current tornado warning system.  Until then, you are likely to continue to feel "overwarned" from time to time as meteorologists struggle with when to issue a tornado warning based off of radar with no ground truth data available to support the decision.

One step in the right direction is the ongoing upgrade of existing NWS radars to dual polarization technology.  You can see my post here for more details on what that technology promises to bring.

The Springfield, MO radar (which is the site nearest Branson) had the new upgrade in place prior to Tuesday's storms.  The output from that radar clearly showed a strong signature of tornado debris as the storm moved through Branson on Tuesday night:

Branson is located near the center of the image.  The dark blue and light green pixels indicate the presence of the debris associated with the tornado that was ongoing at the time the image was taken.

If you've been reading the blog for very long, you know that it's not unheard of for a debris ball to show up on radar (even before the upgrade).  What is unusual about the above image taken by the new technology on Tuesday night is that the Branson tornado was "only" rated EF-2 intensity.  In the past, with the old technology, a debris ball would not typically show up with a tornado that "weak" (most of the tornado debris ball signatures we saw last year with the old technology were EF-4 intensity or higher).

The ability to potentially detect the debris signatures of weaker and/or shorter lived tornadoes is a very promising advancement, indeed!

Several of the radars in the areas to be affected by severe weather tomorrow have recently been upgraded to the new technology as well.  I plan to monitor that new data tomorrow evening and will be sure to post any interesting findings...

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We're Going 'Batty' In Austin....

A friend of mine sent me a picture of a bat that took up residence on his back porch this morning (see image below):

We both live near Kyle, TX, just South of Austin.  You may have heard of the "Batfest" that takes place in Austin every year, underneath the Congress St. bridge downtown.  In fact, it's going on this weekend.  When I got my friends picture, I jokingly said that the bat probably got lost on the way back from Batfest last night...

In the past I've noticed flocks of bats show up on the New Braunfels doppler radar, usually rushing out of some caves between here and San Antonio at dusk, so I thought it would be cool to watch the radar this evening and see them fly out of the Congress street bridge in Austin.  (Yes, what is "cool" to one may not be "cool" to another, but you've got to consider the source here).

Well, much to my surprise, not only did they fly out of the Congress street bridge at about 8:10pm, but also out from under a bridge a mere 1/2 mile from my house.  That explains the mystery bat, for sure...

Take a look at the radar images below.  I've circled 3 bat swarms on the images.  The first image was taken at 8:10pm, and the 2nd at 8:14pm: 

The phenomenon looks even better in an animation if you have GRLevelX or some other kind of radar software (the higher resolution the better - this stuff doesn't always show up on the mass-media radar loops).

The Northern-most swarm is the Congress bridge, the middle one is a bridge that goes over Onion Creek in south Austin, and the bottom one is the bridge near my house (Kyle Parkway bridge).

Doppler radar is sensitive enough, when other atmospheric conditions are right, to pick up things like bird (and bat) flocks, and sometimes even insects.

Hmmm....I might have found a business opportunity here.  "Kyle Bat Fest", here we come...

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Radar Imagery Associated with the Indiana State Fair Stage Collapse

The purpose of this post is to show you some of the radar images associated with a line of thunderstorms that caused the tragic stage collapse yesterday evening at the Indiana State Fair.  For more specific details on the event itself, as well as my thoughts on how this tragedy could have potentially been avoided, please see my earlier post.


The first image was taken at 8:35 PM EDT by the National Weather Service (NWS) Radar in Indianapolis.  This was about 4 minutes before the official NWS warning was issued:

I have put a red dot on this (and subsequent) images showing the location of the Indiana State Fairgrounds.  On this first image I have also circled it in yellow (look near the center of the image under the word "Rocky".

The white arrows on the above image note the location of a "fineline", the thin blue line that you see (dotted in some areas, more solid in others) out ahead of the line of thunderstorms that were advancing toward the East at 25-30 mph.  A fineline is a radar signature that denotes strong, gusty winds (also known as a "gust front") blowing out ahead of a line of storms.  In this particular case, the gust front was approximately 5-7 miles out ahead of the line of storms on the Northern end (which is the portion that would have affected the Fairgrounds).

By the 8:44 PM image (below), the gust front was about 4 miles West of the Fairgrounds and continuing Eastward:

In just that 9 minute period of time, you can see that the fineline/gust front signature on the radar has advanced even further ahead of the thunderstorm line to the West of the Fairgrounds - a sign that the winds were growing stronger and advancing further East of the thunderstorm line at an even faster rate.

By the 8:53 PM image, the gust front was on top of the Fairgrounds, with the radar signature having advanced just to the East of that location: 

As I pointed out in my original post, a trained professional would have recognized the fineline/gust front signature on radar, as well as its Eastward acceleration, and the obvious danger that it posed to the Fairgrounds.  

The viewing of a radar image on a smartphone by a non-trained individual (see my original post for those details) simply doesn't get the job done, and carries potentially disastrous consequences as we've unfortunately seen in this case....

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Very Large Hail East of New York City Today...

The above video was captured about an hour ago by a resident of New Hyde Park, NY, on Long Island, about 25 miles East of New York City. As you can see, hailstones of quarter to tennis ball size can be seen plopping in the pool and on the porch!

The radar image below shows the storm responsible for the very large hail earlier in New Hyde Park.  It is currently drifting slowly toward the Southeast:

The left half of the image shows the radar in "reflectivity" mode (i.e., rain, hail, etc.), while the right half shows the radar's VIL "vertically integrated liquid" mode.  As a general rule, the higher the VIL value (i.e. the white and grey colors on the image), the larger the hail.

Jump back to 4:20 PM EDT, which is about the time most of the large hail was falling in New Hyde Park, and you can see what the VIL image looked like at that time:

The green triangle just to the right of "New Hyde Park" on the image is where the radar was estimating 2.5 inch diameter hail was falling at the time.  Turns out the radar was "right on" in this case....

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A Tornado Warning in a Very "Unlikely" Place...

A Tornado Warning was recently issued on this storm between Houlton and Presque Isle, Maine. Yes, I said Maine. No ground-truth reports yet, and the wind velocity (wind speed & direction)  mode of the radar (see below) tends to indicate strong, gusty winds blowing out of the storm rather than pronounced rotation.  With that said, brief (and generally weak) tornadoes sometimes spin-up on the leading edge of such storms...

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Radar Imagery Associated with the Joplin Tornado of 5-22-11

This article will present a series of radar images depicting the supercell thunderstorm that produced the devastating EF-5 tornado in Joplin, MO on May 22, 2011.  The vantage point is from the NWS radar near Springfield, MO (about 55 miles to the East/Northeast).


First, a little radar refresher course for our newest readers.  I'll be showing two types of radar images:  Base Reflectivity and Storm Relative Velocity.  Base Reflectivity images show the radar's depiction of rain, hail (and as you'll see in some images, debris), being reflected back to the radar.  Storm Relative Velocity images show the wind speed and direction within the thunderstorm, as estimated by the radar.


When examining the storm relative velocity (SRV) images, keep in mind that the red colors depict wind motion away from the radar site, while the green colors depict wind motion toward the radar site.  In this case, the radar site is located off of the images, toward the East/Northeast (or upper right).


Now that we have the basics out of the way...lets take a look at the images from that fateful day back in May...


The first series are Base Reflectivity images, starting at 5:34 PM CDT and ending at 5:58 PM CDT.  The interval between each is about 5 minutes.  Joplin is located just to the right of the center of each image (click to enlarge):

Reflectivity image at 5:34 PM CDT

Reflectivity image at 5:39 PM CDT

Reflectivity image at 5:43 PM CDT

Reflectivity image at 5:48 PM CDT

Reflectivity image at 5:53 PM CDT

Reflectivity image at 5:58 PM CDT

As you can see, a pronounced "debris ball" becomes visible at about 5:43 PM CDT, as debris is being lifted aloft and carried away by the tornadic storm.  I've annotated the debris ball with a white circle in the images below:

Reflectivity image with debris ball at 5:43 PM CDT

Reflectivity image with debris ball at 5:48 PM CDT

Reflectivity image with debris ball at 5:53 PM CDT

The next series of images shows the same radar in Storm Relative Velocity (SRV) mode, at the same times as the above reflectivity images:

SRV image at 5:34 PM CDT

SRV image at 5:39 PM CDT

SRV image at 5:43 PM CDT

SRV image at 5:48 PM CDT

SRV image at 5:53 PM CDT

SRV image at 5:58 PM CDT

As you can see, the tornadic signature was initially moving East/Northeast and then turned more toward the East and then Southeast after crossing Highway 71 on the East side of Joplin.  This corresponds well with the ground-truth damage survey as completed by the NWS:

Values inside the triangles correspond to EF intensity

I'll explore the change in track in greater detail in a later post dealing with the damage assessment as related to radar and satellite imagery.

Remember earlier when I pointed out that greens show the radar's estimation of wind blowing toward the radar site and reds show the wind blowing away from the radar?  This is where we put that knowledge to use.  I have taken the same SRV image shown above from 5:43pm and circled (in white) the rotation couplet as indicated by the radar in the image below:

Rotational couplet on radar peaked at 5:43pm CDT

At this point, the radar was estimating that wind speeds at the center of the white circled area were approximately 141 mph toward the radar and 69 mph away from the radar, for a total "shear" (or opposing wind motion) value of 210 mph at that point.  It's important to keep in mind that the thunderstorm and associated tornado were about 50-55 miles from the radar site near Springfield at this point.  At that distance, the radar was scanning the storm at a level between 4,000 and 4,500 feet above ground on the above image.  Even with that in mind, the total wind motion value of 210 mph as estimated by the radar corresponds quite well to the ground-based storm survey which indicated damage consistent with winds in excess of 200 mph in this region.

You may have also noticed the small red "plus sign" and the small yellow dot located near Joplin on the above images.  The red plus sign corresponds to the location of Sam's house, and the yellow dot corresponds to the location of Joplin High School.  I thought it would be interesting to zoom-in at street level on a couple of selected radar images and take a look at how the radar signatures correspond with those hard-hit locations.

First, the Storm Relative Velocity (SRV) image at 5:39pm CDT, which shows the tornadic circulation growing stronger as it approaches Sam's neighborhood and the Main Street corridor.  At this point, the radar was estimating 148 mph of total wind motion near the circulation center:

Zoomed-in SRV image at 5:39pm CDT with rotation noted

By 5:43pm CDT, just 5 minutes later, a pronounced debris signature was noted on the reflectivity image, extending just over 1 mile across, as debris was being lifted and carried aloft by the tornadic thunderstorm:

At the same time, the corresponding SRV image estimated 210 mph of wind motion in association with the circulation center, just to the East of the High School:

The satellite image below is zoomed-in on the same general area as shown above.  You can see the level of destruction that took place along the path of the strong circulation center.  The brown "swath" of damage in the satellite photo is about 1 mile wide on average, which also correlates quite well to the radar signatures above.  I've added notations of the High School and Sam's House as further points of reference: (click to enlarge):

I'll be taking a much closer look at the damage as detailed by satellite and other imagery (photos, video, etc.) in an upcoming post on the damage assessment.  I also plan to match-up some additional close-in radar images to correlate with the damage imagery as well.

For more on the Joplin tornado event, click here to return to the table of contents post, which contains a chronological listing of all related posts, and will be updated with new links as additional posts are made.

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