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The Oklahoma tornadoes: a view from space

NASA's Earth Observatory released an animation of images taken by the NOAA GOES-East satellite yesterday, as storms raged through Oklahoma far below.

They have a terrible beauty to them, knowing what was going on underneath the clouds, but for people looking for more information about the hows and whys of tornadoes, watching them from above can show the ingredients that went into making the deadly storms.

[ Related: Monster tornado tears through southern Oklahoma City area ]

Let's break that down.

This first time step, around 11 a.m. local time, shows the flow of moist air coming north off of the Gulf of Mexico — you can see that in the streaks of clouds over Louisiana. You can also see how over north central Texas and south central Oklahoma, they're getting some morning sunshine. Warming the surface like this is an important part of developing the unstable conditions that will generate storms later on.

In this second still, you can see the beginnings of a line of clouds over central Oklahoma and Texas. Notice how the sky to the west of that — going into the Texas Panhandle — is pretty clear. You can see right to the ground. That shows that the line of clouds developing is along the 'dry line' — the boundary between the moist Gulf air and the drier air that's had its moisture wrung out going over the Rockies and is now flooding into the western Plains. In the animation, you can also pick out so-called 'jet streaks', where the clouds are being pushed along at upper levels by the jet stream over Oklahoma. This will also add fuel to our storm's fire.

And boom, there we go. Right around 2 p.m. local time, we see the first thunderstorms firing up along that dry line — if you can't spot them, the anvil storm clouds are the puffy blobs forming over south-central Oklahoma. The instability built by the sunny morning, moist Gulf air and cooler, drier air flooding in from the west has finally become strong enough that large anvil clouds (thunderheads) can form.

This is around 3 p.m. local time, right around when the killer tornado is shredding its way through Moore, OK. That storm cell is one of three very pronounced, very tall anvil clouds over the state. If you look closely at the still, you can see the little 'bump' on the lower left-hand side of each cloud mass that indicates the area of strongest updrafts — where the clouds are poking up the highest.

By the time we get to about 5 p.m. local time, you can see the mass of clouds has spread and deformed into one long band, rather than the individual storm cells we saw to start. This is due to the wispy 'cirrus' clouds spreading out from the top of each anvil having joined together as the storms aged. However, you can still see a 'stripe' of 'graininess', from northeastern Oklahoma to northern Missouri, as new storm cells develop where the older ones have dissipated.

In the last shot, storms continue over Oklahoma and northern Texas, but you can also see how the line has expanded up into Missouri, and the textured 'bumps' in the cloud are the hallmarks of other severe storms further north.

[ More Geekquinox: The science of tornadoes: How and where do they form? ]

There's a serene quality to images taken from that far away, that belie the devastation caused by these storms, but satellite images are an indispensable tool for forecasters and atmospheric scientists in their goal to understand how these events happen, and to protect people as best they can.

(Video and images courtesy: NASA Earth Observatory)

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