Willmar weather in September

In September, Willmar sees average daytime highs of 71°F and overnight lows near 51°F, with 3.3 in of rain across 8.8 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 5th-wettest month of the year here.

Highs ease over the month, from about 76°F in the first days to 66°F by the end. The sky is clear or mostly clear about 43% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 h 06 min at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Willmar's 2nd-clearest and 9th-windiest month. For the whole year in context, see Willmar's year-round climate.

Daytime high
71°
4th warmest
Overnight low
51°
9th coldest
Rainfall
3.3 in
8.8 wet days
Daylight
12 h 18 min
6:05 AM – 6:24 PM
Cloud cover
49%
2nd clearest
Wind
9 mph
9th windiest
Solar energy
4.28 kWh/m²
Travel score
6.9
out of 10

Willmar is city in Minnesota, USA.

Density
475/km²
people per km²
Founded
1871

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 76°F in the first days to 66°F by the end.

A typical September day in Willmar reaches about 71°F in the afternoon and slips back to 51°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 59°F and 84°F. Set against its neighbours, September runs about 7°F cooler than August and about 14°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17757
27657
37657
47656
57656
67555
77555
87455
97454
107454
117353
127353
137353
147252
157252
167151
177151
187050
197050
206949
216949
226949
236848
246848
256747
266747
276746
286646
296646
306545

How September really feels in Willmar

Once humidity and wind are folded in, September averages 0 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.

Days feeling ≥ 90°F
0
heat index over the day's high
Days feeling ≤ 32°F
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.

Willmar 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 (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan21° / 0.95.25.490.0
Feb26° / 10°0.954.410.10.0
Mar39° / 22°1.87.24.111.60.3
Apr55° / 35°3.19.92.513.23.4
May68° / 48°4.112.10.114.65.9
Jun77° / 59°5.412.6015.46.3
Jul81° / 63°3.79.7015.16.7
Aug79° / 60°3.89.3013.97.0
Sep71° / 51°3.38.8012.36.9
Oct57° / 39°2.58.10.710.74.3
Nov40° / 25°1.65.73.59.30.5
Dec26° / 12°1.15.55.58.60.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% 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 41%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16535
26535
36535
46535
56535
66337
76337
86337
96139
106139
116139
125941
135941
145743
155743
165545
175545
185545
195545
205545
215545
225644
235644
245644
255644
265545
275644
285644
295545
305545

Chance of precipitation in September

Any precipitation

Willmar gets around 3.3 in of rain over 8.8 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 29% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
129
229
329
429
529
629
729
829
929
1029
1129
1229
1329
1430
1530
1630
1730
1830
1930
2030
2130
2230
2330
2430
2529
2629
2729
2829
2929
3029

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 65% of days. Sticky, muggy-or-worse air turns up on roughly 6% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1392222162
2412221151
3442120131
4462120121
5482020111
6501920101
753181991
855171981
955171981
1058161871
1160161860
1262151760
1363151750
1465151640
1566151540
1667151530
1768151430
1869151330
1971151220
2072151120
2174141020
227514920
237813810
247913710
258112610
268311510
278311510
288510410
29879400
30898300

Wind in September

Winds average 9 mph in September.

Across September, daily wind ranges from about 9 mph on the calmest days to 10 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
19light breeze
29light breeze
39light breeze
49light breeze
59light breeze
69light breeze
79light breeze
89light breeze
99light breeze
109light breeze
119light breeze
129light breeze
139light breeze
149light breeze
159light breeze
169light breeze
179light breeze
189light breeze
1910light breeze
2010light breeze
2110light breeze
2210light breeze
2310light breeze
2410light breeze
2510light breeze
2610light breeze
2710light breeze
2810light breeze
2910light breeze
3010light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 h 06 min at the start of September to 11 h 36 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 90 minutes over September. Sunrise moves from 5:47 AM to 6:23 AM, and sunset from 6:53 PM to 5:56 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.15:476:53
213.15:486:51
313.05:496:49
413.05:506:47
512.95:526:45
612.85:536:44
712.85:546:42
812.75:556:40
912.75:576:38
1012.65:586:36
1112.65:596:34
1212.56:006:32
1312.56:016:30
1412.46:036:28
1512.46:046:26
1612.36:056:24
1712.36:066:22
1812.26:086:20
1912.16:096:18
2012.16:106:16
2112.06:116:14
2212.06:136:12
2311.96:146:10
2411.96:156:08
2511.86:166:06
2611.86:186:04
2711.76:196:02
2811.76:206:00
2911.66:225:58
3011.66:235:56

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.28 kWh/m².

For context, solar energy here swings from a low near 1.53 kWh/m² to a high of 6.44 kWh/m² in July across the year — September's 4.28 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
34.9Bright
44.9Bright
54.8Bright
64.8Bright
74.7Bright
84.7Bright
94.6Bright
104.5Bright
114.5Bright
124.4Bright
134.3Bright
144.3Bright
154.2Bright
164.2Bright
174.1Bright
184.1Bright
194.0Bright
204.0Moderate
214.0Moderate
223.9Moderate
233.9Moderate
243.8Moderate
253.8Moderate
263.8Moderate
273.7Moderate
283.7Moderate
293.6Moderate
303.6Moderate
Planning a trip in September

Hazard calendar for Willmar

In seasonPeak

In September, Willmar sits inside its rainy season season. The full year is below, with each hazard's peak months called out.

Willmar's rainy season runs April–October, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Willmar?

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

6.9
Sightseeing
2nd-best month of the year
4.7
Beach & pool
4th-best month of the year

September is a reasonable time to visit Willmar for sightseeing.

What to pack for Willmar in September

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

In September, Willmar sees daytime highs around 71°F and nights near 51°F. Worth packing: rain gear. About 9 days see rain.

rain gear

UV index in Willmar in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Willmar peaks around June 20 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 11 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 highHighModerateLowJun 20UV 8Jan 11UV 1
UV index (midday)Level
Jan1Low
Feb2Low
Mar3Moderate
Apr5Moderate
May6High
Jun9Very high
Jul8Very high
Aug7High
Sep5High
Oct4Moderate
Nov2Low
Dec1Low
Location & terrain

Where is Willmar?

Willmar sits at 45.1°N, 95.0°W, 1,142 ft above sea level, in United States. The nearest listed city is Saint Cloud, 52 mi away.

Topography around Willmar

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Willmar.

Within 2 miles, the terrain around Willmar has only modest variations in elevation — a maximum elevation change of 105 ft around an average of 1,132 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 230 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 692 ft.

The land around Willmar is covered by trees (23%), grassland (22%) and artificial surfaces (22%) within 2 miles, cropland (62%) within 10 miles, and cropland (74%) within 50 miles.

2 miles
105 ft
10 miles
230 ft
50 miles
692 ft
treesgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Saint Cloud 52 mi · Sartell 53 mi · Buffalo 57 mi · Saint Michael 67 mi · Otsego 71 mi · Elk River 73 mi · Chaska 74 mi · Chanhassen 76 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Willmar (45.1219°, -95.0433°, elevation 1,142 ft), 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).