In reply to CosmicHobo:
Conditions will be good.
As you perhaps know, Ticino is mostly a winter boulder area. There is rarely any snow (at least in Cresciano, in Chironico which is higher there can be periods with snowcover) and the normal max temperatures in winter usually are in the 0-10 degrees Celsius range. In May/June the daily max will usually be around 20 degrees. Thus, most would consider it as being a bit warm for doing hard problems. But for the normal weekend warrior, I thinks it's still fine, since also most of the boulders are not exposed to the sun. Magic Wood will be nearly perfect at that time of the year. The snow will be gone and temperatures will be nice.
Regarding rain, you can have bad luck at any time of the year in these areas. Or vice versa, there is no period where you can be sure to remain without rainy days. Being flexible with visiting areas in Ticino or on the northern side, you can often beat the rain, though - weather is highly regional in Switzerland.
