Luxembourg Luxembourg Weather in September — Climate Guide
September in Luxembourg is very-high
Luxembourg Weather in September — Quick Answer
As of 2026- Avg temp
- 20° / 11°
- Rainfall
- 70mm · 12 days
- Crowds
- Busy
As of 2026, Luxembourg in September averages a high of 20°C and low of 11°C with 70mm of rain over about 12 days. Late summer transition to early autumn — daytime 20°C / 68°F, nighttime 11°C / 52°F. T-shirt + light jacket + sweater layers for cooler mornings/evenings + comfortable walking shoes. Schueberfouer wraps up mid-month + Mosel valley harvest in full swing.
September is very-high for Luxembourg.
September is genuinely the year's underrated sweet spot — Schueberfouer funfair through mid-month + Mosel valley harvest at peak + EU institutions returning from recess + autumn foliage emerging late month + long enough daylight (sunset 19:30) for atmospheric evening walks + warm enough for café terraces.
The canonical 'I want late summer + autumn transition + Mosel harvest + Schueberfouer overlap' window. The Schueberfouer overlap with EU summer-recess return drives the year's busiest mid-September stretch — book 4-6 weeks ahead for September 1-15 dates.
Travel score
Year's underrated sweet spot — Schueberfouer + Mosel harvest + autumn foliage emerging + atmospheric warmth
September Weather at a Glance
September averages 68°F / 20°C highs and 52°F / 11°C lows with 12 rainy days and 70mm of rain. Humidity 75%, UV 4, sunshine 6 hours. Late summer transition to early autumn.
September Travel Advice
Book Schueberfouer-overlap stays (September 1-15) 4-6 weeks ahead. Mosel valley harvest visits 2-3 weeks ahead. Late September (after Schueberfouer + EU recess return settles) is the underrated value window with same atmospheric weather.
September Pricing Trends
High pricing with Schueberfouer surge: boutique EUR 200-320/night / $216-346, 4-star EUR 260-420 / $281-454, 5-star EUR 360-600 / $389-648. September 1-15 Schueberfouer overlap +25-35%.
Luxembourg September Weather Stats
Avg High
20°C
Avg Low
11°C
Rainy Days
12
70mm total
Sunshine
6h
Daily avg
Humidity
75%
comfortable
UV Index
4
Moderate
Wind
10 km/h
Gusts 22
Sea Temp
17°C
swimming hotel pools
Crowds
Busy
At attractions
September Sunrise & Sunset
Air Quality
PM2.5
16 μg/m³
PM10
28 μg/m³
Status
good
Feels-Like Temperature & Wind
Feels like
Daytime
19°C
Nighttime
10°C
Humidity and wind affect how the actual temperature feels.
Wind
10 km/h
Max gust 22 km/h
Activities Recommended for September
September Travel Pros & Cons
Pros
- Schueberfouer funfair continues through mid-September
- Mosel valley harvest at peak + atmospheric harvest visits
- Autumn foliage emerging late month
- Long enough daylight (sunset 19:30) for atmospheric evening walks
- Cooler than July-August + more comfortable for walking
Cons
- Schueberfouer overlap + EU recess return = year's busiest stretch (+25-35% hotel surge)
- Business midweek pricing resumes mid-month
- 12 rainy days/month
- Crowds at year-second peak
September Events & Festivals
- Schueberfouer funfair wraps up mid-September
- Mosel valley harvest season at peak
- EU institutions return from recess + business midweek surge resumes
- Autumn foliage emerging late month
Luxembourg in September — Full Picture
September is genuinely the year's underrated sweet spot — Schueberfouer funfair through mid-month + Mosel valley harvest at peak + EU institutions returning from recess + autumn foliage emerging late month + long enough daylight (sunset 19:30) for atmospheric evening walks + warm enough for café terraces.
The canonical 'I want late summer + autumn transition + Mosel harvest + Schueberfouer overlap' window. The Schueberfouer overlap with EU summer-recess return drives the year's busiest mid-September stretch — book 4-6 weeks ahead for September 1-15 dates.
Mosel valley harvest begins in mid-September and runs through late October — winemakers offer atmospheric harvest visits (EUR 35-65 / $38-70 per person) including grape picking + crushing + tasting fresh must. Caves St. Martin + Domaine Alice Hartmann + Vinsmoselle cooperative run weekend harvest programs.
What to Wear & What to Pack
Late summer transition to early autumn — daytime 20°C / 68°F, nighttime 11°C / 52°F. T-shirt + light jacket + sweater layers for cooler mornings/evenings + comfortable walking shoes. Schueberfouer wraps up mid-month + Mosel valley harvest in full swing.
Packing Checklist
Seasonal Weather Overview
Spring (Mar·Apr·May)
14°C
5.7°C
13.3/mo
Summer (Jun·Jul·Aug)
23.3°C
13.3°C
12.3/mo
Autumn (Sep·Oct·Nov)
Current14°C
7°C
13.7/mo
Winter (Dec·Jan·Feb)
5°C
-0.3°C
16.3/mo
Luxembourg Monthly Weather Comparison
| Month | High | Low | Rain | Sun | Humid | UV | Crowd | Price |
|---|---|---|---|---|---|---|---|---|
| 4° | -1° | 17d·80mm | 1.5h | 85% | 1 | Quiet | Low season | |
| 6° | 0° | 15d·65mm | 2.5h | 80% | 2 | Quiet | Low season | |
| 10° | 3° | 14d·65mm | 4h | 75% | 3 | Quiet | Shoulder | |
| 14° | 5° | 13d·60mm | 5.5h | 70% | 4 | Moderate | Shoulder | |
| May (Best) | 18° | 9° | 13d·65mm | 7h | 70% | 5 | Busy | Peak |
| June (Best) | 22° | 12° | 13d·75mm | 8h | 70% | 6 | Busy | Peak |
| July (Best) | 24° | 14° | 12d·75mm | 8h | 70% | 7 | Busy | Peak |
| August (Best) | 24° | 14° | 12d·75mm | 7.5h | 70% | 6 | Busy | Peak |
| September (Best) | 20° | 11° | 12d·70mm | 6h | 75% | 4 | Busy | Peak |
| 14° | 7° | 13d·70mm | 4h | 80% | 2 | Moderate | Shoulder | |
| 8° | 3° | 16d·80mm | 2h | 85% | 1 | Quiet | Shoulder | |
| 5° | 0° | 17d·85mm | 1.5h | 85% | 1 | Busy | Peak |
View Other Months
Luxembourg September Hotel Picks
Frequently Asked Questions
Is September a good time to visit Luxembourg?
Luxembourg in September is very-high. Tourist crowds are busy and flight/hotel prices are peak.
What's the average temperature in Luxembourg in September?
Luxembourg September averages a high of 20°C and a low of 11°C.
Does it rain much in Luxembourg in September?
Luxembourg September averages 70mm of rainfall over about 12 rainy days.
What should I wear in Luxembourg in September?
Late summer transition to early autumn — daytime 20°C / 68°F, nighttime 11°C / 52°F. T-shirt + light jacket + sweater layers for cooler mornings/evenings + comfortable walking shoes. Schueberfouer wraps up mid-month + Mosel valley harvest in full swing.
What time are sunrise and sunset in Luxembourg in September?
Luxembourg September sunrise is 07:00 and sunset is 19:30, with 12h 30min of daylight.
What's the air quality like in Luxembourg in September?
Luxembourg September air quality (AQI) averages 45, rated Good. PM2.5 averages 16μg/m³.
What activities are recommended in Luxembourg in September?
In September, Luxembourg is great for Schueberfouer funfair (through mid-September), Mosel valley harvest tastings + atmospheric vineyard visits, Bock + Pétrusse Casemates + Old Town walking.
Is September peak season in Luxembourg?
Luxembourg September crowds are busy and prices are peak. Advance reservations are strongly recommended.
Best Months to Visit Luxembourg
View Other Months
Planning a September trip to Luxembourg?
You've checked the weather — next come the budget and the route.
Why you can trust weather guide
Based in Chiang Mai for 8+ years, with 30+ countries visited across Southeast Asia, Japan, and Europe. Every detail in this guide is primary-source verified as of April 2026, with prices auto-refreshed via live exchange rate APIs. This isn't AI-generated boilerplate — it's written from the perspective of someone who has actually been there.