Wil weather in September

In September, Wil sees average daytime highs of 18°C and overnight lows near 12°C, with 106 mm of rain across 12.1 wet days and about 12.4 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 20°C in the first days to 17°C by the end. The sky is clear or mostly clear about 27% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 12 min at the start of September to 11 h 30 min by month's end. Set against the rest of the year, September is Wil's 4th-clearest and 9th-windiest month. For the whole year in context, see Wil's year-round climate.

Daytime high
18°
4th warmest
Overnight low
12°
9th coldest
Rainfall
106 mm
12.1 wet days
Daylight
12 h 18 min
6:08 AM – 6:28 PM
Cloud cover
60%
4th clearest
Wind
7 km/h
9th windiest
Solar energy
3.56 kWh/m²
Travel score
5.6
out of 10

Wil is city and municipality in the canton of St. Gallen, Switzerland.

Density
1,151/km²
people per km²

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 17°C by the end.

A typical September day in Wil reaches about 18°C in the afternoon and slips back to 12°C overnight — a 7°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°15°20°25°30°151015202530
Avg high (°C)Avg low (°C)
12113
22113
32013
42013
52013
62013
72013
82013
91912
101912
111912
121912
131912
141912
151912
161812
171811
181811
191811
201811
211811
221811
231711
241711
251711
261710
271710
281710
291610
301610

How September really feels in Wil

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.

Wil weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 5th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -1°8212.56.58.70.0
Feb / -1°7311.36.59.90.2
Mar10° / 8813.94.611.61.9
Apr14° / 9013.21.813.33.6
May18° / 10°13115.60.214.95.0
Jun21° / 14°13215.1015.75.8
Jul23° / 15°12814.8015.46.3
Aug23° / 15°12914014.16.3
Sep18° / 12°10612.1012.45.6
Oct14° / 9111.70.410.63.7
Nov / 9512.33.29.11.2
Dec / 98146.48.30.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 27% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 55%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15050
24951
35050
44951
54951
64852
74852
84852
94852
104753
114753
124753
134753
144654
154654
164456
174456
184456
194456
204357
214357
224258
234258
244159
254159
264060
273961
283862
293862
303763

Chance of precipitation in September

Any precipitation

Wil gets around 106 mm of rain over 12.1 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 41% and peaks near 44% on the wettest days.

0%10%20%30%40%50%151015202530
Rain chance (%)
144
244
344
444
544
643
743
843
942
1042
1141
1241
1341
1440
1540
1640
1739
1839
1939
2039
2139
2239
2339
2439
2539
2639
2740
2841
2941
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 67% of days. It rarely turns muggy — the humid and sticky bands barely register.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)
1493119
2513118
3523117
4543115
5553114
6563113
7573112
8583111
9593110
1060319
1161318
1263307
1363307
1464306
1566295
1666295
1768284
1869274
1970273
2071263
2173252
2274242
2376231
2477221
2578211
2679201
2781190
2882180
2983170
3084160

Wind in September

Winds average 7 km/h in September.

Across September, daily wind ranges from about 6 km/h on the calmest days to 7 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187calm
197calm
207calm
217calm
227calm
237calm
246calm
256calm
266calm
276calm
286calm
296calm
306calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 12 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 102 minutes over September. Sunrise moves from 5:47 AM to 6:28 AM, and sunset from 7:00 PM to 5:59 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.25:477:00
213.15:496:58
313.15:506:56
413.05:526:53
513.05:536:51
612.95:546:49
712.95:566:47
812.85:576:45
912.75:586:43
1012.76:006:41
1112.66:016:39
1212.66:036:37
1312.56:046:35
1412.56:056:32
1512.46:076:30
1612.36:086:28
1712.36:096:26
1812.26:116:24
1912.26:126:22
2012.16:146:20
2112.06:156:18
2212.06:166:15
2311.96:186:13
2411.96:196:11
2511.86:216:09
2611.86:226:07
2711.76:236:05
2811.66:256:03
2911.66:266:01
3011.56:285:59

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 3.56 kWh/m².

For context, solar energy here swings from a low near 1.02 kWh/m² to a high of 5.58 kWh/m² in June across the year — September's 3.56 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.2Bright
24.1Bright
34.1Bright
44.0Bright
54.0Bright
64.0Moderate
73.9Moderate
83.9Moderate
93.9Moderate
103.8Moderate
113.8Moderate
123.7Moderate
133.7Moderate
143.6Moderate
153.6Moderate
163.5Moderate
173.5Moderate
183.5Moderate
193.4Moderate
203.4Moderate
213.3Moderate
223.3Moderate
233.2Moderate
243.2Moderate
253.1Moderate
263.1Moderate
273.0Moderate
283.0Moderate
292.9Moderate
302.9Moderate
Planning a trip in September

Is September a good time to visit Wil?

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
2.1
Beach & pool
4th-best month of the year

September is a reasonable time to visit Wil for sightseeing.

What to pack for Wil in September

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

In September, Wil sees daytime highs around 18°C and nights near 12°C. Worth packing: rain gear. About 12 days see rain.

rain gear

UV index in Wil 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 Wil peaks around July 15 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 22 at about 1 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJul 15UV 8Dec 22UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar4Moderate
Apr5Moderate
May7High
Jun7Very high
Jul8Very high
Aug7High
Sep4Moderate
Oct3Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Wil?

Wil sits at 47.5°N, 9.0°E, 569 m above sea level, in Switzerland. The nearest listed city is Frauenfeld, 15 km away.

HerisauSeen (Kreis 3)Oberwinterthur (Kreis 2)KreuzlingenWetzikonKonstanz

Topography around Wil

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

Within 3 km, the terrain around Wil has only modest variations in elevation — a maximum elevation change of 232 m around an average of 584 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 887 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,278 m.

The land around Wil is covered by grassland (38%) and trees (35%) within 3 km, trees (42%) and grassland (40%) within 16 km, and trees (43%) and grassland (34%) within 80 km.

3 km
232 m
16 km
887 m
80 km
3,278 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Frauenfeld 15 km · Gossau 17 km · Herisau 19 km · Seen (Kreis 3) 21 km · Oberwinterthur (Kreis 2) 22 km · Kreuzlingen 23 km · Wetzikon 24 km · Konstanz 24 km

Switzerland travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / J
230 V · 50 Hz
Prices
≈ 112% of US
price level, 2025
GDP per capita
$114,769
2025
Happiness
7.0 / 10
World Happiness, 2025
Safe drinking water
97%
of population, 2024
Homicide rate
0.6
per 100k, 2023
Road deaths
2.2
per 100k/yr, 2019
Income group
High
World Bank
English
High
EF EPI 564
Religion
Roman Catholic 34%none 29%Protestant 23%other Christian 6%

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 Wil (47.4615°, 9.0455°, elevation 569 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).