Trier weather in September

In September, Trier sees average daytime highs of 18°C and overnight lows near 10°C, with 67 mm of rain across 10.4 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 20°C in the first days to 16°C by the end. The sky is clear or mostly clear about 22% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 18 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Trier's 3rd-clearest and 9th-windiest month. For the whole year in context, see Trier's year-round climate.

Daytime high
18°
4th warmest
Overnight low
10°
9th coldest
Rainfall
67 mm
10.4 wet days
Daylight
12 h 24 min
6:17 AM – 6:39 PM
Cloud cover
65%
3rd clearest
Wind
11 km/h
9th windiest
Solar energy
3.2 kWh/m²
Travel score
5.6
out of 10
Air quality
Moderate
PM2.5 11.1 µg/m³ · 2019

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 20°C in the first days to 16°C by the end.

A typical September day in Trier reaches about 18°C in the afternoon and slips back to 10°C overnight — a 8°C spread between the day's warmth and the night's chill. On most days the high lands between 13°C and 24°C. Set against its neighbours, September runs about 4°C cooler than August and about 5°C warmer than October.

10°20°30°151015202530
Avg high (°C)Avg low (°C)
12011
22011
32011
42011
52011
61911
71911
81910
91910
101910
111910
121910
131810
141810
151810
161810
171810
18189
19189
20179
21179
22179
23179
24179
25179
26179
27169
28169
29168
30168

How September really feels in Trier

Once humidity and wind are folded in, September averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

September sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Trier weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°8213.13.78.40.0
Feb / -1°6711.23.99.80.1
Mar / 7012.7211.51.7
Apr13° / 5711.60.413.53.6
May17° / 7312.9015.15.1
Jun20° / 11°72120165.9
Jul23° / 13°7112.3015.76.4
Aug22° / 13°7011.2014.26.5
Sep18° / 10°6710.4012.45.6
Oct13° / 7311.9010.53.4
Nov / 77131.38.81.0
Dec / 9914.44.180.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 15% of September, with mostly cloudy or overcast conditions the remaining 63%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14159
24159
34159
44159
54159
63961
74060
84060
93961
103961
113862
123862
133862
143862
153862
163763
173763
183763
193763
203763
213763
223565
233565
243565
253466
263367
273169
283070
292872
302773

Chance of precipitation in September

Any precipitation

Trier gets around 67 mm of rain over 10.4 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 36% and peaks near 41% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
134
233
334
434
534
634
735
835
936
1036
1136
1236
1336
1435
1535
1635
1735
1835
1935
2035
2135
2235
2336
2436
2537
2638
2739
2840
2940
3041

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the dry band about 83% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
170246
272235
373234
474224
575223
675223
776222
877212
977212
1079201
1179201
1280191
1381181
1482171
1582171
1684160
1785150
1886140
1986140
2087130
2188120
2288120
2389110
2489110
2590100
2690100
2790100
2890100
299190
309190

Wind in September

Winds average 11 km/h in September.

Across September, daily wind ranges from about 11 km/h on the calmest days to 11 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
111calm
211calm
311calm
411calm
511calm
611calm
711calm
811calm
911calm
1011calm
1111calm
1211calm
1311calm
1411calm
1511calm
1611calm
1711calm
1811calm
1911calm
2011calm
2111calm
2211calm
2311calm
2411calm
2511calm
2611calm
2711calm
2811calm
2911calm
3011calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 18 min at the start of September to 11 h 30 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 108 minutes over September. Sunrise moves from 5:54 AM to 6:38 AM, and sunset from 7:12 PM to 6:07 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.35:547:12
213.25:557:10
313.25:577:08
413.15:597:06
513.16:007:04
613.06:027:01
712.96:036:59
812.96:056:57
912.86:066:55
1012.76:086:52
1112.76:096:50
1212.66:116:48
1312.66:126:46
1412.56:146:43
1512.46:156:41
1612.46:176:39
1712.36:186:36
1812.26:206:34
1912.26:216:32
2012.16:236:30
2112.06:246:27
2212.06:266:25
2311.96:286:23
2411.96:296:21
2511.86:316:18
2611.76:326:16
2711.76:346:14
2811.66:356:12
2911.56:376:09
3011.56:386:07

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.2 kWh/m².

For context, solar energy here swings from a low near 0.66 kWh/m² to a high of 5.49 kWh/m² in June across the year — September's 3.2 kWh/m² falls in the middle.

01234151015202530
Solar energy (kWh/m²)Level
13.8Moderate
23.8Moderate
33.7Moderate
43.7Moderate
53.6Moderate
63.6Moderate
73.6Moderate
83.5Moderate
93.5Moderate
103.4Moderate
113.4Moderate
123.4Moderate
133.3Moderate
143.3Moderate
153.2Moderate
163.2Moderate
173.1Moderate
183.1Moderate
193.1Moderate
203.0Moderate
213.0Moderate
222.9Moderate
232.9Moderate
242.8Moderate
252.8Moderate
262.7Moderate
272.6Moderate
282.6Moderate
292.5Moderate
302.5Moderate
Planning a trip in September

Is September a good time to visit Trier?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.6
Sightseeing
4th-best month of the year
1.9
Beach & pool
4th-best month of the year

September is a reasonable time to visit Trier for sightseeing.

What to pack for Trier in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Trier sees daytime highs around 18°C and nights near 10°C. Worth packing: rain gear. About 10 days see rain.

rain gear

UV index in Trier in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 4 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Trier peaks around July 16 at about 7 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 16UV 7Jan 1UV 1
UV index (midday)Level
Jan1Low
Feb1Low
Mar3Moderate
Apr4Moderate
May6High
Jun7High
Jul8Very high
Aug7High
Sep4Moderate
Oct3Moderate
Nov1Low
Dec1Low
Location & terrain

Where is Trier?

Trier sits at 49.8°N, 6.6°E, 141 m above sea level, in Germany. The nearest listed city is Konz, 8.0 km away.

Topography around Trier

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Trier.

Within 3 km, the terrain around Trier has significant variations in elevation — a maximum elevation change of 269 m around an average of 196 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 601 m; within 80 km, large variations in elevation — a maximum elevation change of 747 m.

The land around Trier is covered by trees (55%) and artificial surfaces (29%) within 3 km, trees (55%) and grassland (21%) within 16 km, and trees (52%) and grassland (24%) within 80 km.

3 km
269 m
16 km
601 m
80 km
747 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Konz 8.0 km · Losheim 28 km · Wadern 30 km · Wittlich 31 km · Merzig 35 km · Schmelz 39 km · Beckingen 40 km · Luxembourg 40 km

Germany travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / F
230 V · 50 Hz
Prices
≈ 80% of US
price level, 2025
GDP per capita
$60,496
2025
Happiness
6.9 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
0.9
per 100k, 2023
Road deaths
3.8
per 100k/yr, 2019
Income group
High
World Bank
English
Very high
EF EPI 615
Religion
none 44%Roman Catholic 25%Protestant 23%other 5%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Trier (49.7557°, 6.6394°, elevation 141 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).