Version Française.

Photographs of Storms.

Introduction.

The clouds of storms are called of cumulonimbus.
They appear when there is:

A strong gradient of temperature in the air close to the soil.
Enough humidity in air.
A temperature raised on the soil. It is not obligatory, but this really allows to speed up this mechanism.

An interesting animation: full evolution of the cumulonimbus.
I had the chance to take some picture of an equivalent situation of this animation. This is a cumulus which attained the tropopause while remaining small. Here is result:

Photo It is a cumulus which developed on the side of a mountain. I arrive a bit late, we are there already on cumulus congestus stage.	Photo It puts on weight, he puts on weight enough to achieve tropopause . Strangely he remains small, what makes easier the photograph.	Photo The anvil begins then has form. Perhaps it falls some drops?
Photo Then the anvil expand and inhales the bottom of clouds.	Photo The anvil expands, the foundation of the cloud has disappears.	Photo Then it remains finally only the anvil, namely clouds at high altitude.

Cumulus

At first, a cumulus which burgeon.
If there is enough energy, it increase on weight. The summit takes altitude, its surface increase.

Photo

Everything begins by some cumulus which forms in morning.
But I have take this photograph in the evening...

Photo

Here is some cumulus in the morning in Tanzania, in Serengueti (beginning of January). We find the same in europa.

Photo

Slightly later in the morning, cumulus magnify a bit.

Photo

Some cumulus another morning...

Cumulus Congestus.

Then if there is enough energy, small cumulus become cumulus congestus...

Photo

A cumulus rise above Alps.

Photo

Slightly later it becomes more menacing.

Photo

An cumulus already big in the crater of Ngorongoro.

Photo

Begin of afternoon in Serengueti (begin of january).

Cumulonimbus calvus: begin of life...

The cumulus congestus become a cumulo-nimbus calvus when it start raining.

Photo A cumulus congestus that is close to a cumulo-nimbus.	Photo At first the cumulonimbus is of type " Calvus ", because the head is rounded up.	Photo This photograph, precedents and the following are catch in Tanzania. In the middle of the day in January in lowland, they have already rise a lot.	Photo This one is big and is in Tanzania. View its size, it will soon create its anvil...
Photo Another cumulo-nimbus.	Photo	Photo	Photo

Other internet picture : Cumulo nimbus Calvus.

Cumulonimbus capillatus: the torrential rain.

When there is enough energy in summer, the summit of the cloud attains the tropopause (±12km in France). The tropopause is altitude at which the temperature of air stops decreasinging with altitude to warm itself up again.
It stop the upward movements of air, the cumulonimbus calvus becomes cumulonimbus capillatus by forming an anvil. In general the torrential rain starts now, or a bit before.
The anvil begins gently, sometimes by a bulge of the summit, then its size augments according to the quantity of rising air which feeds it.

Photo A storm is in French jura. The city Chaud-de-Fond (Swiss jura) is under the huge anvil.	Photo The same cumulonimbus 2h later. The storm loose power and the anvil reach the maximum development.	Photo A far storm start to builéd its anvil.	Photo Here is a storm sliding towards the northeast along the slopes of jura. The high altitude clouds conceals a bit the general aspect, but we can see the storm enough.
Photo On the side, the cumulonimbus shows a broadly formed anvil.	Photo Probably a torrential rain which begins on the Alps.	Photo A pretty anvil in Tanzania.	Photo idem
Photo idem	Photo idem	Photo idem	Photo idem
Photo	Photo	Photo

Under the torrential rain...

The arrival of the torrential rain is made of a different manner. Sometimes with a cumulonimbus with an anvil not much formed, sometimes under a huge anvil!

Photo Here a strong torrential rain bursts above jura. We are under a cumuluo-nimbus.	Photo An arrival of a strong torrential rain another day. I have had the chance to think me in good place at good instant.	Photo (1600*1200) 5 minutes later the arrival of the rain on the lake of Bienne appears like a curtain that fall from the sky.	Photo The edge of a storm.
Photo The edge of a storm.	Photo The same storm view under an angle more on left.	Photo A photograph which I think interesting. Sometimes a clouds take this form at the end of torrential rain.	Photo The big anvil introduces in beginning of evening is a bit dispelled. This gives at the storm above the lake of Bienne more colour.
Photo Same picture take horizontally.	Photo Storm in Tanzania.	Photo Storm in Tanzania.	Photo

After the torrential rain...

The anvil seems to have tendency to inhale the foundation of the cloud. If there is no more hot air to feed the cumulonimbus, then the foundation of the cloud goes back up in altitude. The intensity of rains diminish progressively.

Photo

The end of the torrential rain is not very clear here. The cumulonimbus is accompanied with other cumulus which cover the sky.

Photo

A group of storms has already formed a nice anvil.
A younger cumulonimbus in the middle is still actively acting.

Photo

On the soil, patches of fog form in certain valley in shelters of the wind.

Photo

Sometimes after the storm, we see an anvil behind it that is already well formed.

Died of a Cumulonimbus.

Movement represented before goes on until there does not remain more than the anvil, then more than clouds has high altitude as cirri and cirrostratus.

Photo The end of life goes by the deployment of high alitude cloud (altostratus, altocumulus, cirrocumulus)	Photo The end of a cumulonimbus give sometimes big panache. When they are isolated, they give this form...	Photo When a good part of the anvil or the panache could restless, it often remain some cirrocumuli in the evening.	Photo But there can also remain benches darker of altostratus.
Photo A storm which burst in the west of jura end its life in French-speaking Swiss. It is a classical phenomenon in the region. It does not remain more than the anvil at this cloud... in course of clearing up.	Photo It is the end of pretty cumulonimbus in Tanzania. 2 h at 3 h after his blasting, it was completely transferred in high altitude.	Photo After a sunset, it is that it remains of a cumulonimbus.

Stormy Zone.

Sometime a Cumulonimbus are not alone and other cumulus and cumulus-congestus at different evolution stadiums. Because of the important air movements generated, the sky is also filled with altocumulus, with altostratus, with cirrocumulus that gives a covered weather.

Photo One day, different cumulus congestus, which formed on the Alps and jura, being transformed into cumulonimbus, and their anvil merged. The sky is completely covered, and some showers burst a bit everywhere.	Photo When every cumulonimbus finished them fusion, the form of clouds becomes less net.	Photo One day when a cumulus, cumulonimbus, and anvil blends, gets tangled and gives a covered sky.	Photo Same remark.
Photo Same remark.	Photo

Interesting Sites.

Sites according to bring photographs and explanation on stormy phenomena.
As it is already very well made, I content myself with putting links:

Thunderstorms and Tornadoes.
Weather_front, Wikipedia.
Thunderstorm, Wikipedia.
Supercell, Wikipedia.
Thunderstorm chaser.com
Night Lightning.
Severe Thunderstorms in Australia.
Metoffice.gov.uk, thunderstorms.
Thunderstorms and Tornadoes.
pilotplanning.com: some pictures are about thunderstorms!
physical geography : Thunderstorms and Tornadoes
Supercell, Wikipedia.
A word document about thunderstrom , coming from "calmet.comet.ucar.edu", 286Ko.
A powerpoint document "understanding the weather" , coming from "www.eas.slu.edu", 3.09Mo.
Observing thunderstorms.
Texas Mother Ship Cloud.

Photo from satellite:

Photo

( 1600*1200 )

photograph of storm - photograph of cumulonimbus - storm in Swiss - photograph of cumulus - photograph of torrential rain - photograph of wall of rain

Created the : 18 july 2004.
Last update: 22 may 2008.

Moostik

View My Stats