"In-season" in Luxembourg, as in the rest of the Benelux countries, means from about mid-April to mid-October. The peak of the tourist season is in July and August, when the weather is at its finest. The weather is never really extreme at any time of year, and if you favor shoulder- or off-season travel, you'll find the Grand Duchy every bit as attractive during those months. Not only are hotels and restaurants cheaper, less crowded, and more relaxed during this time, but some very appealing events are going on. Theater is most active during winter months in Luxembourg City.
Climate -- Luxembourg has a moderate climate, with less annual rainfall than either Belgium or the Netherlands, since North Sea winds have usually wept their tears before they get this far inland. The vineyard-rich Moselle Valley in the southeast has the lowest rainfall, with between 30 and 41 centimeters (12-16 in.), and the western districts have the highest, with around 100 centimeters (40 in.). July and August temperatures in Luxembourg City average 63°F (17°C). Winter temperatures average 32°F (0°C). Snowfalls, which open up the cross-country and downhill skiing pistes in the Ardennes, are common but not guaranteed.
Holidays -- National holidays in Luxembourg are New Year's Day (Jan 1), Shrove Monday (the Mon before Ash Wednesday), Easter Monday, Labor Day (May 1), Ascension Day (40 days after Easter), Pentecost Monday (Mon following the seventh Sun after Easter), Luxembourg National Holiday and the Grand Duke's official birthday (June 23), Assumption (Aug 15), All Saints' Day (Nov 1), and Christmas (Dec 25 and 26).
