Dubuque weather in September

In September, Dubuque sees average daytime highs of 73°F and overnight lows near 55°F, with 3.6 in of rain across 8.3 wet days and about 12.3 hours of daylight. It is the 4th-warmest and 6th-wettest month of the year here.

Highs ease over the month, from about 78°F in the first days to 68°F by the end. The sky is clear or mostly clear about 44% of the time in September, and the air most often feels dry.

Daylight stretches from about 13 hours at the start of September to 11 h 36 min by month's end. Set against the rest of the year, September is Dubuque's 1st-clearest and 9th-windiest month. For the whole year in context, see Dubuque's year-round climate.

Daytime high
73°
4th warmest
Overnight low
55°
9th coldest
Rainfall
3.6 in
8.3 wet days
Daylight
12 h 18 min
5:48 AM – 6:05 PM
Cloud cover
49%
1st clearest
Wind
7 mph
9th windiest
Solar energy
4.41 kWh/m²
Travel score
7.1
out of 10

Dubuque is city in and county seat of Dubuque, Iowa, United States.

Density
719/km²
people per km²
Founded
1788

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 78°F in the first days to 68°F by the end.

A typical September day in Dubuque reaches about 73°F in the afternoon and slips back to 55°F overnight — a 18°F spread between the day's warmth and the night's chill. On most days the high lands between 62°F and 83°F. Set against its neighbours, September runs about 7°F cooler than August and about 13°F warmer than October.

40°60°80°151015202530
Avg high (°F)Avg low (°F)
17860
27860
37859
47759
57759
67758
77658
87658
97657
107557
117556
127456
137456
147455
157355
167354
177254
187254
197253
207153
217152
227052
237051
246951
256951
266950
276850
286849
296749
306749

How September really feels in Dubuque

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.

Dubuque weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°F)Rainfall (inches)Wet daysSnow daysDaylight (hours)Travel score
Jan28° / 13°1.57.469.20.0
Feb32° / 17°1.76.6510.30.0
Mar45° / 29°2.593.411.61.1
Apr58° / 40°4.211.71.113.14.0
May69° / 51°4.412.7014.45.9
Jun78° / 61°4.712015.16.4
Jul82° / 65°3.89.9014.86.5
Aug80° / 63°3.89.7013.76.8
Sep73° / 55°3.68.3012.37.1
Oct60° / 42°2.78.60.410.84.9
Nov45° / 31°2.37.529.61.1
Dec33° / 20°1.97.75.48.90.0

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 44% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 12% of September, with mostly cloudy or overcast conditions the remaining 44%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
16238
26238
36238
46238
56238
66139
76139
86040
96040
105941
115842
125743
135644
145545
155446
165446
175347
185347
195347
205347
215347
225347
235347
245347
255347
265347
275347
285446
295446
305446

Chance of precipitation in September

Any precipitation

Dubuque gets around 3.6 in of rain over 8.3 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 28% and peaks near 30% on the wettest days.

0%10%20%30%40%151015202530
Rain chance (%)
127
226
326
426
526
626
726
826
927
1027
1128
1228
1329
1429
1530
1630
1730
1830
1930
2030
2130
2230
2330
2430
2530
2630
2729
2829
2929
3028

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 54% of days. Sticky, muggy-or-worse air turns up on roughly 11% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1272522187
2292522177
3312522166
4342521156
5362521145
6382420135
7402420124
8412420114
9432319113
10452319113
11462318102
12482317102
13492217102
14512216101
15522215101
1654221491
1755211491
1856211391
1960201280
2062191180
2163191170
2265181070
236817960
246916960
257215850
267314850
277514740
287613740
297812730
308011630

Wind in September

Winds average 7 mph in September.

Across September, daily wind ranges from about 7 mph on the calmest days to 8 mph at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (mph)Feels
17calm
27calm
37calm
47calm
57calm
67calm
77calm
87calm
97calm
107calm
117calm
127calm
137calm
147calm
157calm
167calm
177calm
187light breeze
197light breeze
208light breeze
218light breeze
228light breeze
238light breeze
248light breeze
258light breeze
268light breeze
278light breeze
288light breeze
298light breeze
308light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 13 hours 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 84 minutes over September. Sunrise moves from 5:32 AM to 6:04 AM, and sunset from 6:33 PM to 5:40 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
113.05:326:33
213.05:336:31
312.95:346:29
412.95:356:27
512.85:366:26
612.85:386:24
712.75:396:22
812.75:406:20
912.65:416:18
1012.65:426:17
1112.55:436:15
1212.55:446:13
1312.45:456:11
1412.45:466:09
1512.35:476:07
1612.35:486:05
1712.25:506:04
1812.25:516:02
1912.15:526:00
2012.15:535:58
2112.05:545:56
2212.05:555:54
2311.95:565:53
2411.95:575:51
2511.85:585:49
2611.86:005:47
2711.76:015:45
2811.76:025:43
2911.66:035:42
3011.66:045:40

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.41 kWh/m².

For context, solar energy here swings from a low near 1.62 kWh/m² to a high of 6.3 kWh/m² in June across the year — September's 4.41 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
34.9Bright
44.9Bright
54.9Bright
64.8Bright
74.8Bright
84.7Bright
94.7Bright
104.6Bright
114.6Bright
124.5Bright
134.5Bright
144.4Bright
154.4Bright
164.3Bright
174.3Bright
184.2Bright
194.2Bright
204.2Bright
214.1Bright
224.1Bright
234.0Bright
244.0Moderate
254.0Moderate
263.9Moderate
273.9Moderate
283.8Moderate
293.8Moderate
303.8Moderate
Planning a trip in September

Is September a good time to visit Dubuque?

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

7.1
Sightseeing
1st-best month of the year
5.2
Beach & pool
4th-best month of the year

September is one of the better times to visit Dubuque for general sightseeing.

What to pack for Dubuque in September

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

In September, Dubuque sees daytime highs around 73°F and nights near 55°F. Worth packing: light clothes and rain gear. About 8 days see rain.

light clothesrain gear

UV index in Dubuque in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Dubuque peaks around June 18 at about 9 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 2 (low).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighVery highHighModerateLowJun 18UV 9Jan 1UV 2
UV index (midday)Level
Jan2Low
Feb3Moderate
Mar4Moderate
Apr6High
May7Very high
Jun9Very high
Jul8Very high
Aug8Very high
Sep6High
Oct3Moderate
Nov2Moderate
Dec2Low

Air quality in Dubuque in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Dubuque is worst in July — around 16 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (October, 7 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodModerateGoodJul 1915 µg/m³Oct 227 µg/m³
PM2.5 (µg/m³)Level
Jan11Good
Feb13Moderate
Mar13Moderate
Apr11Good
May12Moderate
Jun13Moderate
Jul16Moderate
Aug14Moderate
Sep11Good
Oct7Good
Nov8Good
Dec9Good
Location & terrain

Where is Dubuque?

Dubuque sits at 42.5°N, 90.7°W, 620 ft above sea level, in United States. The nearest listed city is Clinton, 52 mi away.

Topography around Dubuque

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

Within 2 miles, the terrain around Dubuque has only modest variations in elevation — a maximum elevation change of 328 ft around an average of 715 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 633 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 896 ft.

The land around Dubuque is covered by artificial surfaces (36%) and trees (34%) within 2 miles, cropland (35%), trees (34%) and grassland (20%) within 10 miles, and cropland (57%) and trees (26%) within 50 miles.

2 miles
328 ft
10 miles
633 ft
50 miles
896 ft
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Clinton 52 mi · Freeport 55 mi · Marion 58 mi · Cedar Rapids 60 mi · Davenport 68 mi · Bettendorf 68 mi · Fitchburg 68 mi · Rock Island 68 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 Dubuque (42.5006°, -90.6646°, elevation 620 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. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).