Original subtitles

[ whirring, electronic beeps ]

Narrator: worldwide, 300 Million surveillance cameras

Are watching us on our streets,

At work, and in our homes.

They capture things that seem impossible.

It defies the laws of physics.

Man: oh, this is unbelievable, man.

Narrator: experts carry Out forensic analysis

On these unusual events.

There's got to be some Explanation for what's going on.

[ people screaming ]

[ electronic beeps ]

Narrator: coming up, a dash cam reveals

A flesh-and-blood monster... [ screech ]

It does not fit any animal

That we have in our d.N.A. Bank. [ growls ]

Narrator: sinister acts of a Potential paranormal presence.

This spontaneously exploding pint

Has all of the hallmarks of a poltergeist.

Narrator: unidentified columns of darkness

Descend on a city.

I remember looking out The window and thinking,

"Something wicked this way comes."

Narrator: and scientists investigate

A terrifying explosion in the night sky.

Has it all gone south, and this is it?

This is the big one?

[ explosion ]

[ electronic whirring ]

Narrator: bizarre phenomena,

Mysteries caught on surveillance,

What's the truth behind This strange evidence?

[ growl ]

Narrator: an american monster hides out

In southern pastures. [ growling ]

Farm animals drained of Blood, fang marks on their neck.

Narrator: many believe tales Of a vampire dog are a myth

Until something strange Is captured on camera.

It is the most unusual animal

That I have ever seen in my entire life.

This thing is on the loose in texas.

[ growling ]

♪♪

Narrator: in southern texas,

Sheriff jode zavesky's police department

Presides over a remote, rural area.

♪♪

Dewitt county is a large County, 910 square miles.

There are a lot of uninhabited Areas of the county.

The more the population spreads out,

You begin to see more of These animals or creatures

That you didn't really know inhabited

The same county you did.

♪♪

Narrator: on august 8, 2008,

Two deputies are on a routine patrol

Down a country road.

Their dash cam captures a bizarre creature.

♪♪

This animal is a little Bit more than weird.

It's unnatural. They did Not know what it was.

♪♪

Narrator: it seems doglike,

But this misshapen animal

Is no ordinary canid.

It almost had an alien look to it.

It's got pointed ears That stick up atop its head.

It's got an elongated snout, Fangs, protruding canines.

First instinct is to be repulsed.

♪♪

Narrator: the deputies believe this is

Evidence of a legendary, Blood-sucking vampire dog.

♪♪

[ electronic beeps and whirs ]

♪♪

In south texas, this close to mexico,

There has always been Legends of different animals.

We have this mythical Creature called a chupacabra.

[ growls ]

Narrator: descriptions of the chupacabra

Vary throughout the americas,

But in texas, it takes The form of a hideous,

Blood-sucking hellhound... [ growling ]

With a growing reputation.

More and more stories came Out about these livestock

That were killed in the strange manner

And these were all Attributed to el chupacabras.

Narrator: and there is Strange supporting evidence

That a bloodsucking Monster is terrorizing texas.

[ electronic beeps and whirs ]

Nutritionist dr. Phylis canion Owns a ranch in dewitt county.

In 2007, an unidentified beast Slaughters her livestock.

Its method of attack... Is chewing.

Whatever was getting in Was just killing one chicken

And leaving it, always Open up in that thorax area,

And that's where they Would lick all the blood out.

Never touched the meat.

They were just sucking All the blood out of it.

Narrator: experts acknowledge That on rare occasions,

When something spooks a predator,

It may leave similar bite marks.

What happens is a dog or Coyote will attack an animal.

They'll bite it on the neck, And then they'll run away

And the animal will die From internal hemorrhaging.

[ growling ]

Narrator: but on phylis canion's farm,

This is not a rare event.

It's a persistent way of feeding.

It happened through 28 chickens.

28 chickens were identical.

It craves blood and not the meat.

Narrator: the vampire beast Stays in the shadows...

♪♪

...Until phylis has a close encounter

With the macabre creature.

♪♪

Something caught my eye,

And when I looked over... I am shocked.

I've seen a lot of Things, but I've never seen

An animal that looked like that.

Narrator: the chance sighting leads phylis

To a chilling conclusion.

Whatever it was that I was Seeing, was killing my chickens.

[ growls ]

[ electronic beeps and whirs ]

Narrator: the sheriff's department hears

Of phylis' sightings

And shows her their video for comparison.

The creature she saw in her pasture

Exactly matches the beast on the dash cam.

♪♪

That moment that it looks to the side

Was the icing on the cake.

The top mandible was longer Than the bottom mandible,

And it was very evident it Is the most unusual animal

That I have ever seen in my entire life.

Narrator: dr. Canion makes it her mission

To identify the bizarre beast.

I didn't know what I Had seen. I had no idea.

Whatever it is, I'm going to find out.

[ electronic beeps and whirs ]

Narrator: investigators Study the video's details

To try to explain the bizarre creature.

One freakish feature of the beast

Is its strange, hairless hide.

It was kind of a bluish-gray, And it looked like

You were looking at the Skin of an elephant on it.

It looked rough and...

Narrator: at first, researchers Suggest the lack of fur

Could be consistent With a parasitic infection.

Animals get what's called mange,

And it's a skin disease caused by mites.

♪♪

The mange mite burrows down in the skin

And actually makes the Hair fall out in little areas

And the skin kind of crusts over.

But a skin infection Cannot explain the other

Distinctive features in the footage.

It turns its head to the side And its profile is really weird.

This thing is strange.

[ electronic beeps and whirs ]

♪♪

Narrator: searching for answers,

Investigators speculate If the beast's appearance

Could result from modern farming methods.

♪♪

Chemical contamination Can artificially alter genes.

There are chemicals that,

If they're exposed to growing fetuses,

Can cause mutations and cause The offspring to be a mutant.

[ heart beating ]

Narrator: could the vampire beast

Be a man-made abomination?

♪♪

[ electronic beeps and whirs ]

Coming up, something huge Emerges from the dark horizon.

Out of this void

Comes this tremendous, Quickly growing sphere.

Narrator: doom-laden skies Seem to herald the apocalypse.

Buildings just come apart dramatically

As they face the onslaught Of tornadic force winds.

[ thunderclap ]

[ electronic beeps and whirs ]

Narrator: and the texas Vampire gives up a vital clue.

I had the d.N.A., and as I sat there

And read it, I was totally amazed.

♪♪

♪♪

Narrator: researchers struggle To explain dash cam evidence

Of a bizarre predator in texas.

♪♪

Some suggest the beast may be A victim of a chemical mutation.

We do live in a farming and ranching area

In this part of south texas.

There are chemicals that are put out

That some animal could Come into contact with.

Perhaps the creature in this footage

Is the product of some mutation From when it was in the womb.

♪♪

Narrator: chemical mutations can create

Nightmarish deformities,

But rather than showing signs Of a debilitating birth defect,

The texas vampire seems to be thriving.

♪♪

It's clearly well adapted To the environment

And is a very fast predator...

Able to avoid people And still find enough food

And therefore pass their Genes on to the next generation.

[ electronic beeps and whirs ]

Narrator: experts remain puzzled,

But a phone call finally Gives dr. Canion a chance

To identify this blood-thirsty predator.

♪♪

The chupacabra met its Demise when somebody hit it

With a car on the highway.

The flesh and blood Version of a mythical beast

Is now in her grasp.

I can actually start to study It and figure out what it was.

Narrator: to get an accurate reconstruction

Of the beast's bizarre features,

She hires a taxidermist, And the result reveals

A frankenstein combination of animal parts.

[ growling ]

[ screech ]

The texture of the skin reminds me

Of some type of an elephant hide.

♪♪

The forehead width is that of a wolf.

The bottom mandible Is about an inch shorter

Than the top mandible.

♪♪

[ growls ]

When we look at the animal

And we put all of these Abnormalities together,

The mystery still is, "What is this?"

[ growls ]

[ electronic beeps and whirs ]

Narrator: but phylis now has access

To the beasts' genetic blueprint.

Veterinary forensics experts At u.C. Davis in california

Process a cell sample...

And send back the results.

♪♪

I had the d.N.A., and as I sat there

And read it, I was totally amazed.

♪♪

They said, "It does not fit any animal

That we have in our d.N.A. Bank."

It had coyote on the maternal side

And mexican wolf on the paternal side.

[ growls ]

Narrator: the mythical chupacabra exists

As a strange hybrid beast

With an apparent thirst for blood,

And this specimen's not The only one out there.

♪♪

A growing number of sightings Suggests it's invading america.

There may be 10, 15 hundreds of Them running around out there.

Who knows in the remote Areas of the county?

I got a picture from florida of one

That was dead along the side of the road,

And I will tell you it Looked exactly like mine.

♪♪

[ electronic beeps and whirs ]

Narrator: and now... ♪♪

A space observatory Captures an unearthly presence

In the night sky.

♪♪

This rapidly expanding,

Glowing orb grows out of the horizon line.

Something is happening That's incredibly powerful.

Narrator: the unknown Force defies explanation.

Maybe the camera captured something

We weren't meant to see.

This is not natural...

And there's no people out there to make it.

♪♪

[ electronic beeps and whirs ]

Narrator: in hawaii,

The world's largest Astronomical observatory

Searches deep into the night sky

To unravel the mysteries of our universe.

Mauna kea observatory has, at its height,

Some of the world's darkest, driest air,

And it allows us to get close to the stars

With our optical telescopes.

To help us watch over those telescopes,

We have a whole slurry Of different webcams,

Pointed in all directions.

[ electronic beeps and whirs ]

Narrator: the total optical power

Of the mauna kea telescopes

Is 60 times greater than The hubble space telescope.

But on june 22, 2011,

It's a simple surveillance Camera trained on the horizon

That captures a bizarre event.

You're just looking out at stars.

You're seeing the night Sky. It's pretty calm.

Everything seems Peaceful. Nothing is moving.

All of a sudden, out of this void...

♪♪

...Comes this tremendous,

Quickly growing, inexplainable sphere.

A vast amount of power has been released.

It makes you feel more than small.

It makes you feel scared.

Narrator: hawaii lies isolated In the middle of the pacific.

Experts question who Or what can be producing

This terrifying spectacle.

This is not natural and there's No people out there to make it.

So what could this conceivably be?

[ static ]

Narrator: coming up, an age old building

Hosts unseen destructive forces.

The energy is so strong that The glass is turned almost to dust.

[ electronic beeps and whirs ]

Narrator: and suspicious circumstances

Surround the strange orb over hawaii.

This is 3:36 in the morning.

A really good time for testing things

That you don't want people to see.

♪♪

[ static ]

♪♪

Narrator: a mysterious expanding orb

Fills the night sky over hawaii.

♪♪

Initial investigation Suggest an object from space

Could be behind the phenomenon.

Something is coming in from Deep space, hits the atmosphere

Moving at thousands of miles per hour.

There's only so many things That are moving that fast

Through the sky.

One of them could be a meteorite.

♪♪

Narrator: when a large space rock

Enters the atmosphere,

It can trigger an air burst.

An air burst occurs

When something passing Through the atmosphere

Rather than continuing to come through

Like a spacecraft would, explodes.

♪♪

Melting rock, perhaps Melting ice within the meteor

Suddenly expands and explodes And blows the thing apart

Into this sort of spherical star burst.

Narrator: but closer Analysis shows key evidence

For a meteor is missing.

You'd expect to see more Of a... Kind of a fireball

That then explodes.

This did not look like an air burst.

[ electronic beeps and whirs ]

♪♪

Narrator: if the phenomenon Is not from space,

It must originate on earth.

Researchers believe the Time and place of the event

May be significant.

Hawaii is very isolated.

It's in the middle of the pacific ocean

So it's the perfect place for testing.

So this is june 22nd, 3:36 in the morning.

A really good time for testing things

That you don't want people to see.

Narrator: investigators Consult star maps to determine

The direction the Surveillance camera is facing.

You can see constellation cassiopeia.

That indicates the surveillance camera

Is pointed to the northeast.

We know that we're Looking towards california

Where we have multiple military bases.

Narrator: it makes investigators wonder

If some form of covert operations

May be behind the mysterious expanding orb

On the surveillance camera.

The u.S. Military seek isolated Regions for clandestine tests

Of top secret war planes.

A fully armed supersonic aircraft

Ripping through the edge of space

Could generate a powerful shock wave.

Aerospace researchers are Obsessed with shock waves

Because a shock wave at The tip of an aircraft causes

When it's moving extremely fast

And that radiates out from The tip in a circular fashion.

People maybe see an aircraft Going through the speed barrier.

Narrator: but there's a problem

With the idea of the supersonic shock wave.

That expanding shock wave Isn't lighting anything up.

Whatever this was lit things up.

So there must be something else.

It looks more like an explosive event.

Has some kind of bomb has blown up?

[ electronic beeps and whirs ]

Narrator: investigators dig Deeper to try to pinpoint

The exact source of the explosion.

On the internet, people start Sticking into this problem.

There was a missile shot taken At vandenberg air force base

That night and yes, it would Be crossing that part of the sky

At the time that the anomaly was seen.

It could be an explosion of A missile that was launched.

Narrator: the vandenberg air base

Has a key role in u.S. Defense.

It's home to some of the most

Devastating weapons on the planet.

It's a space port in southern california

Where they test launch I.C.B.M.S to make sure

That these intercontinental Ballistic missiles will work

If we need to launch a nuke

Anywhere on the planet in 30 minutes.

[ beeps ]

Narrator: investigators back time

The explosion in the skies to Events logged at vandenberg.

Their findings are heart-stopping.

♪♪

That night, a minuteman iii missile

Was fired from vandenberg air force base.

Narrator: the minuteman Iii is a doomsday weapon.

[ flames whooshing ]

Each missile can carry three Thermonuclear warheads.

[ flames whooshing ]

It was an intercontinental Ballistic missile

That had been launched 4 minutes earlier.

That's terrifying.

♪♪

[ electronic beeps and whirs ]

Narrator: coming up, a strange explosion

Shatters a quiet lunchtime drink.

He's spooked by this glass

Just spontaneously Breaking right in front of him.

Narrator: and the explosive truth

Behind the hawaiian halo.

There's actually things in this World that are truly terrifying

That we don't think of enough.

[ explosion ]

[ static ]

Narrator: researchers link video

Of a huge halo expanding through space

To the launch of a Minuteman iii nuclear missile.

Traveling around seven times The speed of a rifle bullet,

The minuteman enters space On the way to its target.

You're talking about an I.C.B.M. That's been launched into space.

So is there something that's happened?

Did it explode?

Have we nuked space?

[ explosion ]

Narrator: planetary Scientist, sian proctor,

Wants to work out exactly what's going on.

She realizes vital clues Could lie with a key stage

Of the missile's flight. When you get to space,

You actually want to slow that rocket down.

It's traveling at 17,500 miles per hour

And to slow it down and redirect it,

They have to jettison all The fuel that's remaining.

Narrator: proctor believes Highly volatile rocket fuel

Could be linked to the strange phenomenon.

Using a vacuum chamber,

She attempts to recreate Conditions at the point

When the missile ditches its fuel.

I'm going to suck all the air out of it

So there's no air left, just like in space.

Then, we're going to add our fuel.

This fuel represents the fuel that's being

Jettisoned from the rocket.

Okay, I'm going to dump The fuel into our vacuum.

♪♪

Narrator: the liquid fuel vaporizes.

♪♪

Slowed down over a thousand times,

The transition is instantaneous.

That is exactly what happens In space with the rocket.

The fuel is being vaporized.

It's going from a liquid to a Gas instantaneously in space.

Narrator: in the vacuum chamber,

The trapped vapor Gathers in a confined cloud

But the missile's vapor can Surge evenly through space

To form a growing halo.

There's nothing to confine it.

So it's expanding at all directions

And it's moving with the Momentum of the rocket,

And that's what you see in the video.

[ electronic beeps and whirs ]

Narrator: the vapor trail through space

Caught on camera by chance

Is evidence nuclear-capable missiles

Stealthily cross our night skies.

There's actually things in this World that are truly terrifying

And we don't think of enough.

That's what we should be worried about.

[ explosion ]

[ electronic beeps and whirs ]

Narrator: now...

An old british pub is the scene Of a shattering disturbance...

There's something unseen going on here.

The energy is so strong that The glass is turned almost to dust.

Narrator: ...An event that Science cannot fully explain.

Can glass spontaneously shatter?

It's a chain reaction throughout The entire strong glass.

There's no explanation whatsoever.

It's there on camera.

♪♪

Narrator: knowsley, on The outside of liverpool

In the north of england.

This historic village dates Back over a thousand years.

♪♪

An old, local pub, the derby arms,

Gets its name from Ancient lords of the manor.

I've worked here for 5 years, And I really like the place.

It's got a good staff, Good, friendly village,

Friendly customers.

[ electronic beeps and whirs ]

Narrator: but staff believe That among the regulars

Lurks an unseen presence.

♪♪

There's been footsteps on the stairs...

[ footsteps approach ]

Chairs being moved.

♪♪

An old bar member... She saw a man,

Thought it was a customer.

She went to serve him, and he disappeared.

♪♪

I think it is definitely haunted

Because you know someone's there.

You know you're being watched.

Narrator: march 1, 2017... It's A quiet weekday lunchtime

With a handful of customers at the bar.

Normal day, people coming in,

Chilling out, having a few drinks.

♪♪

Narrator: in the corner, One customer is texting

While his pint of beer Settles in the glass.

The gentleman who sat there, Relaxing, having a quiet drink.

Narrator: no one anticipates What happens next.

♪♪

Something makes the pint glass explode.

I've never seen a pint Explode on its own before.

The guy is completely shocked.

He's spooked by this glass

Just spontaneously Breaking right in front of him.

Narrator: this isn't just another rumor

Of ghostly activity.

This time, it's caught on camera.

♪♪

[ clock ticking ]

Pub staff believe it's proof...

Of the paranormal.

A glass definitely doesn't Just explode on its own.

Makes my belief even firmer That there's something here.

Narrator: there are no clear signs

Of a physical explanation.

This spontaneously exploding pint

Has all of the hallmarks of a poltergeist.

Narrator: researchers investigate

The potential cause of the explosion.

[ electronic beeps and whirs ]

What causes fracture Generally is when you have

A force on a material, right?

So you hit it with a hammer.

You're causing a force to Be exerted, and it fractures.

In this particular case, There was, obviously,

No external force applied to the glass.

Narrator: the drinker is texting.

Investigators confirm Nothing from his cellphone

Could trigger the explosion.

But something strange is happening.

Perhaps, we need to look at The material, the glass itself,

For answers.

Narrator: coming up,

An unnatural aerial surge

Threatens an american city...

It was literally a wall of Waves coming up the valley.

♪♪

Narrator: and unlocking the Explosive potential of glass.

There's a huge amount of stress and strain

Built up inside the bulb.

♪♪

[ static ]

♪♪

Narrator: the spontaneously Exploding pint glass

Seems to defy the laws of physics.

Investigators search for an explanation

In the strange nature of glass.

Glassworker nicola Steel knows more than most

About this everyday, Extraordinary material.

When making a piece of glass, We're constantly moving it

Between solid and liquid state.

We're constantly moving the molecules.

So they reform structures,

But it's never a very Even, regulated structure.

Narrator: scientists question whether

The explosion could be triggered

By a property of finished glass That makes it highly dangerous.

Its violent reaction to a Sudden change in temperature.

We probable had some Major temperature changes

In the glass, which can Cause internal forces to exist

Inside the glass itself,

Which can also cause the Glass to crack or fracture.

[ static ]

Narrator: physicists call this Phenomenon thermal shock.

It can create extreme cracking When glasses that are still hot

From the dishwater meet Freshly poured, ice cold beer.

Putting cold liquid inside a hot glass

Is causing two different temperature points

On the same piece of glass.

So your inside is getting Suddenly very chilled,

Where as the outside is still quite warm.

The cold side has contracted Relative to the hot side,

Which has slightly expanded.

The contraction and the expansion can cause

Internal forces, which can Cause the glass to shatter.

Narrator: this thermal shock Phenomenon is all too familiar

To the staff of the derby arms,

Especially when an event Like a popular soccer match

Fills the pub.

♪♪

I've used a hot glass before on match day

'cause there were no Glasses left on match day.

It just shattered in me hand, Just flew up everywhere in bits.

Narrator: thermal shock could Seem like an explanation,

But according to bar staff...

The effect is always instant.

I mean, if it was our hot glass,

It would just explode straightaway

As soon as you put the beer it in.

But it sat there for a good few minutes.

[ electronic beeps and whirs ]

Narrator: glass worker nicola steel

Believes other strange qualities of glass

May create the right Conditions for an exploding pint.

Any other material, I would Be happy to start thinking,

"It is a ghost." but as it's glass,

There's probably a very good explanation.

Narrator: nicola knows a Way to turn ordinary glass

Into a primed bomb, ready to explode.

♪♪

One way we can show the stress

That's contained in a piece of glass

Is by making a thing called A prince rupert drop,

Which is taking a fresh gather Of glass out of the furnace

And dropping it immediately Into a bucket of water.

[ electronic whirs ]

[ rattling ]

It cools it down so quickly,

We're talking under 60 seconds it's dropped

From 1,000 degrees to handling temperature.

Narrator: the bulb of the Glass head hit the water first

And the outside of the bulb solidifies.

The inside of that bulb Has not yet solidified.

It's molten glass, and it Solidifies more slowly.

What happens is, as it solidifies,

It shrinks and it pulls on

The external solidified bulb of the glass.

There's a huge amount of Stress and strain built up

Inside the bulb of the prince rupert drop.

Narrator: nicola's creation Is an explosive device

With a built-in trigger.

That piece of glass is as strong as a rock.

You can hit it. You can stand on it.

You can do whatever you want.

The only way I'm going to Break this piece of glass

Is by breaking the thin tail at the end,

Which is going to cause A flaw in the glass,

Which will release the pressure.

[ glass shattering ]

It causes all that energy to be released,

And that's what causes

The, basically, the Explosion of the glass itself.

♪♪

The energy is so strong that The glass is turned almost to dust.

It's like, almost powder.

Narrator: nicola believes a Factory production error

Speed cooling a pint glass by mistake

Could produce the same outcome.

Nicola: tiny weak points can then

Leave it completely vulnerable to breaking.

Narrator: the result is a ticking time bomb

Of locked-in energy, waiting for detonation

By a small, sudden impact on a weak point.

Tiny cracks sort of Perpetuate through the glass,

And as it's sitting there With a full glass of beer,

Those cracks probably perpetuated

Throughout the glass, shattering the glass.

Narrator: but experts find no evidence

Of any kind of impact on this glass.

It's very weird and hard to Explain what exactly happened.

The fact that clearly nothing heat-wise

Or has hit it or anything like That leaves me really wondering.

Narrator: the definitive Cause of the exploding pint

Remains a mystery.

It is fair to say there's An unseen force operating

At the derby arms.

♪♪

[ electronic beeps and whirs ]

And now... In the deep south,

An apocalyptic vision Appears on the horizon.

What I saw that day in December, it was unbelievable.

Narrator: a series of airborne Tsunami surge towards the city.

This is a warning of some kind.

It was just wave after wave after wave.

♪♪

Narrator: december 21, 2011,

A typical winter day In birmingham, alabama.

Teresa douglas is working in her office.

What she sees from her window On the 19th floor is terrifying.

[ thunder rumbles ]

♪♪

I remember looking out The window and thinking,

"Something wicked this way comes."

Narrator: towering columns of darkness

Advance relentlessly toward her workplace.

They look like huge waves crashing.

Long rolls that just formed out of nowhere.

It didn't stop.

You could look down the Valley and see more waves coming.

Narrator: teresa and her colleagues

Can't believe their eyes.

A coworker turns on his cellphone camera

To confirm this is no illusion.

One of the attorneys came In, and he started filming it.

Narrator: extreme weather can unleash

The full, destructive force of nature.

This seems like some New freakish wave storm.

♪♪

Oh, my gosh.

Where did this come from?

Somebody said it's from god.

♪♪

[ static ]

Narrator: birmingham, alabama...

Some citizens fear the wrath of god

Is sending an apocalyptic Storm to strike their city...

♪♪

And they are no strangers To extreme weather.

Alabama is in the dixie alley,

The nation's highest risk tornado corridor.

[ electronic beeps and whirs ]

I'm hypersensitive to The weather in alabama

Because of tornadoes.

Tornadoes are probably One of the, if not the most

Destructive storms On the face of the earth.

[ thunderclap ]

Narrator: just months before The strange clouds appear,

A deadly meteorological assault strikes.

At the height of the 2011 super outbreak,

12 powerful tornadoes ripped Through the southern state,

Claiming over 200 lives in alabama.

Is this a tornado? Is that what's forming?

Narrator: one of the telltale signs

That a tornado is coming

Is the formation of a funnel cloud.

A funnel cloud is a rotating column of air

That descends from within the thunderstorm.

Once that rotating air reaches the ground,

Then it becomes a tornado.

[ thunderclaps ]

All that energy in that rotating Air is really concentrated

And literally buildings Just come apart dramatically

As they face the onslaught Of tornadic force winds.

[ explosion ]

[ wind howling ]

Narrator: nobody knows the Potential for destruction

Within the looming birmingham clouds.

They look like a line Of freakishly deformed

Super tornadoes... With Funnel clouds at the base,

Yet cresting at the top like ocean waves.

It was literally a wall of Waves coming up the valley.

Funnel clouds typically mean a tornado.

What could wave clouds mean?

♪♪

[ electronic beeps and whirs ]

Narrator: one scientist believes Extreme atmospheric conditions

Could be behind the birmingham cloud event.

After studying the video Of the weird formations

Threatening the city,

Simon foster from imperial college london

Sets up a scaled-down Version of the effect,

Using colored water in place of air.

What we've got here is a tank of Water separated by this divider,

And on the right-hand side,

We've got a body of hot water colored red,

And on the left-hand side,

We've got a body of Cold water colored blue,

And this is going to behave just Like gases in the atmosphere do.

Narrator: if simon's right, When the two waters interact,

They should reproduce The waved cloud effect.

♪♪

When I remove this divider,

The bodies of water don't Simply just mix together.

They actually remain separate, The cold water slipping under.

The hot water rises above it.

♪♪

You'll be able to see these instabilities.

You'll be able to see these Curls appearing in the water,

[ electronic beeps and whirs ]

Just as we see in the Footage of the atmosphere.

Narrator: it's the turbulence at the border

Between the hot and cold

That reproduces the distinctive Wave cloud shapes in the tank

And in the atmosphere.

Results in some of the rarest

And most spectacular cloud Formations on our planet.

They're a phenomenon called Kelvin-helmholtz wave clouds.

The air at the bottom moves More slowly than the air at the top,

And therefore, the wind at the top

Is actually dragging the cloud with it

And pulling it around

In that very strange Kind of wavelike shape,

That billowing curved shape.

Narrator: yet there's something Scientists still can't explain.

These birmingham wave clouds

Require air layers with extreme contrast.

They're usually found miles high in the sky

Or on mountain slopes.

This city is on low-lying, level ground.

This one is striking because it's happening

So close to the ground.

We were getting velocity differences

From about 1,000 feet up, and this is rare.

Typically, we see them At a much higher altitude

Than what we saw in birmingham.

Narrator: why these dark clouds Should rear up in birmingham

Remains a mystery,

But from the safe viewpoint Of her office building,

Theresa douglas' fears turn to wonder

As the wave clouds rose and fell.

It was beautiful.

It was unusual.

I was actually in awe.

I really couldn't say very much,

And I knew I never would See anything like that again.

♪♪