26 miles away in lake thunderbird Oklahoma. So Sam tell us more about this massive tornado. I die I'll tell you this is an incredible sight isn't the third day by the way that violent storms have been... See More
26 miles away in lake thunderbird Oklahoma. So Sam tell us more about this massive tornado. I die I'll tell you this is an incredible sight isn't the third day by the way that violent storms have been in this area in the third day. Seems to have dropped the worst tornado of the -- Doubt we will show you some pictures from storm chaser video as we talk about this the National Weather Service has this storm right now at a preliminary. Copycat category here as an EF -- this is rarefied territory for tornadoes there are some reports this thing was on the ground for forty minutes covering twelve miles -- that time. There are some reports that day on the ground. This tornado was about two miles wide and we won't know until we can get -- and look at the debris field there. You can see the tornado filling the sky. Another amazing thing about this tornado is on the radar would have first popped out -- new castle and by the -- -- is being called the New -- more tornado because it started. In -- accountable when it dropped out it was just a finger. Of a tornado barely a funnel cloud but within an hour it became this monster storm that was roared -- -- just about as quickly. As all the details have told us that Joplin storm developed so. We'll show you some aerials of the damage now because this storm. Has been covered with Storm Chasers and local television from start. To finish and now you're looking at the rubble the unbelievable debris field you heard ginger in the field walking around there. And we've heard reports that some of the foundations were completely cleared and that puts it definitely -- that EF four it may be even higher. Category -- it's capable of taking a foundation and clearing -- of debris as the storm leaves the area so it looks like it's been swept already. By a big tractor but it hasn't been yet it was just the storm that did that damage and other areas. Buildings just shattered then you look at major construction and you see major cement construction. Also being damaged this is very unusual in the signature of a very large and very powerful tornado. Folks have been digging through the debris and lifting up these heavy pieces of -- debris whether it's wallboard or siding or roof they. A twisted metal trying to find -- anyone who might still be in the rubble all of this is going on because this is still. A very large area and from the sky you can see it's house after house after house in neighborhoods this is a growing neighborhood that's just south. Of Oklahoma City. Very large area of homes very large residential area with lots of homes and -- homes. Businesses. Hospitals. All just bite taken out by this one storm something that -- I gotta tell yet. I haven't really seen anything like this and I don't like to compare storms too much but sometimes you just look at the damage -- you -- -- it reminds him another storm and the storm is reminding us a lot of Joplin Diane that is not a good thing. Thank you so much -- it reminds us again how important the warning system isn't by some accounts there were twenty. To thirty minutes when the sirens sounded for everyone to try to get to some kind of shelter.
This transcript has been automatically generated and may not be 100% accurate.