Undercasts and their non-uniformities

[csearle]

Just arrived in Luxembourg from City. Flew mostly between two cloud layers. Couldn't help wondering how/why the undercast sported quite a few fissures through which I sometimes fancied the ground could be seen.

Does anyone know what might explain these? The terrain below maybe? Or, maybe other cloud-busting aircraft? Both seem unlikely to me.

Thanks,
Chris

[tjh290633]

Probably two decaying fronts, with three air masses involved. Maybe an old warm sector below, then a cold sector then another warm sector above with its own warm front giving rise to the upper cloud.

You would need to have a look at the synoptic chart for the day involved.

TJH

[csearle]

Thanks Terry. Should have taken a photo. These things looked like the cloud was made of earthenware that had been glued together after shattering into, say, five pieces. C.

[tjh290633]

Thanks Terry. Should have taken a photo. These things looked like the cloud was made of earthenware that had been glued together after shattering into, say, five pieces. C.

Might have been a mackerel sky, altocumulus, if that was the upper layer.

TJH

[csearle]

Well I saw these cracks below me whilst flying at FL23. I think they were through the stratus down to ground.

If I see them on the way back (unlikely) I'll take a picture. C.

[tjh290633]

Well I saw these cracks below me whilst flying at FL23. I think they were through the stratus down to ground.

If I see them on the way back (unlikely) I'll take a picture. C.

If you were at FL23, then my vote would be for altocumulus as the lower level.

TJH

[csearle]

No chance of a photo. Turns out that it's dark at 2130 CET.