Luxembourg's weather and climate, month by month

Luxembourg’s climate won’t frighten anyone, but it won’t let you forget about it either. Winters are cold and grey, summers are gentle, and the rain never quite goes away. Here’s what the country’s own weather service says month by month, and how I’d use it when planning a trip.

What MeteoLux actually measures

MeteoLux works out its averages at Findel, the weather station on the airport plateau just outside the capital, so it’s the climate you step into when you land. For 1991 to 2020 the yearly mean is 9.8°C. The coldest month is January, averaging 1.4°C (35°F), and the warmest is July, at 18.7°C (66°F), with August close behind on 18.4°C. Spring warms up fast, from 5.7°C in March to 13.5°C in May, and autumn drops just as sharply, from 14.3°C in September to 5.2°C in November.

Average highs and lows aren’t in that table. STATEC publishes them for Luxembourg City, but only for four months. January runs from a high of 4.7°C to a low of −1.0°C; April from 15.3°C to 3.5°C; July from 24.9°C to 12.4°C; October from 14.7°C to 5.7°C. It’s a different series from Findel’s, so the averages don’t match exactly. I treat it as a rough guide to what days and nights feel like.

How much does it rain?

The yearly total is 831 mm, and what shapes the climate is how evenly it falls. No month drops below 49 mm. April is the driest on 49.4 mm and December the wettest on 89.5 mm. From May to August the monthly totals barely move, around 72 or 73 mm, but they come in bursts, with 8.6 thunderstorm episodes on average in June and 8.0 in July against less than one a month from November to March.

In practice, there’s no month when I’d leave the waterproof behind. The full kit list, season by season, is in what to pack for Luxembourg.

Once your dates are set, check which hotels are still free in Luxembourg before prices climb.

Sunshine and fog, the real difference between seasons

This is where the seasons part company. Findel logs 1,803 hours of sunshine a year, very unevenly shared. July reaches 257.6 hours while December manages 41.9. From November to January no month tops 52 hours, and fog piles on top, with 10.8 days in November, 11.3 in December and 10.2 in January. By April fog has nearly gone (1.8 days) and sunshine is past 197 hours.

For me that matters more than the thermometer. A December afternoon in the capital is short and often grey, and an Ardennes viewpoint can vanish into cloud. From May to August there’s enough light for a morning walk and a castle in the afternoon. If you’re still choosing dates, I’ve ranked them in the best time to visit Luxembourg.

Ice, heat and the record books

Icy ground turns up on 3.4 days a year on average, almost all of them in December (1.4) and January (1.3). Snow can fall, but MeteoLux doesn’t publish snow days on that page, and the capital’s tourist office is careful about it, saying that with luck there’ll be some. I wouldn’t build a trip on it.

Findel’s extremes since 1947 show the other side. The heat record, 39.0°C (102°F), dates from 25 July 2019, and August hit 37.9°C in 2003. The cold record is −20.2°C, on 2 February 1956. They’re rare days, but a useful reminder that averages aren’t the whole story.

Once your dates are set, check which hotels are still free in Luxembourg before prices climb.

Is Vianden colder than Belval?

A little, though less than most people expect. The government’s guide to the country (SIP, “Everything you need to know about Luxembourg”) puts the variation between north and south at around 2°C and puts it down to altitude. Up top is the Oesling, Luxembourg’s slice of the Ardennes, a third of the territory with the highest point in the country, 560 m at Wilwerdange, and a climate the same booklet calls harsher than elsewhere. Its main towns are Wiltz, Clervaux and Vianden, and the Troisvierges plateau at the very top is the coldest and wettest part of the Grand Duchy.

Below lies the Gutland, two thirds of the country, with the capital at 300 m, the Moselle valley to the east and the old mining basin in the south, home to Esch-sur-Alzette and Belval. Echternach, down in the Sûre valley, is outside the Oesling too. No official source publishes separate averages for Vianden, Echternach or Belval, so I won’t invent figures town by town. My working rule from what does exist is simple enough. If you’re based in the capital and heading up to Clervaux or Vianden, take an extra layer and expect a bit more cold and rain than in town; for Belval and the south, I’d use the Findel table as a fair guide.

How I’d plan around the weather

December to February, the capital, its museums and the Winterlights markets. April to June, the Mullerthal and the north on foot, with long days and none of July’s heat yet. Summer for the lakes, the festivals and the Moselle. Autumn for the wine harvest and turning woods, with fog creeping back from October. Each season has its own page, from Luxembourg in winter to Luxembourg in summer, and each month too, starting with Luxembourg in January.

One practical note if you’re heading north or into the Mullerthal. The averages are Findel’s, and beyond the government’s 2°C between north and south, I won’t give you differences I can’t back up. Check the forecast the evening before, and in summer keep an eye on heat and wildfire warnings, which Visit Luxembourg points to the national LU-Alert system for.

If you would rather have a local show you round, book a guided tour in Luxembourg and choose by the reviews.

A car frees you from timetables: search car hire in Luxembourg on DiscoverCars and compare companies.

So you do not pay over the odds, look at trains, coaches and flights to Luxembourg on Omio and pick the one that suits you.