UKC

On one hand, with more snow falling rocks would be slowed. On the other hand, with more snow there is more movement of rocks as the snow melts. And thus ends the extent of my ability to infer my answer from my own theorization.

Anyone with REAL expertise able to provide an answer?

Thanks!

In reply to owenel:
Look listen then move fast, its known as the bowling ally .
Take care what ever time of year it is .

In reply to owenel:

June

In reply to owenel:

I'm no expert, but I'd definitely say June. Superficial snow cover probably plays less part in the coherence of the shattered rock on the face than sub-surface ice - reports suggest that shrinkage of ancient permafrost as temperatures rise is a key factor in recent increases in rockfall in the Alps. So as the season goes on, freeze-thaw and then melting of the winter's ground ice that helps hold the substrate of choss together, combined with the release of lubricating groundwater, probably makes for a progressive increase in instability. Ever more so now that even above 3000m, night temperatures often aren't falling below freezing in July and August. Night frosts may return in September, but it'll take sustained low temperatures to re-freeze the substrate.

In reply to owenel:

Varies every year, in recent years most likely in June. Currently it is 'closed' as this has been a very dry year ( the driest I can remember for many years) so natural rockfall is abundant. A proportion of the rockfall on the route is caused by others higher on the route - whilst anyone can accidentally knock rocks off the high proportion of novices on this route seems to exacerbate the problem. So if the freezing level is fairly low and you go at a time of day when fewer people are on the route you can sway the odds somewhat.
As with any route in the alps, check for local up to date information in the local guides office as conditions of routes can change dramatically in a very short space of time.
We were on the Peigne a few days ago when two rockfalls swept down our intended route and the whole Aiguille felt like it vibrated. We chose to do a different route nearby. Some groups arriving later chose to carry on !?!