GALLERY Lenticular Cloud Display Along Ireland's East Coast, 6 September 2012

Lenticular clouds, which are sometimes referred to as 'pancake clouds', 'lennies', 'wave clouds' or 'UFO clouds', are characteristic of all mountain ranges and form in response to wind. We have compiled a collection of Lenticular cloud images, captured across Ireland's east coast on the evening of Thursday, 06 September 2012.

Click on images to enlarge.

Arklow, Wicklow. Image Niamh Clandillon Mills
Lenticular clouds as seen from Inchicore last evening. Image Alan Coholan
Altocumulus lenticularis, Finglas, Dublin. Image Ian Carruthers

County Meath. Image Seamus Crowley
Dublin 11. Image Jenny Ryan
Hollyford, Co Wexford. Image Jackie Mischler Woods
Kilcock, Kildare. Image Moira Vorster
Lenticular Clouds over the Dublin Mountains. Image John Murphy
Wicklow. Image Mary Redmond
Wave Winds. Image Wikimedi
Lenticular clouds explanation: When strong winds blow over the mountains and force moist air up to cooler elevations, the moisture condenses. As the winds blow back down the other side of the mountains, the moisture re-vaporizes. The lenticular cloud is the condensed (visible) moisture under the wind stream; it doesn't drift like other clouds do because it's "trapped" in a pocket of relatively calm air just below the wind stream and just above warmer air below. The notion that the clouds are stationary is an optical effect. A lenticular cloud actually is forming on one end (front edge) and vanishing on the other, giving the appearance that it is in a fixed position. Lenticular clouds assume distinct shapes, generally resembling a disc (hence giving rise to a common name of "pancake clouds" or in a flat elongated shape stretching parallel to the mountain range.