At high altitudes (over 4000m), warm air masses will be moving in on Saturday; lower altitudes will however receive cool, polar air. This combination cool air at lower levels, mild air above and both of them humid will bring us heavy cloud and occasional precipitation.
On Sunday, the sun will break through more often. Monday and Tuesday will temporarily bring unstable weather. Under the influence of a new area of high pressure, the weather will be nice and dry from Wednesday.