The deep valleys of the Alps are great places to learn mountain meteorology. The have somewhat regular thermally forced valley and slope flows when the large-scale flow is weak and fascinating terrain-forced flows when the large-scale flow is strong. Clouds are frequently present and are useful for understanding local flow patterns.
Saturday night bought valley rain and mountain snow to western Austria. Sunday morning I went for a hike above our apartment to a mountain hut. On the return, I noticed shallow mid-slope cumulus clouds on the south side of the valley, beneath a more layered stratiform cloud that was hovering at higher elevations close to ridgeline.
The local time was about 1200 so I suspect that surface heating was leading to upslope flow that generated those shallow clouds. In the wake of the storm, the airmass over the valley was relatively moist and reached saturation with a little ascent to generate the clouds. Given their shallow nature, the cumulus clouds suggest that the low-level upslope flow was not penetrating all the way to the ridgeline, but was confined to the lower valley atmosphere.
That's the hypothesis anyway, although it's hard to evaluate with observed data in this case.
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