Lenicular cloud over Mulhacen south ridge
There is no doubt that the formation of spectacular lenticular clouds is a magnificent sight for mountaineers. However their development sends out warning signs for those enjoying the mountain environment. In Spain’s Sierra Nevada they are commonplace, more especially in the winter when they can develop with startling rapidity.
They are a sure sign of very high wind speeds at altitude. They can also signal the onset of bad weather within a 24 to 48 hour period. In Chamonix we always used to head down when we saw these developing over Mont Blanc or the Aiguille Verte. Invariably the bad weather system would follow.
What are Lenticular clouds?
www. wisegeek.com suggests the following………….
They form when a current of moist air is forced upwards as it travels over a mountain, causing the moisture to condense and form a cloud. Sometimes the air is forced into a wave pattern, generating what is known as a wavecloud. Wave clouds can look like strings of discs spreading out from the leeward side of the mountain. They can also form miniature waves which sometimes look exactly like a choppy sea.
One interesting thing about lenticular clouds is that they look like they are perfectly stationary and frozen in time. This is not, in fact, the case. These clouds appear stationary because the flow of moist air continually resupplies the cloud from the windward side even as water evaporates and vanishes from the leeward side. Lenticular clouds can look like they are hovering for hours or days, until the wind or weather changes and the cloud disperses.
Having said all that they are a thing of beauty for the photographer who is able to capture these magnificent phenomenons. Our Outdoor Photography Courses include capturing the skies of the Sierra Nevada.
